Thread: 4t60e hd diff swap

I am getting the same tranny. But I want to swap in a hd diff.

Thank you.

Originally Posted by TimMcCallum

Thank you.

The HD differential from the 4T65 can be used if the diff housing and HD P/S axle are used. There is also the HD diff from the 4T60 found in the Riviera in 1996 but it's a little more difficult to locate. The big issue plaguing the 4T60 is the pump design...if you plan to rev over 6000rpm the pump will cavitate causing loss of hydraulic pressure and thus burning up the trans. Also, the vacuum modulator fails causing no/low transmission line pressure...kind of like the PCS in the 4T65 failing. However, the modulator on the 4T60 is cheap and easily replaced whereas the 4T65 requires you to go inside to replace it. The 4T60 has a 7/8" chain factory as well. With upgraded clutches and a few hard parts, it can hold the power just like a 4T65 with the same mods...but you'll never be ever to rev it as high. My 4T60 in my GP lasted for like 10k hard miles when I was top swapped and only died due to pump failure. I installed a new pump and it ran like a dream...but I still swapped it for a 5 speed...because 5 speed is awesome.

How hard is it to do the 5 speed swap? Haha. And mines got a n/a gt

The entire build including breaking stuff and rust repair took about 200 hours. The 5 speed swap itself isn't hard...but it does require a lot of fabrication skills. I went through the engine and fixed a lot of rust and cleaned and upgraded the audio and just about everything else that could be done. LOL

The trolling is so strong.

Okay so im thinking just the diff needs swapped. I really dont know what im looking at but from what I can see just the diff needs swapped and ill be golden. Ide like to put an hd diff into it though because I dont want this to happen again

I messaged you. Im gonna pop the diff out and take pics. Before and after taking it out. I was going to last night but my phone died and it was cold and late so I said screw it ill wait till morning