LT1 vs. LS1 4L60E
05-03-2013, 10:03 AM
#1
Teching In
Thread Starter
Join Date: May 2006
Location: Plano Texas
Posts: 8
Likes: 0
Received 0 Likes
on
0 Posts
LT1 vs. LS1 4L60E I have looked through several pages and have not found anything certain.
Does anyone know the differences between the LT1 and the LS1 4L60Es for swap out purposes?
I want to replace my 96 unit with an LS1 unit and am not sure what changes need to be made. Because those seem to be more available.
Thanks for any help.
Does anyone know the differences between the LT1 and the LS1 4L60Es for swap out purposes?
I want to replace my 96 unit with an LS1 unit and am not sure what changes need to be made. Because those seem to be more available.
Thanks for any help.
05-03-2013, 12:46 PM
#2
Moderator
There are quite a few differences which will make using the newer style 4L60E difficult, although not impossible.
Pre '98 4L80E all were 298mm input shaft; the '98+ V8 (LSx) are all 300mm input shaft. This is a big difference, which requires different converters and bell housings. The newer 4L60E will require a 300mm converter. When you then try to bolt it up, the converter will engage into your crankshaft and leave about a 3/4" gap between the bell housing and engine block. GM Performance makes a kit to fill that gap with a spacer for the entire bell housing. (Sorry, forgot part #, but Summit sells it.)
However there may be other problems too - your PCM might not properly control the trans. The newer 4L60E use a PWM lockup clutch and a different 3-2 downshift solenoid that earlier years. The transition occurred between '95 and '96 and I don't know what you PCM supports. Mods or a different valve body would solve it, but it is another potential stumbling block.
Most people ask the opposite - using a older trans in an LS1. Here is such a post. Note my picture of the different input shafts which tell you if you have a 298mm or 300mm trans:
https://ls1tech.com/forums/automatic...urus-help.html
Pre '98 4L80E all were 298mm input shaft; the '98+ V8 (LSx) are all 300mm input shaft. This is a big difference, which requires different converters and bell housings. The newer 4L60E will require a 300mm converter. When you then try to bolt it up, the converter will engage into your crankshaft and leave about a 3/4" gap between the bell housing and engine block. GM Performance makes a kit to fill that gap with a spacer for the entire bell housing. (Sorry, forgot part #, but Summit sells it.)
However there may be other problems too - your PCM might not properly control the trans. The newer 4L60E use a PWM lockup clutch and a different 3-2 downshift solenoid that earlier years. The transition occurred between '95 and '96 and I don't know what you PCM supports. Mods or a different valve body would solve it, but it is another potential stumbling block.
Most people ask the opposite - using a older trans in an LS1. Here is such a post. Note my picture of the different input shafts which tell you if you have a 298mm or 300mm trans:
https://ls1tech.com/forums/automatic...urus-help.html
05-03-2013, 01:40 PM
#3
Teching In
Thread Starter
Join Date: May 2006
Location: Plano Texas
Posts: 8
Likes: 0
Received 0 Likes
on
0 Posts
Wow! Thanks for the great reply.
I Have 1996 Z28 with a used up 4L60E. When looking on line here there seem to be many more well built used ones for sale from LS1 cars.
I am not sure if I can save my trans. Someone "Helped" me out when it started slipping. I know there was some drilling involved. It was a rediculously hard hit from 1st to 2nd. I am not looking for that. It maybe neccessary with 500 wheel.
I Have 1996 Z28 with a used up 4L60E. When looking on line here there seem to be many more well built used ones for sale from LS1 cars.
I am not sure if I can save my trans. Someone "Helped" me out when it started slipping. I know there was some drilling involved. It was a rediculously hard hit from 1st to 2nd. I am not looking for that. It maybe neccessary with 500 wheel.
05-03-2013, 02:20 PM
#4
Moderator
Perhaps it had the B&M shift kit installed which only serves to give rock-hard shifts and destroy the trans. Of course if it was already slipping, the options are limited.
With 500 rwhp you would quickly ruin a stock 4l60e too; remember it is already 10 years old and was designed for maybe 325 rwhp. You really don't want to blow a trans, even a free one, because it will also contaminate the converter and cooler. (The converter MUST then be sent out to be opened and cleaned; the cooler simply replaced.)
You are fortunate that sponsor Jake Performance is very close to you in Sanger, TX. They could rebuild your current trans or sell you one ready to go that can handle your power level. Close is good because it reduces shipping and core charges.
If you are comfortable rebuilding it yourself or with a local trans friend, we would be happy to help you select upgraded parts.
With 500 rwhp you would quickly ruin a stock 4l60e too; remember it is already 10 years old and was designed for maybe 325 rwhp. You really don't want to blow a trans, even a free one, because it will also contaminate the converter and cooler. (The converter MUST then be sent out to be opened and cleaned; the cooler simply replaced.)
You are fortunate that sponsor Jake Performance is very close to you in Sanger, TX. They could rebuild your current trans or sell you one ready to go that can handle your power level. Close is good because it reduces shipping and core charges.
If you are comfortable rebuilding it yourself or with a local trans friend, we would be happy to help you select upgraded parts.
