The following pages contain information on specific transmission models from the 4T60, 4T60E and 4T65 family(4T40/4T45 and 4T80 information may be in the works, stay tuned). For now, it is NOT an all-inclusive list, but any missing information would be appreciated.

Miscellania:

4T60E Differentials with an asterisk are "fine pitch" final drives. Sun gears, internal ring gears, and pinion gears are NOT interchangeable with other final drives.

4T65E with "IMS" have the newer type of shifter position sensor, called the "Internal Mode Switch", as opposed to the style found on 4T60E and early 4T65E transaxles.

4T65E Stall Speed Info:

these are approximate stall speeds based on the K-factor and TC size. YMMV, but they should give a good estimate as to which ones will stall higher or lower.

245-115 = 1340
245-163 = 1900
245-177 = 2060
245-180 = 2100

258-115 = 1410
258-133 = 1630
258-155 = 1900
258-164 = 2010
258-179 = 2200

4T80 General Info:

Maximum Engine Torque: 300 Ft-Lb
Maximum Gearbox Torque: 461 Ft-Lb
Maximum Gross Vehicle Weight: 4750 Lb
265mm Torque Converter
269 Lb Dry
295 Lb Wet
15 Quart Capacity

gearing:
2.69
1.626
1.0
.681

39/39 Chain Ratio
Differentials: 2.84, 3.11, 3.48, 3.71

maximum shift speeds: 6400RPM

All have a 39 tooth input speed reluctor?
All have a 31 tooth output speed reluctor(VSS)?

1995 G-Body(Aurora) 4T80E
AKN 3.48:1 FDR (has higher shift points)
ZYN 3.71:1 FDR

1997-up
G:
MDN (has higher shift points)
MSN

1997-up
E & K: AAN(has higher shift points)
K: MLN