bonedizzle

iTrader: (9)

What are the differences, if any, of the 4l60e trannies on a SBC compared to the ones used on the LS? I am having a very difficult time finding a 2wd 4l60e transmission to mate to my 5.3 locally here in the midwest, as every truck and SUV has 4x4.

There isn't a single 2wd 4l60e from an LS in my local junkyard. There are a couple 98+ vans with the 350 SBC with 2wd. I was wondering if those are the same as far as input shaft, output, ect. I know I read about some differences between the LS models vs the v-6 ones so I don't want to try and make that work.

mrvedit

The SBC, V6, C5-Vette and ALL pre-98 4L60E have the 298mm input shaft and are often referred to as "LT" compatible transmissions.
For "direct" bolt-up to an LS engine, you need a '98+ 4L60E/4L65E/4L70E with a 300mm input shaft; these transmissions also have a bolt hole in the 12 O'clock position in the bell housing.
Later model '96+ "LT" style 298mm input shaft 4L60E will bolt up to an LS engine with the addition of a pilot extender on the flexplate and enlarging the holes on the flexplate or getting a dual-pattern flexplate.
Absolutely avoid the '94 and '95 models as they are electrically incompatible with every LS PCM.
IMO, installing any high mileage LT style 4L60E makes no sense as the LS engine will quickly shred it.
GM strengthen the trans in '98 for the LS1 engine and again in '03 for the LS2 engine.

These thread have more info and pics:
https://ls1tech.com/forums/automatic...uld-i-buy.html
https://ls1tech.com/forums/automatic...s1-4l60-e.html
https://ls1tech.com/forums/automatic...urus-help.html

bbond105

You could get a 4X4 trans and change the output shaft and add a tail housing.

mrvedit

You could Mr Bond, but not most people that have never opened a trans. Unless the trans was recently rebuilt, it is a slippery slope from changing the output shaft to a complete rebuild.