CY & CX 400THM: differences & similarities

[Chevy454]

Using a 1969 "Hydra-matic Production Parts" list, I charted the differences and similarities between the "CY" & "CX" automatic transmissions, as well the difference between the "CY" & "CX" and the standard 400 automatic transmission.

http://www.yenko.net/attachments/400THM.jpg

[Mr70]

That's Real Nice work Rob. http://www.yenko.net/ubbthreads/images/graemlins/biggthumpup.gif

[SS427]

Very nice Rob and very helpful!

[CamarosRus]

Rob, To help the inept, like myself which vechicles used a CY or CW and what is diff between them (CW/CY). My ORIGINAL 70 Z-28 (bought NEW) with column shifted T-400......may I assume this had either of the two???
Thanks, Chuck

[Mr70]

For the year 1970:
*TH400 CY Trans. was coded for the LS6 Chevelle,& Corvette LS5.
Higher-shift point and stronger bands & springs.I believe a thicker shaft as well?
*TH400 CW Trans. was coded for the L78 Chevelle-Nova-Camaro,& LT-1 Camaro-Nova.
*TH400 CR & CS Trans. was coded for the LS5 Chevelle-Monte Carlo,& Corvette w/Transitorizied Ignition.
*TH400 CF Trans. was coded for the L34 Chevelle-Camaro-Nova.
*TH400 CK Trans. was coded for the 300HP 350cid Corvette.

[YENKO DEUCE REGISTRY]

Chuck, the comparison is between the CX vs. the CY, not the CW version. The CW was used in the L78's, LT1's etc...

[Chevy454]

Ray Morrison sent me some more 400-THM info. It was an application chart for 1969, so I went ahead and ran it through Excel so it's easier to digest...

http://www.yenko.net/attachments/118862-400RAY1.jpg

[Chevy454]

Here are some detailed pictures from a 1968 CY THM400 trans, courtesy of Tommy K and the Super Car Workshop...

http://www.yenko.net/attachments/132661-12.jpg

[Chevy454]

VIN...

http://www.yenko.net/attachments/132662-13.jpg

[Chevy454]

Writing...

http://www.yenko.net/attachments/132663-14.jpg

[Chevy454]

Stamp...

http://www.yenko.net/attachments/132664-15.jpg

[Chevy454]

Here are some detailed pictures from a 1969 CX THM400 trans, courtesy of the Super Car Workshop...

http://www.yenko.net/attachments/132923-CX1.jpg

[Chevy454]

6-lug convertor...

http://www.yenko.net/attachments/132924-CX3.jpg

[Chevy454]

Entire assembly...

http://www.yenko.net/attachments/132925-CX2.jpg

[Mr70]

What Car is this trans going into,if I may ask?

[Kim_Howie]

Tommy K's blue Harrell nova http://www.yenko.net/ubbthreads/images/graemlins/worship.gif http://www.yenko.net/ubbthreads/images/graemlins/worship.gif http://www.yenko.net/ubbthreads/images/graemlins/beers.gif

[bkhpah]

The 69 CX was from the 69 Dana Nova, the 68 is Tommy K's 68 Gibb/Harrell #44 Nova...BKH

[Mr70]

That Yellow CX tag looks very nice.
Has it been restored,unrestored,or is it a new replacement that are available today?

[bkhpah]

100% original tag. Just cleaned...BKH

[@wot]

Where is the VIN located on this transmission.

Thanks

[@wot]

Forgot to ask if anyone has a source for speedometer drive gears for TH 400?


Thanks

[Mr70]

I have compiled a list of speedometer gears.
What specifically are you wanting to know?
Color-Ratio-Part#?

Look for a CON VIN possibly stamped around the bell housing as well as into a recessed machined pad located were the Trans. oil pan meetes the trans. valve body.
It's behind the shift linkage rubber boot.
It is parallel to the head pipe,so you will have to look behind the head pipe,and wipe the pad clean to notice.

[@wot]

Mr70,

Thanks for the reply. I need the stock replacement gear for a TH400 with 3:55gears. Someone had changed it when they changed the tire size.

[Mr70]

Gear Part #9780470,Gray in color with 44 teeth used on 3:55 ratio with F70X14,G70X14 tires on 1968 Chevelle-Elco-Camaro.

[WILMASBOYL78]

What are the shift points on the L78 th400 trans setup under full throttle application? If you just start out in "drive" and floor it, at what rpm will it shift fron 1-2 and then 2-3?? Trying to dial in the trans in one of my cars with th400 and 4.10 rear.

wilma

[WILMASBOYL78]

Any th400 experts have some feedback???

thanks, wilma

[Mr70]

I want to say my L-78 TH400 Chevelle fitted w/4:10/F70X14 shifts from:
1-2 @ 10-15MPH.
2-3 @ 18-25MPH.
I can double check the RPM for you this week.. http://www.yenko.net/ubbthreads/images/graemlins/burnout.gif

I see a 70 Nova L-78 w/3:55/E70X14 shifts from:
1-2 @ 7-12 MPH.
2-3 @ 18-35 MPH.

[Chevy454]

Wilma...look at the chart at the beginning of the thread, and grab the numbers for the governor parts...see if ya can't still get those parts (maybe even from GM)...if you can, problem solved... http://www.yenko.net/ubbthreads/images/graemlins/beers.gif

[Mr70]

The 1970 L-78 CW TH400 trans. used Governor #8626866.

[rangelec]

I just found a CW turbo 400 trans with a 6 bolt converter-supposed to be out of a 70 Z28. How much are these going for? The guy wants a grand for it-is that out of line???

[Mr70]

I'd buy it for that.
What's the VIN# stamped into the machined pad on the drivers side,just above the shift linkage behind the rubber boot?
Can you read the Pass. side aluminum tag as well?

[Mr70]

rangelec
I wanted to reply to your question in the 6-lug convertor thread about this TH400,so I thought this topic was better.
The 1970 CW is a seldom seen scarce Transmission.
1970 CW TH400 was designed for specific Solid lifter BB & SB Applications.
They were:
*Chevelle-Nova-Camaro L-78 402/375HP.
*Camaro Z/28-Nova LT-1 350/360HP Yenko Deuce.
Not knowing it's overall condition,I'd say it's worth the 1K regardless.

[Hotrodpaul]

I have the CW coded trans in my 70 Z28. What is different about this transmission over a CX or CY tranny and any other unique features. It also has the 6-bolt converter.

Paul

[oramac68]

Hello everyone, I'm confused, which one would go in a 69 Camaro or Chevelle L-78, a CW, CY , CX or CC? , Thanks

[Mr70]

1969 Camaro & Chevelle used the CX TH400,as well as other solid lifter applications.
1970 was new for the CW suffix TH400,in the L-78 & LT-1 Camaro-Nova-Chevelle.

[fpcopo]

To Wilmasboy:

My research has said that the design upshift speed at WOT of the 69 CY trans was 5900 to 6100. The high speed governor will help you up your shift points but also affecting shift timing are line pressure and accumulator springs and pistons. Also the trans was designed for hard use as all wavy shift plates from clutch packs were removed for harder as well as quicker shifts. Some other mods were the forward clutch drums have 2 oil bleed check balls instead of 1, this allows oil to dump faster to speed shift timing. The 6 lug convertors were first used in trucks so you can find trucks with the same convertor shell but everything inside is vastly different. Frank

[Michael4yah]

Would you happen to have the list for the 68's

[Chevy454]

I believe it's gonna be the same...except the converter is different, which according to Ray Morrison flashes in the ~1800 rpm range...

[JohnZ]

Here's the tag on a "CY" in a neighbor's all-original '71 LS-6 Corvette:

http://img.villagephotos.com/p/2002-2/13522/TH400Plate.jpg

http://www.yenko.net/ubbthreads/images/graemlins/beers.gif

[nuch_ss396]

[ QUOTE ]

The 6 lug convertors were first used in trucks so you can find trucks with the same convertor shell but everything inside is vastly different. Frank

[/ QUOTE ]

Frank,

I recently found a 69 CX THM400 out of an L/78 Nova. I now
need the correct 6-lug converter. I see them on eBay from
time to time, but you comment about the truck converter
being vastly different concerns me. How does one know if
you have a true SHP 6-lug converter? Or, are they still
available from GM with the proper internals for an L/78?
http://www.yenko.net/ubbthreads/images/graemlins/dunno.gif

BTW, were the SHP converters stamped or coded in any way?
Steve

[Chevy454]

From some conversations I had with S/SS racer Russ Abrams, who is a Hydra-Matic employee...

[ QUOTE ]
If you have a real CX/CY converter, then look at the OD of the rear section of the converter. It should have letters such as "C" or "D". That indicates a "loose" pump. The trucks have no letters or "A". Six lug converters were used for high rpm or high torque applications. There was a special VB and governor for the CX/CY models, that information disappeared, when GM went to computers to store info. The 400 was out of production ,so the info was canned. Russ

[/ QUOTE ]

[nuch_ss396]

[ QUOTE ]
From some conversations I had with S/SS racer Russ Abrams, who is a Hydra-Matic employee...

[ QUOTE ]
If you have a real CX/CY converter, then look at the OD of the rear section of the converter. It should have letters such as "C" or "D". That indicates a "loose" pump. The trucks have no letters or "A". Six lug converters were used for high rpm or high torque applications. There was a special VB and governor for the CX/CY models, that information disappeared, when GM went to computers to store info. The 400 was out of production ,so the info was canned. Russ

[/ QUOTE ]

[/ QUOTE ]

Rob,

Any chance you or the gentleman you quoted have an image
of the "letters"? Were they ink stamped or punched in.

Does anyone here have an original SHP 6-lug converter that
they can check for these "letters"? I'd like to know more
about this since this is the first I'vw heard of it.

These are the kinds of details you just can't get anywhere
else. http://www.yenko.net/ubbthreads/images/graemlins/worship.gif http://www.yenko.net/ubbthreads/images/graemlins/biggthumpup.gif

Steve

[KevinCav]

I have one of those 6-lug converters for a CY trans that I have. The letter "c" is stamped on the converter in a very small font and is located approx. 4.5 in. from the centerline of the shaft hole. I'll try to post a picture of this in the next week or so.

[Chevy454]

DOH! Sorry nuch...just now saw the above post...unfortunately, I don't have an original CX converter...like a MORON I let one go with an L78 Chevelle I sold a few years back...sounds like I need to run over the Ray's house and get a picture of the original converter out of his '68 COPO...

[nuch_ss396]

Great !

I'll be waiting to see the picture(s) of the stamping.

Steve

[KevinCav]

Sorry it took so long, but here are some pictures of the stamping on the 6-lug converter out of my orignal CY transmission.

[WILMASBOYL78]

Attachment won't open for me..??

wilma http://www.yenko.net/ubbthreads/images/graemlins/confused.gif

[KevinCav]

HELP! I want to post these pic's of the stamping on the converter, but I'm having trouble. Can someone please tell me the correct way to post them? Thanks.

[nuch_ss396]

Kevin,

I sent you a PM.

Steve

[nuch_ss396]

Here are some pictures of Kevin's CY converter. http://www.yenko.net/ubbthreads/images/graemlins/worship.gif

Steve

http://webzoom.freewebs.com/nuch_ss396/original%2DCY%2Dconverter2.JPG

http://webzoom.freewebs.com/nuch_ss396/original%2DCY%2Dconverter1.JPG

[nuch_ss396]

This thread is fantastic ! http://www.yenko.net/ubbthreads/images/graemlins/worship.gif

Now I know exactly what converter I need to look for. Now,
all I need to do is find that needle in the haystack.....

Well, I found the CX THM400, finding one of the correct
torque converters can't be any harder, can it? http://www.yenko.net/ubbthreads/images/graemlins/dunno.gif
Come-on everybody! Tell me it gets easier! http://www.yenko.net/ubbthreads/images/graemlins/headbang.gif

Steve

[Paul D]

I understand that the CW Turbo 400 in a '70 Z28 has a 2400 rpm converter. Is the CW similar to the CX transmission?

[Michael4yah]

Anyone know the #s and prefix for a turbo400 in a 68 Camaro 396/350hp??

[JHS]

Here is a pic of the CW tag on my 1970 Nova L78. Where on the case is the VIN? I never looked for it and the tranny is back in the car. Had to post pic as an attachment.

[Hotrodpaul]

I also have a CW trans in my 70 Z-28. I found the VIN stamped on the drivers side pan rail area recessed slightly. Did not see it until the exhaust pipe was removed. The stamp was at an angle when struck.

http://i3.photobucket.com/albums/y86/Hotrodpaul86/DSCN5162.jpg

reads 0L510574.

Paul

[YENKO DEUCE REGISTRY]

The vin will be on the pan rail or the flange of the bellhousing.

[@wot]

1970 cw vin

[Kim_Howie]

Are you sure that's a camaro trans Looks like a nova trans because of the W in the vin???

[@wot]

Its a Nova trans. Not sure if Camaros are in the same position.

[Kim_Howie]

Sorry, I thought you were talking about your camaro trans. http://www.yenko.net/ubbthreads/images/graemlins/biggthumpup.gif http://www.yenko.net/ubbthreads/images/graemlins/flag.gif

[@wot]

I mistakenly thought I was responding to the post by JHS, concerning vin location. I'm not awake yet!

[JHS]

[ QUOTE ]
Sorry, I thought you were talking about your camaro trans. http://www.yenko.net/ubbthreads/images/graemlins/biggthumpup.gif http://www.yenko.net/ubbthreads/images/graemlins/flag.gif

[/ QUOTE ]

I am sure I confused the whole gang by interjecting my Nova CW trans. question, sorry!! I had someone ask me for a pic of my CW tag at one point so thought I would post it here for comparison purposes.

[Xplantdad]

It's all good Joe! http://www.yenko.net/ubbthreads/images/graemlins/beers.gif

[Bergerz28]

Need help for my L78 Chevelle SS,need a cx transmission,any help or info would be great,thanks Thomas

[nuch_ss396]

Good luck on that one Thomas. It only took me 7 years to
find mine. http://www.yenko.net/ubbthreads/images/graemlins/frown.gif Hope you're luckier than I was.

Steve

[Stan Kryla]

Anyone have this same info for 1972?

[COPO 70 RS/Z28]

What is the reason for the different color tags? I have seen the same designation tags with different colors??

Thanks

http://www.yenko.net/ubbthreads/images/graemlins/dunno.gif

[nuch_ss396]

Carl,

I thought the colors were year specific. Fo rinstance, 1969
THM400 tags were yellow. I believe 1970 tags were a light
blue/green color......

Nuch

[COPO 70 RS/Z28]

Are some black??? or do they just look dark?

Thanks http://www.yenko.net/ubbthreads/images/graemlins/worship.gif

[WILMASBOYL78]

The tag on the 70 CW coded trans was black....other applications may have used a different color....I have only seen the L78 tags...


wilma

[nuch_ss396]

[ QUOTE ]
Are some black??? or do they just look dark?

Thanks http://www.yenko.net/ubbthreads/images/graemlins/worship.gif

[/ QUOTE ]

I'll check my database and get back to you......

Nuch

[nuch_ss396]

Try this for size:

( you need an ebay login for the search engine to work http://www.yenko.net/ubbthreads/images/graemlins/grin.gif)

ebay search for THM tags (http://search-completed.ebay.com/search/search.dll?sofocus=bs&sbrftog=1&dfsp=1&fcl=3&catre f=C6&frpp=50&from=R7&mppfqy=%28turbo+400%2C+THM400 %2C+TH400%29TORQUE+CONVERTER&satitle=transmission+ tags&sacat=6000%26catref%3DC6&fmmk=&fmmd=&fylo=&fy hi=&mppfqy=%28turbo+400%2C+THM400%2C+TH400%29TORQU E+CONVERTER&sargn=-1%26saslc%3D2&sadis=200&fpos=28791&sabfmts=1&saobf mts=insif&fis=2&ftrt=1&ftrv=1&saprclo=&saprchi=&sa dis1=100&fpos1=28791&lsot1=&fsop=1%26fsoo%3D2&fgtp =&sadis2=100&fpos2=28791&lsot2=)

Nuch

[COPO 70 RS/Z28]

WOW,

Most of those are yellow, listed for lots of diff years!!!

Man ??? http://www.yenko.net/ubbthreads/images/graemlins/confused.gif http://www.yenko.net/ubbthreads/images/graemlins/confused.gif http://www.yenko.net/ubbthreads/images/graemlins/confused.gif http://www.yenko.net/ubbthreads/images/graemlins/confused.gif http://www.yenko.net/ubbthreads/images/graemlins/confused.gif

[jeff-san]

I am having an issue with my CX tranny...under partial to 1/2 throttle the Nova lights up the tires and shifts firmly into the next gear... but under heavy to full throttle around 5-6k I hear a slight squeal, then the tranny slips before it shifts into 2nd. I know it has and adjustable vacuum mod as I took a few pictures for Tom W...will an adj of this screw in or out fix this? any help out there? http://www.yenko.net/ubbthreads/images/graemlins/dunno.gif

[Mr70]

I don't think adjusting the Vac. Mod. will cure it,as it sounds more serious.
I had a similar situation and it was a clutch pack sticking.
It could also be a compression band that won't release.
1st check your fluid & filter for color & debris.

[mockingbird812]

Jeff - should it be more serious I have a friend who you could trust to fix your tranny. He is in my neighborhood, is a retired GM Proving Grounds Auto Tranny expert with beauceaup experience with 400s, and an excellent reputation. He has a complete shop on his property. Let me know. Good luck.

[jeff-san]

I may pull the tranny. when I bought it, I had all the fluids changed and a tune-up. the guy changed the tranny filter and althought the fluid was old he didnt notice any fragments from the clutch pack or metal in the pan. I may contact you about your tranny man. I have also heard good things about Mike's Trans in Lancaster, Ca. thanks for both of your imputs...I was trying to avoid pulling the tranny but I guess I cant get around it.

[Chevy454]

An easy check, and probably not the case (but learned by experience), make sure you have the correct pickup tube if it has a deep pan on it...doesn't sound like a modulator problem, sounds more like a hard part...but I'm no tranny guy by any means!

[jeff-san]

[ QUOTE ]
An easy check, and probably not the case (but learned by experience), make sure you have the correct pickup tube if it has a deep pan on it...doesn't sound like a modulator problem, sounds more like a hard part...but I'm no tranny guy by any means!

[/ QUOTE ]

this may be a good lead. I noticed the ccar didnt have it's original tranny pan...it looks deeper than stock and it's finned. maybe they didnt make the adjustment on the pan depth? if this is the case, could it cause some of the problems that I'm experiencing? My buddy that did the tune-up swears these tranny are bullet proof and it had to be something simple...especially since he saw no signs of metal or clutch schmegma in the pan or filter when he changed it. I'll try it. thanks, I hope it helps.

[Xplantdad]

If you have to pull it...bring it out this way. It'll give you a chance to hook up with Sam and me...heck, I'll spring for a barbeque at my place...

[jeff-san]

[ QUOTE ]
If you have to pull it...bring it out this way. It'll give you a chance to hook up with Sam and me...heck, I'll spring for a barbeque at my place...

[/ QUOTE ]

I went home at lunch and started thinking about trying to pull the motor and tranny myself. The motor is fine but I might as well do a little detailing while it's out. You may see me sooner than later...crank up the barbie!

[Chevy454]

[ QUOTE ]
this may be a good lead. I noticed the ccar didnt have it's original tranny pan...it looks deeper than stock and it's finned.

[/ QUOTE ]
It's indeed a long shot, but I learned the hard way...just wish I'd learned *before* driving all the way to Norwalk! http://www.yenko.net/ubbthreads/images/graemlins/tongue.gif

[mockingbird812]

Jeff- you may wish to call my friend and bounce your symptoms off of him over the phone. Rick @ 480.987-3756. Tell him his neighbor, Sam, sent you.

[WILMASBOYL78]

Jeff, I have spoken to Sam's buffy from GM...he knows his stuff. As for the deep pan...it won't impact performance provided the additional fluid it needs has been added. You may also want to check the governor to make sure there is no damage to the plastic gear. That tranny should shift at approx. 6100-6300 rpm under full throttle...both 1-2 and 2-3. The modualtor won't affect what you are describing. When I service my hi-perf trannys we use a flushing machine that my local tranny guy has...it really works to get any debris or metal filings out of the system. A reputable trany guy can pull that unit out with the motor in the car and solve your issues...it takes quite a bit to hurt these hi-perf TH400's.

good luck..wilma

[Xplantdad]

[ QUOTE ]
[ QUOTE ]
If you have to pull it...bring it out this way. It'll give you a chance to hook up with Sam and me...heck, I'll spring for a barbeque at my place...

[/ QUOTE ]

I went home at lunch and started thinking about trying to pull the motor and tranny myself. The motor is fine but I might as well do a little detailing while it's out. You may see me sooner than later...crank up the barbie!

[/ QUOTE ]

Either way, tranny or not...come on out. I'll get the 'cue going... http://www.yenko.net/ubbthreads/images/graemlins/grin.gif

[jeff-san]

I just pulled the tranny and semi-steamed off a mojority of the gunk. If anyone is interested, I can take a few pix.
- the 6 lug conv had the E7 on it
- a few darker big C's ink stamped
- I found 1 stamped letter J
- the outer case had a CX ink stamped on the passenger side 2 o clock position.

I couldnt find a VIN stamped anywhere. let me know if anyone needs to see pix of what I found. I can take them tonight.

[mockingbird812]

Take 'em then post 'em! http://www.yenko.net/ubbthreads/images/graemlins/tongue.gif http://www.yenko.net/ubbthreads/images/graemlins/laugh.gif http://www.yenko.net/ubbthreads/images/graemlins/biggthumpup.gif

[1969grb]

Jeff, I would like to see some pictures. I would like to compare to my other Nova's trans. Thanks Grady

[jeff-san]

I took the pix...Bruce is usually the guy that gets stuck with my inability to post pix. can anyone else help out if I email them?

[COPO 70 RS/Z28]

If I can help if you need it

Ill pm my email

http://www.yenko.net/ubbthreads/images/graemlins/beers.gif

[COPO 70 RS/Z28]

Jeffs Pix

http://i271.photobucket.com/albums/jj121/70COPORSZ28/L-78001.jpg

http://i271.photobucket.com/albums/jj121/70COPORSZ28/L-78002.jpg

http://i271.photobucket.com/albums/jj121/70COPORSZ28/L-78003.jpg

http://i271.photobucket.com/albums/jj121/70COPORSZ28/L-78007.jpg

http://i271.photobucket.com/albums/jj121/70COPORSZ28/L-78008.jpg

http://i271.photobucket.com/albums/jj121/70COPORSZ28/L-78009.jpg

http://i271.photobucket.com/albums/jj121/70COPORSZ28/L-78010.jpg

http://i271.photobucket.com/albums/jj121/70COPORSZ28/L-78011.jpg

http://i271.photobucket.com/albums/jj121/70COPORSZ28/L-78012.jpg

http://i271.photobucket.com/albums/jj121/70COPORSZ28/L-78013.jpg

http://i271.photobucket.com/albums/jj121/70COPORSZ28/L-78015.jpg

http://i271.photobucket.com/albums/jj121/70COPORSZ28/L-78016.jpg

http://i271.photobucket.com/albums/jj121/70COPORSZ28/L-78017.jpg

http://i271.photobucket.com/albums/jj121/70COPORSZ28/L-78019.jpg

http://www.yenko.net/ubbthreads/images/graemlins/beers.gif

[SS427]

Can someone post a close up picture of a 1970 CY trans paint stamp on the bellhousing? Thanks to Chad I have one photo but it is not clear enough to see what the writing is on either side of the CY. TIA
Rick

[jeff-san]

Carl,

thanks for posting the pix. sorry everything has a red hue, I didnt realize my red trailer would cause such a problem. I did find the vin numbers on the trans...they are so faint that it didnt show up on the pix but they do match.

thanks again for posting them

[ORIGLS6]

Great pix. Some of us 'anal types' love this kind of stuff!

http://www.yenko.net/ubbthreads/images/graemlins/beers.gif http://www.yenko.net/ubbthreads/images/graemlins/worship.gif

(Simple Green. http://www.yenko.net/ubbthreads/images/graemlins/biggthumpup.gif )

[1969grb]

Jeff, Thanks for the pictures.

Grady

[BARRY]

HY any one missing a C X trans cx 479 vin 19w49---5

[nuch_ss396]

[ QUOTE ]
HY any one missing a C X trans cx 479 vin 19w49---5

[/ QUOTE ]

How about --- Anyone want a CX trans http://www.yenko.net/ubbthreads/images/graemlins/naughty.gif

Nuch

[nuch_ss396]

http://i271.photobucket.com/albums/jj121/70COPORSZ28/L-78001.jpg


Thanks an amazing finish on a 40+ year old ID tag. What
are the particulars of that vehicle? In other words, was
the trans out of the car and stored inside for many years?
I found a CX trans that was removed in 1970 and stored in
a garage, but the ID tag still looks 40 years old.

What's the secret?

Nuch

[jeff-san]

[ QUOTE ]

http://i271.photobucket.com/albums/jj121/70COPORSZ28/L-78001.jpg




Thanks an amazing finish on a 40+ year old ID tag. What
are the particulars of that vehicle? In other words, was
the trans out of the car and stored inside for many years?
I found a CX trans that was removed in 1970 and stored in
a garage, but the ID tag still looks 40 years old.

What's the secret?

here is the link of the car in question.http://www.yenko.net/ubbthreads/showflat.php/Cat/0/Number/339830/an/0/page/0#Post339830

the only secret is that the car is a lo-mile Ca. car. I believe it spent a major portion of it's life stored indoors...at least from the 80's, probably longer. I hope this helps? I messed up the tag by putting steam on the case and accidentally hit the tag and peeled a little paint of the bottom...DOH!

Nuch

[/ QUOTE ]

[nuch_ss396]

After seeing the car in the thread you linked, http://www.yenko.net/ubbthreads/images/graemlins/eek.gif http://www.yenko.net/ubbthreads/images/graemlins/drool.gif <--- NICE CAR!

Your CX sequence is #426. Wonder who got #427 http://www.yenko.net/ubbthreads/images/graemlins/naughty.gif

Great find.

By the way Jeff, don't beat yourself up over the power washing of the tag incident. We all have one of those
boo-boo's to deal with somewhere........ http://www.yenko.net/ubbthreads/images/graemlins/blush.gif

Steve

[jeff-san]

I was told the 426 was a Julian date started Jan 1 of 68 so 426 was the end of Feb '69. I guess a bunch of guys possibly have CX tranny's with 427 build dates...very cool.

[nuch_ss396]

Jeff,

Here is my CX ID tag. Odd that yours is one below 427 and
mine is one below 396........ http://www.yenko.net/ubbthreads/images/graemlins/grin.gif

Steve

http://i244.photobucket.com/albums/gg15/nuch_ss396/MVC-005F.jpg

[sixt9rsx33]

[ QUOTE ]
For the year 1970:
*TH400 CY Trans. was coded for the LS6 Chevelle,& Corvette LS5.
Higher-shift point and stronger bands & springs.I believe a thicker shaft as well?
*TH400 CW Trans. was coded for the L78 Chevelle-Nova-Camaro,& LT-1 Camaro-Nova.
*TH400 CR & CS Trans. was coded for the LS5 Chevelle-Monte Carlo,& Corvette w/Transitorizied Ignition.
*TH400 CF Trans. was coded for the L34 Chevelle-Camaro-Nova.
*TH400 CK Trans. was coded for the 300HP 350cid Corvette.

[/ QUOTE ]

Would a 69 Chevelle SS L-78 be a CX code like the Camaro?

[Mr70]

Yes,as they too had a higher shift point.

[sixt9rsx33]

Thank you.

[Camaroresto]

What would this tranny be from...

tag CA 66 20597 with 286 stamped above that line.

[Mr70]

Any 1966 Impala-Belair-Biscayne-Caprice with a 396/325HP & TH400,assembled after October 13th,1965.

[mockingbird812]

Couple questions>

1. What trans codes are correct for '69 COPOs with automatics? Are they different for different models i.e. Camaro and Nova?

2. In '69 are the CX and CY codes used on all solid lifter motors (with automatic trans)?

3. Do all TH400s in '69 have partial VINS stamped on them?

Thanks!

[deuce-less]

69 L-78 nova CX trans

[deuce-less]

vin stamped on passenger side frt flange 4 times

[deuce-less]

69 CX yellow tag

[Zach Carter]

Can anyone tell me what the application for a TH400 with a 71-CA on the tag is?

Thanks

[Mr70]

For the Smallblock 400/255HP engine w/4bolt mains,denoted CLK when installed in any of the 1971 Impala series.

[Zach Carter]

Thanks Mr70!

[nova bob]

Looking for Thomas.. New to this site I have a 69 CX trans with the original converter. May be interested in selling it. Bob 708-687-5861 or [email protected]

[Zach Carter]

What trans ID tag would a 68 Gibb Nova have? CX or CY?

[ORIGLS6]

CX

[hiperf69]

Just a couple of questions that have come up.
Would anyone have any info as to why GM put "CY" trans in the Impala's and Chevelle's
And the "CX" trans in the Camaro's and Nova's?
According to the chart on the first page of this thread the diff. between "CY" and "CX" are the case, and the "CX" case is the same as the Std case,and the valvebody.
Am I correct in assuming the valvebody to be different because of the weight of the Impala,and Chevelle being more than the Camaro's and Nova's
One more thing, did the Corvette's use the "CY"s also?
Thanks,Joe.

[Mr70]

"Would anyone have any info as to why GM put "CY" trans in the Impala's and Chevelle's
And the "CX" trans in the Camaro's and Nova's?"

For 1969,is that a correct statement?..wasn't the CX early for all those Spcl.Hi-Perf equipped cars,later superceded by the CY for all those Spcl. Hi-Perf equipped cars?

I think there was a valvebody difference,but I'm not sure if that was it.
Thought the 427/430HP & 435Hp Corvettes did come with the CY,as of April 69.

[hiperf69]

Sorry, Yes this would be for '69.This what I am trying to find out,was there a change mid- prodution or were they both used all the way through from start of 1968.If there was a change,do you know what date this happened,Thanks.Joe.

[Smokey]

Wasn't the CY also the police car version too?

[Mr70]

Here's some docs..

http://i159.photobucket.com/albums/t142/peterspix_2007/Cytranspaper001.jpg

http://i838.photobucket.com/albums/zz310/bubblemug/Cytranspaper004.jpg

http://i159.photobucket.com/albums/t142/peterspix_2007/Cytranspaper003.jpg

http://i159.photobucket.com/albums/t142/peterspix_2007/Cytranspaper002.jpg

427 COPO Camaros & Novas show L-78 on their buildsheets as that's how they were assembled,and then had a 427cid. installed instead.I would think the CY trans was available in all 5 vehicle types w/Spcl. Hi-Perf 427cid. as of 4/69.

[hiperf69]

Thanks Rick ,this if I read this right,would mean cars built after this date April 14 1969 would have received the "CY" code trans. Books are good!!Joe

[Mr70]

Paper reports usually came out after the act was actually being done,so I would say even a lil before April 14,1969.
They may have been installing them much earlier then that,but because my books of these are incomplete,I don't have any earlier dates on paper to share then this one..

[deuce-less]

my 69 07D built L-78 nova came from the factory with a CX coded trans

[61 vert]

457 date would be around april 3rd which would put it slightly before the April 14th date mentioned as a possible cutoff date.I have a CY dated 478 ,2 weeks after the April 14 date. If we could come up with a bunch of CY and CX dates, a cuttoff could be narrowed in on.As far as comparing the trans cutoff date to when the cars switched, that would be tough.I suppose that they could have been intermingled until the CXs were all gone, or different plants could have run out of CXs at different times.Does this make sense?

[lbnaz]

Hello, not trying to piggy back on this just saw it I have a CY with the 6 bolt convertor out of a 73 Z/28 if there is any interest. Larry

[61 vert]

I would like to see s picture of the tag. If you don't want to post it here I will PM you my email.

[copo-2]

The redesigned T-400 was coded CY. These were used in the Gibb Nova's and were the first built 400's designed for competition. While not having any reference at this time to look at, I believe the documentation I have shows the CX transmission being introduced on October 24, 1968? I have heard of the CY being used in later versions, but don't know what is documented on this?

[lbnaz]

photo will not load

[61 vert]

Here you go
http://i118.photobucket.com/albums/o83/69tdega/camerapix178.jpg
http://i118.photobucket.com/albums/o83/69tdega/camerapix180.jpg
http://i118.photobucket.com/albums/o83/69tdega/camerapix179.jpg

[copo-2]

Took a couple of pictures of an original CY transmission with an untouched identification tag with Juno date of 534.
This is out of my personal Gibb Nova.

http://i211.photobucket.com/albums/bb303/DH427Nova/Turbo400001.jpg

http://i211.photobucket.com/albums/bb303/DH427Nova/Turbo400003-1.jpg

http://i211.photobucket.com/albums/bb303/DH427Nova/Turbo400004.jpg

http://i211.photobucket.com/albums/bb303/DH427Nova/Turbo400011.jpg

[lbnaz]

Hello, thank-you for posting the 73 photos. Larry

[copo-2]

I was off a day in the previous post as the date the CX tranny was added.

http://i211.photobucket.com/albums/bb303/DH427Nova/TransmissionCodes.jpg

[copo-2]

<span style="font-weight: bold"> </span> Concerning the CY transmissions that came in the Gibb Nova's, there was a special bulletin sent out to GM dealerships dated July 12, 1968. It reads:

NEW HEAVY DUTY TURBO HYDRA-MATIC TRANSMISSION

A new heavy duty or &quot;high speed&quot; version of the Turbo Hydra-Matic transmission will be available with the 425 HP 427 V-8 for Chevrolet models, the 396 375 HP Chevelle, Camaro, Chevy ll's and the 430 and 435 HP V-8 Corvette's. Previously pnly manual transmissions were available with these engines. The new transmissionincludes modifications to accept the greater engine torque, higher RPM, and generally more rigorous operation anticipated with these high output engines.

To accomodate engine speeds up to 7800 RPM, 1600 RPM higher than normal operationg speeds, a special torque converter assembly is used, with all pump and turbine blades welded rather crimped in place. The converter assembly is bolted to the engine flywheel at six points, double the number of the standard unit.

Because of the higher torque loads experienced during hard acceleration, premimum quality driven plate facings are used in the intermediate clutch, which is applied to accompolish the 1-2 upshift. Firmer upshifts are obtained through modifications to the accumulators in the itermediate 1-2 and direct 2-3 clutch apply circuits to reduce cushioning action. Gover calibrations are also revised to raise the maximum upshift point from 5100 to 6300 RPM.

All other design details, including converter ratio and gear ratios, are common with the Turbo Hydra-Matic use with regular high displacement engines.

[Donny]

I have a T400 1968 with a CD code. I thought it was from a BB Nova ?? If above is correct it is from a 350 2 BBL car????

[red67]

I have found quite a few 1968 (and possibly 1967) full size Chevrolets with this CD trans. The application I find these in is the 327 ci 275 hp. A friend has one in his shop right now that I looked at the other day. He assures me it is from a 327/275 car and he has had it for years. I believe this was before the TH350 was introduced to mass production in late 1968, early 1969. I also believe the CD code is the only common small block TH400, but there may be other small block codes.

[Slashnine]

hey thank , it was realy helpfull

[Donnie]

we've lost a lot of pictures from this topic. if we could upload our pics to the site like TeamChevelles that would'nt happen.

anyone know what color the CX ink stamp is on the outside of the case?

[juliosz]

This is very hard to see but it almost looks like green:
http://i617.photobucket.com/albums/tt254/lafeagle/tn_alanscamera033-1.jpg

[maddoghd]

what trans code would 70-ca 4684 with 317 above be? thx in advance

[Mr70]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">what trans code would 70-ca 4684 with 317 above be? thx in advance.</div></div>

That Turbo 400 trans. came out of a 265HP/400cid. equipped 1970 Impala-Biscayne-Bel Air-Caprice,including station wagons.
Trans was assembled November 13th of 1969.

[169indy]

Found a CX from 69 Chevelle
19K448923
Got it all cleaned up and rebuild to take the place of my &quot;CC&quot; 68 trans for a while and go behind a L78 in the future.
https://lh5.googleusercontent.com/-51-mgGLQyp0/UOO4ieIQndI/AAAAAAAAAGg/XQgAlMThc-E/s640/100_3647.JPG

[RogerD]

Nice find on the KAN VIN CX!

[SS427]

I second that!! I have never come across a CY or CX tans in the last 20 years and certainly never seen one in that nice a condition. Congrats on the find. Hopefully you did not have to forfeit an member of your body to get it.

[169indy]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: SS427</div><div class="ubbcode-body">I second that!! I have never come across a CY or CX tans in the last 20 years and certainly never seen one in that nice a condition. Congrats on the find. Hopefully you did not have to forfeit an member of your body to get it. </div></div>

In the PNW a ORIG owner sale on a 50kmile CX is $700 for the core. Stuck in a ORIG owners garage floor and advertised on a piece of cardboard at a swap meet, He knew it was special He was a retired service mechanic from Camas CHEVROLET in Vancouver WA. Not sure how I did but it does not matter I purchased it to USE &amp; ABUSE(enjoy) it (Joking)It sure likes to wind up. Silly me it is behind a L35 and a obvious missmatch. Found a CE 1967 cast L78 (From ID.) to be built at a latter date to power the 68 sometime soon.
This thread was very helpfull and I am thankful for the contributors.

Jim

[rke24]

Can anyone tell me what car a 70 cy 353 tranny code is for?

[Mr70]

It originally came in either a 1970 Chevelle/Elcamino 450HP/LS-6,or a 1970 Corvette 390HP/LS-5,both equipped with a TH400 obviously.

Any other numbers on the lower pat of the tag?

..it was assembled on Saturday Dec.19th,1969.

[rke24]

Thanks for the info!!
Its a short shaft, and the numbers on the bottom are 70-CY-1300

[Mr70]

1300 is the serial number of the transmission.

[lbnaz]

Looking for the application of a 65 dated T400 with CA on the tag. Thanks, Larry

[Mr70]

1965 Biscayne,Bel Air,Impala series with 396/325HP engine.

[lbnaz]

Hello, thank-you.

[lbnaz]

Does anyone have photos front and back of an original T400 6 lug convertor. Just came across one someone wrote GM 70 on seeing if it matches up. Thanks, Larry.

[WILMASBOYL78]

Here is what I have...this is from a 1970 Nova CW TH400...original 6 lug convertor.
Hope that helps...wilma


http://www.yenko.net/ubbthreads/pics/usergals/2016/03/full-1121-40739-tn_th400_l78_trans_007.jpg
http://www.yenko.net/ubbthreads/pics/usergals/2016/03/full-1121-40741-tn_th400_l78_trans_009.jpg

[lbnaz]

Hello, thank-you for the photos. Mine does not look like that so probably isn't GM. By the way your PM box is full tried answering that way. Larry

[lbnaz]

What would the Pontiac version of this trans be. I have a 68 PX would it be equivilant to the CX. Thanks, Larry. 520-349-2337

[Fast67VelleN2O]

Anyone know what a CY dated 1977 is from? Would this be a service unit?

[WILMASBOYL78]

Last reference I see in Colvin's book is 1974...perhaps you have a service unit??

[Mr70]

A service Trans with notate that it is.
Look around the bellhousing for stampings like CT 123456

[Big Block Bill]

Not to hijack this thread, but I have an N.O.S TH400 Transmission with out a tag on the right side dated 7-69 on the top of the case where it meets the extension housing. It has HOT00604 stamped on the left side above the pan rail where the shift cable would be. Anyone know what this stamp represents? Any help would be appreciated.

Bill

[Big Block Bill]

Picture of casting date.

Bill

[Mr70]

Bill
That's a transmission that was not automatically assigned to a GM vehicle for service at the beginning,as they sold their own product outright too.
It's dated H for Hydra-matic..0 for 1970...T for Transmission...00604 is the serial #.

[WILMASBOYL78]

Don't think I've ever heard of an NOS automatic transmission...very cool. Do you know what version it is...?? Hi-Shift point..??

-wilma

[Big Block Bill]

I got it with 5 other bare TH400 cases (I have not checked those dates or stamping's yet) in a parts collection I purchased to get a TON of 1966 Impala parts for a SS-396 I'm restoring.

Bill

[Big Block Bill]

I got it with 5 other bare TH400 cases (I have not checked those dates or stamping's yet) in a parts collection I purchased to get a TON of 1966 Impala parts for a SS-396 I'm restoring.

Bill

Out of the 5 remaining cases I have another NOS case w/H0T03563 stamped on it and a used CT dated 68T-5944. If anyone is interested.

Bill

[Mr70]

That's a Service replacement.
HOT03563 stands for:
H=Hydra-Matic..All GM divisions stamped this,regardless of the GM Division using the transmission.
O=1970
T=Transmission
03563=Serial # for Service Use.They started at 00001 and went up to 99999.

[earntaz]

The TH400 I have in my Nova is coded CE-68-2624 with a 490 date -- not really sure what it was born in ... but it shifts just fine ... TAZ :dunno:

[WILMASBOYL78]

The TH400 I have in my Nova is coded CE-68-2624 with a 490 date -- not really sure what it was born in ... but it shifts just fine ... TAZ :dunno:

The CE code in 1968 would be for a Chevelle or Camaro with hi-perf 396...since there were no TH-400's behind the solid lifter big blocks in 68 [except Gibb Novas], that would mean an L-34 or L-35 engine.

the 490 date would be sometime in early April of 1968.

-wilma

[earntaz]

The CE code in 1968 would be for a Chevelle or Camaro with hi-perf 396...since there were no TH-400's behind the solid lifter big blocks in 68 [except Gibb Novas], that would mean an L-34 or L-35 engine.

the 490 date would be sometime in early April of 1968.

-wilma

Thanks Tom -- looks like this is a pretty early tranny. I know that if left in drive at WOT it will shift a skoshi over 5000 RPM ... Craig

[WILMASBOYL78]

You can move that shift point up by changing the governor or modifying springs/weights...I may have a hi-shift point unit in the parts. dept if you are interested:wink:

-wilma

[Markyodb2]

Does anyone know the stall on the CX 69 TH400?

[Mr70]

I believe 2200 RPM.

[Fast67VelleN2O]

Is it possible for a 1970 CW transmission to have no partial vin number?

[WILMASBOYL78]

Is it possible for a 1970 CW transmission to have no partial vin number?

I have seen the partial VIN in 2 locations;

1..on the top side of the pan frame rail, driver's side above shift lever.

2..on the passenger side of the bell housing near the top

most have been in the frame rail location....you will need to have tranny out of the car or have a good mirror/lite to see either location.

**this tranny was only available in the L78 Nova/Chevelle and the LT1 Deuce and Z28. There is typically a pink CW ink stamp on the trans. case.

-wilma

[Fast67VelleN2O]

I have seen the partial VIN in 2 locations;

1..on the top side of the pan frame rail, driver's side above shift lever.

2..on the passenger side of the bell housing near the top

most have been in the frame rail location....you will need to have tranny out of the car or have a good mirror/lite to see either location.

**this tranny was only available in the L78 Nova/Chevelle and the LT1 Deuce and Z28. There is typically a pink CW ink stamp on the trans. case.

-wilma

I looked all over and did not find a vin stamped anywhere. Here's the tag for reference. I'll be listing it for sale soon I guess.

[WILMASBOYL78]

Given the date code of '478'...this was a unit built in April of 1970. Most likely an L78 Nova application...but, could be from a Z28...Deuce would be a long shot. Not sure if they had CW trannys available over the counter...but, if so there would still be an assembly stamp someplace..

do you have the 6 lug converter...??

Here are some images of partial VIN by pan rail...

[Fast67VelleN2O]

Given the date code of '478'...this was a unit built in April of 1970. Most likely an L78 Nova application...but, could be from a Z28...Deuce would be a long shot. Not sure if they had CW trannys available over the counter...but, if so there would still be an assembly stamp someplace..

do you have the 6 lug converter...??

Here are some images of partial VIN by pan rail...

I found the vin this morning when it wasn't so dark out. Its a 1970 Camaro transmission. There is no converter. Vin was stamped right on the bell housing flange edge, near where the oil filter mounts.

[Mr70]

Norwood or Van Nuys?

[Fast67VelleN2O]

Norwood or Van Nuys?


Norwood.

[Jay_Dee_59]

Hello, not trying to piggy back on this just saw it I have a CY with the 6 bolt convertor out of a 73 Z/28 if there is any interest. Larry

It's kind of funny that I know Larry through Ebay transactions and that we both have the same CY code tranny out of a 1973 Z28 lol

This is possibly a dumb question but would a 1973 Camaro CY code tranny be internally identical to lets say a 1969 CY code trans ?

There is a big difference in the engines they would be mated to - 350 hydraulic small block versus a Hi-Po 427 ?

Thank you,
Jerry

[Mr BB Chevy]

Just picked up a 1969 L-71(LX code) still bolted to the matching CY(th400) and 6 bolt converter.