4T60-E slip from 1st to 2nd gear
 

Guys,

my Trans. slip in the 1st gear. Oil is okay.

If i accelerate from 0mph the rpm goes up quick, the mph really slow.

At 2500rpm the trans slip like it would shift to neutral.

If i get of the gas pedal and the rpm goes down the trans shift into the next gear.

Has anybody an idea how to fix the problem?

Thanks' in advance!!!