Curt from Monster Transmission uses some 4L80E transmission cores to show the external differences between the early and late models.
- The early models with a year range of 1990-97 had coolant line fittings that are close to each other. Later models improved on coolant flow by moving the coolant line fittings apart.
- The early model case does not have a top bolt hole which will bolt up to 5.7 to 350 engines. Later models featured a top bolt hole to bolt up to LS engines.
- Early models also have a short linkage shaft and the NSS was in the shift console while the later 4L80’s had an NSS on the transmission and a longer linkage shaft.