View Full Version : Question on towing capacity or rating of a truck->

Jeff H
01-21-2003, 02:33 PM
I remember seeing a discussion about towing car trailers somewhere but I can't remember where. Anyway, from what I remember, some states have some hefty fines for towing more than what a truck is rated to tow. I'm looking at buying a 91 SS454 pickup for my every day vehicle, but I also would want to be bale to tow my 69 Z28 to shows when it's done. The truck has the engine and trans that can tow an enclosed car trailer, but I don't think it's rated for that much. Is there any way to legally increase the towing capacity of a vehicle like this? If I did suspension and brake upgrades could the vehicle then be certified for a higher capacity? If there's a risk of getting fined, might as well spend the money doing the upgrade anyway. Does anybody have any thoughts on this?

I did a search and found the old thread here I was thinking about. I'm still wondering if it's possible to increase the vehicles towing capacity though.

01-21-2003, 05:57 PM
Well Jeff, I'll give you my take on this.

In all honesty the "towing capacity" is all related to engine, transmission and rear end ratio. If you are considering a 454 you should not have any problem unless it is a manual tranny or a rear end in the low 3's. Let's assume the 454 does have the automatic and a rear gear of 3.55. I would guesstimate you would be fine up to about 8,500 pounds, maybe even higher, which should cover your Z and the enclosed trailer. I do not believe suspension mods will in itself give you any major additional towing capacity, but would help keep the entire rig more level probably.

If the truck in question doesn't have it, make sure you install an external tranny cooler and possibly an oil coller as well. Good luck.

EDIT - one other point of note is the wheelbase of the truck. I assume this SS 454 is one of the short wheelbase models. I have done a lot of towing with those types of trucks and this shorter wheelbase definitely makes a difference in "leveling" in comparison to the long wheelbase models. Suspension upgrades would definitely help if this is the case.

01-21-2003, 07:15 PM
I think the "towing capacity" that Jeff is questioning is the GVCW. It seems the DOT in all states are becoming more and more stringent, especially since 9-11, and it's only gonna get worse.

As far as I know, there is no way to increase your GVCW, except to upgrade to a different vehicle. I believe it takes into account the drivetrain, chassis, brakes, and weight of the vehicle itself. The weight of the truck is one of those wierd little things, as often times the lighter truck, in the same weight/chassis combo, will have the higher GVCW. A good is example is like some of the gas rigs having slightly higher ratings than their diesel counterparts because they are lighter.

What is the GVW/GVCW of your SS454? If I had to guess, I would say you would be real close or a little over with a 20ft enclosed and your Z, but wouldn't have a problem with just an open trailer and your Z.

Jeff H
01-21-2003, 08:30 PM
I think the brake rating based on the VIN says it falls in the 6000-7000 lb class. The SS454 actually has the heavier frame even though it's considered a 1/2 ton. I'm more worried about the legal aspect of things. If my registration says it can tow 6000 lbs, is there a legal way to increase it's towing capacity to say 7000 or 7500 so it could legally tow an enclosed trailer and car? The engine and transmission should have no problem towing either of those weights, but if your weight exceeds the paperwork, hello fine! And the truck has the 4.10 rear with the 4L80E overdrive trans so it's set up great for occasional towing.
I just found the ratings for the truck and with the 4.10 rear it's towing capacity is 10,000 lbs. The 3.73 rear is rated at 9500. It looks like I'll be buying this truck, what a cool daily driver with some muscle.

01-21-2003, 09:06 PM
In Missouri your tags have to cover the weight of the truck and the trailer combined and loaded. You can put 18,000 lb tags on a 1/2 ton pickup if you want. The pits of the deal is you can buy any suv and tag it as a car and pull or haul all you want without any special tags. go figure.

01-21-2003, 10:58 PM
Here is an interesting thread concerning towing I followed over on the SuperStock site: THREAD (http://www.superstockforum.com/showthread.php?s=&threadid=3819)

I think most states are starting to crack down on anything with a trailer, partly because of 9-11, but mostly because they see $$$.

01-24-2003, 03:08 PM
Jeff, check your local and state laws. Your tow vehicle and trailer must be legal there unless it is going to be used for commercial use. Still check with a local truck dealer about upgrades that would increase the GVWR. You are better off though buying a 3/4 ton truck or even and extended cab 1/2 that has a bigger towing capactiy than that SS454. You will be borderline using that truck, especially the brakes, they stink! My 98 Tahoe does pretty good pulling my Camaro but stopping is another story, even with electric brakes on the trailer. Below is a link to where this was discussed before......................RatPack...............

http://www.yenko.net/ubbthreads/showflat.php?Cat=&Board=UBB1&Number=16089&page=19& view=collapsed&sb=5&o=&fpart=1

Jeff H
01-24-2003, 06:00 PM
The truck is now sitting in my garage, I bought it. The SS454 is built on the 3/4 frame. I'm not too concerned about it yet, my car won't be done for another year. I know that the Tahoe's have bad brakes and they weigh a bit more. One of our local racers uses his Tahoe to tow his 97 SS. Thanks for the info, since the truck will be my daily driver, I didn't want something that was too long or a pain to deal with and this should serve the purpose well.

01-25-2003, 12:46 AM
Good purchase Jeff, I would highly recommend changing the front brakes and adding discs to the rear. Those 88-98 trucks used the same crappy brakes as the Tahoes and Suburbans did. My 2001 Suburban will stop in 2/3 the distance my Tahoe will when towing my Camaro.................RatPack..............

01-25-2003, 12:57 AM
I have learned over the years that the best way to save the truck brakes is to make sure the trailer does most of the slowing. If the brake controller is properly set you can take it a lot easier on the front truck brakes. We tow about 6000 miles a year up and down mountain passes and the trailer brakes are vital. /ubbthreads/images/icons/grin.gif Jim