4L60E Are They All The Same?
There have been several different versions of the 4L60E over the years. They started in the mid 1990’s and continued through the early 2010’s. Over the years there have been some changes that have happened but at the end of the day the transmission still carries the 4L60-E casting.
1-piece case 4L60E was introduced in 1993. This is the predecessor of the 700R4. The cases look very similar with the only difference being on the passenger side, there is the transmission main body connector for the wiring harness and transmission controller. This transmission came with a 13-pin main harness connector. The input shaft size is 298mm. The bell housing has 6 bolts and is designed to bolt up big block and small block Chevrolet engines.
See image 298mm, 298mm#2
2-piece case 4L60E was introduced in 1998. This transmission shared a lot of the same features as the 1-piece case 4L60E such as the 298mm input shaft, the 13-pin main harness connector and the 6-bolt bellhousing for big block and small block Chevrolet. The biggest difference is the bellhousing will bolt to the main body of the transmission. The bell housing is also completely round. This will eliminate the standard dust cover that was needed for the 1-piece case design. The same torque converter will fit this transmission as well as the 1-piece case 4L60E and the 700R4 transmissions.
See image 298mm#3
2-piece case 4L60/65E was introduced in 1999. This transmission changed a few things from the previous versions. The input shaft was changed to 300mm, the bell housing was changed to add the 7th bellhousing bolt for the LS engines. You can see in the image it has the 12 o’clock bolt hole that the LS engines utilized. Having a longer input shaft, the bell housing for this transmission is deeper than the previous models. The torque converter also has a longer pilot that will fit in the back of the crankshaft. The 4L65E uses a 13-pin main harness connector.
See image 300mm, 300mm #2
2-piece case 4L70E was introduced in 2007. The transmission still used the same 300mm input shaft, but the change was in the main harness connector. The 4L70E came with either a 15 or 17 pin main harness connector.
15 pin- allowed for the use of an input shaft speed sensor
17 pin-allowed for the use of an input shaft speed sensor and an internal PRNDL switch
Swaps and converter capabilities.
While the 4L60E (298mm) can bolt up to an LS engine it will be missing the 12 o’clock bellhousing bolt on the bell housing and will require a torque converter pilot spacer to make up the difference in height for the late model engines.
4L60/65/70E (300MM) will bolt up to a small block or a big block Chevrolet the torque converter will be too tall to allow the proper converter pull back. One of two things will need to be done for this swap to work. Either an engine to transmission spacer plate or a custom torque converter. Yank Performance offers custom converters that are designed for a 300mm input and has a short, small big block Chevrolet pilot.
