Thread: 4t65e-hd in a l36

hi i was just wondering wht is neede to swap in the hd tranny into a l36 is it just the gear ratio that needs to be changed in the pcm thanks

come on people sombody please help

gtp axles and ratio change in the pcm. what i would do is just swap gtp axles and the hd dif into your stock tranny, then you'll still have 3.29s. cause if you think your l36 is a dog now, wait til its running 2.93s

Your trans is the same as an HD trans in almost all ways.

The output shaft is a little shorter/thinner
The diff is smaller
The diff cover is smaller for the smaller diff
You have 35/35 drive/driven gearing instead of 33/37.

If you did the HD upgrade (Diff, output shaft, diff cover and shorter passenger axle) then you'd have a HD trans wtih 3.29 gear ratio.

Originally Posted by BillBoost37

Your trans is the same as an HD trans in almost all ways.

The output shaft is a little shorter/thinner
The diff is smaller
The diff cover is smaller for the smaller diff
You have 35/35 drive/driven gearing instead of 33/37.

If you did the HD upgrade (Diff, output shaft, diff cover and shorter passenger axle) then you'd have a HD trans wtih 3.29 gear ratio.

thanks guy cuz i found a hd tranny out of a buick park ave ultra for 100 bucks but the reason i wanted to swap was because my tranny is acting weird every now and then it will bog then bang into second gear any idea what that is ive herd it could be the input clutch piston any other ideas wht ot could be