OK guys, here is a tough one (at least I think it)...

Is there a a difirence in the bellhousing bolt patterns from a 1998-2000 5.7L and a 2003 5.3L???? Are they both the same LS Series bellhousing design???

ANd to phrase the question another way lets say, would a 4L60e bolt onto both of the above motors with out any problems?

Thanks

 

Thats a ? I'd really like to know the answer to as well?? Being as I got a 4l60 out of a 97 sitting in my garage for the last 2 years because I was told it wouldn't bolt up to my 5.3??

 

simple answer NO the 5.7L 350 trans uses a diff spline converter and only has 6 bolts for the housing. So ya they would bolt up but I dont know what you would do about a converter.

 

had to do alot of research on this awhile back. here you go... one on the left is the old style, one on the right is ls-based truck style. the older on is missing the top bolt hole and has different bolt holes on the bottom, as well as having the 298mm input shaft(the ls-based uses the 300mm shaft). let me know exactly what your trying to do and i'll see if i can help.

 

Well, I am working on a way to do a Manual Conversion that will make me happy... The T56 will not work for me because I want to retain my 4wd sytem so, I have been researching a lot in the past few days and learned of the NV4500 Transmission.

The NV4500 was used in the 1998-2000 2500/3500 (2wd/4wd) series trucks with the 5.7L V8 (and even the diesels) so, I don't see any reason why the NV4500 can't be used on the 5.3L in my truck.

Here are the gear ratios of the NV4500:
1st....................................5.61:1 (Granny)
2nd...................................3.04:1
3rd....................................1.67:1
4th....................................1.00:1
5th.......................................75:1
Reverse.............................5.04:1

Now since the NV4500 is a truck transmission, don't expect to be able to shift it as fast as the T56. BUt, thats ok for me because I just love a manual and I am not looking for my truck to be a 1/4 mile queen... The NV4500 retains all towing abilitys and even gives more towing/off road performance with the added Granny Gear. In fact other then the Granny Gear, the gear ratios are almost the same as the 4L80e I have now!!!

 

Well, made a call to Advanced Adapters and they make the Bellhousing and Flywheel/Clutch kit for what I want to do! And they said the Autotrack T-Case should bolt right up to the NV4500 tranmssion since it has the 32 spline output shaft!!! w00t!!! Now i just have to loo at mounting a Clutch Pedal, I am betting the Avalanche will be a little more tricky then the Silverado for the clutch pedal...