Firebird V8-305 5.0L VIN E TBI (1989)
On January 05, 1993 (Julian Date 005) HYDRA-MATIC 4L60 transmissions were built with an improved design 3-4 clutch. The improved design
consisted of combining the 3rd and 4th clutch ring retainer plate (Ill. 652), the 3rd and 4th clutch apply (stepped) plate (Ill. 653) and the 3rd and 4th
clutch (steel) plate (Ill. 654C) into one 3rd and 4th clutch apply plate (Ill. 653) Figure 1. The 3rd and 4th clutch steel plates are also thicker and the
backing plate selection has changed as noted in Figure 2.
NOTE:
In the overhaul repair kits for the HYDRA-MATIC 4L60 there are two (2) sets of 3rd and 4th clutch fiber plates. The two 3rd and 4th clutch fiber plates
are calibration sensitive and interchanging the wrong plates may cause premature failure. The chart shows which models should use the plates labeled
"2050" Figure 3.
