Transmission blown .... again :(

[HumminNBoatin']

I know a guy who did a 4l80e conversion to his for the same exact reason as you. However he had to take it to a custom shop to have it done. He is located in Indianapolis. Where are you located?

When doing a 4l80e conversion you have to have a new center crossmember made for the truck and new driveshafts made.

The 4l65e is a good transmission. But its only rated to take like 385ft. lbs and roughly the same 385HP. In most rear wheel drive vehicles that are lighter in weight they work just fine and when you lay the power down the tires break loose first. But in a HUMMER with AWD something has got to slip and it takes alot more power than 385ft. lbs to break 4 tires loose from the ground under a 7K# truck.

If you dont lay the throttle down all the time a stock trans will do fine for a while. But if you like to hammer down it will fail in no time.