A 4-speed version of the 125 was created for the 1985/1986 GM C platform (FWD)/GM H platform (FWD) cars, the Turbo-Hydramatic 440-T4. Many parts were identical to the 125, though it was generally stronger and included an overdrive fourth gear. This transmission was first used in GM's 1985 Buick Park Avenue, Oldsmobile 98, and Cadillac Deville. In 1986, after switching to FWD, the Buick LeSabre, Oldsmobile Delta 88, and later, the Pontiac Bonneville also used this transmission. A special strengthened F-7 version was also used for the 1987–1992 Cadillac Allanté.
One unique feature of this transmission is its use of both a modulator valve and a throttle valve (TV) cable. Most transmission either use one or the other to control shift points and shift smoothness. On the Turbo 440-T4, the TV cable exclusively controls the shift points, while the modulator valve controls the shift feel. This feature makes it very easy for a home, "shadetree" mechanic to adjust the transmission shift points with minimum affect on the shift feel.
The 440-T4 was later renamed the 4T60.
The electronically-controlled 4T60-E was introduced in 1988. By 1991, all 4-speed front wheel drive automatic GM cars used this unit. It would become the basis of the GM 4T65 transmission, still used today.
A heavy-duty version, the 4T60 HD was introduced in 1991 and produced through 1995 for the supercharged GM 3800 engine.
* The GM LG3 and LN3 3.8L V6s
* THM 440-T4
o 1984–1990 G-body
o 1988-1999 most front-wheel drive GM cars
o 1987–1992 Cadillac Allanté