Thread: HD Diff???

Originally Posted by 05grndprix

yea i donno i dont think its different if it changed that would probably mean the ring gear is different and i know thats not different but i could be wrong

Ring gear is the same in all 4T65Es, and there are three possible differential ratios from GM. Just because it didn't change doesn't mean the ratio didn't change. What does change the ratio is the size of the sun gear and likewise the size of the planetaries.

May want to make sure before you go slapping it in.

Originally Posted by Scimmia

I believe all 3800 GPs used a 3.29 diff.

Up to 03, I'm pretty sure that's the case. But 04+ I don't have any info on, so that's why I figured he should check it out.

Sun gear info:

42 Teeth = 2.86 Ratio
38 Teeth = 3.05 Ratio
34 Teeth = 3.29 Ratio