Some cars leave a paper trail; the GM 4T60-E transmission left a name, a year — 1990 — and a place in GM (General Motors)'s list. What follows is what can be said with a source behind it.
The story
The 4T60-E (and similar 4T65-E) is a series of automatic transmissions from General Motors. Designed for transverse engine configurations, the series includes 4 forward gears. The 4Txx family is an evolution of the original Turbo-Hydramatic 125 transverse automatic introduced in the late 1970s and the Turbo-Hydramatic 440 transmission developed in the mid-1980s. The "-E" transmission is electronically controlled and features an automatic overdrive transaxle with an electronically controlled torque converter clutch. The 4T65 is built at Warren Transmission in Warren, Michigan. Gear ratios:
Drive and Driven sprocket combinations and ratios 33 Drive / 37 Driven creates a 0.892:1 ratio 35 Drive / 35 Drive creates a 1.000:1 ratio 37 Drive / 33 Driven creates a 1.121:1 ratio Example - 3.29 diff ratio divided by 1.121 = 2.93 3.29 diff ratio divided by .892 = 3.69
Its place in the line
Where it sits in GM (General Motors)'s history is not in doubt: the Turbo-Hydramatic 125 came before it; the 6T70 followed it. On a showroom list of its day it stood against the Ford Explorer, the Renault Clio, the Honda NSX. Nearby in the GM (General Motors) catalogue sit the 1955 Chevrolet and the 1957 Chevrolet.