General Motors 4L60E

Transmission general data

The 4-speed family of GM transmissions named as TH700R4 (Turbo-Hydramatic) 4L60E/ 4L65E has been launched in production in 1982 and after some minor changes was renamed as 4L60. This 4-speed transmission for RWD cars was constructively based on the popular HydraMatic 700R4, but produced at the GM factory in Toledo (Ohio) and proved to be very efficient. This gearbox was used on RWD 4WD cargo vehicles and off-road vehicles with the engine from 3 up to 6 liters. It is the primary transmission for Hammers and also was used on Suzuki Vitara and SAAB. In 1996, engineers introduced a significant update and as a result the valve body control became electronic and it was named as the 4L60-E.

But the main innovation leading to high level of sales was the solenoid-regulator allowing soft shifting of gears and fast acceleration as well as control over the torque converter (TC) lock slippery. By 2001 the enhanced version of the 4L65E had been released. This modification was intended for the torque equal to 515 Nm. The next modifications of hydraulics and electronics and were introduced in 2001 -2003.

Technical issues and repair guidelines

The TC lock-up clutch is the first element to wear out leading to oil contamination and clogging of solenoids with sensors. The TC unit in this transmission operates quite intensively, accelerating a powerful car with the help of the lock-up when the driver strongly pushes the throttle pedal to the floor.The clutch drum and the brake band frequently turn out to be a major issue for Hammers H2 and H3 with engines over 5 liters.

The first overhauls of the 4L60 consist in cleaning of the valve body (VB) and solenoids, repair of the TC unit with replacement of the lock-up unit and some spare parts. If the ATF and filter are replaced often and in due time, then the transmission operates properly for a long time. Solenoids are replaced as a full kit when their operating period comes to an end.

After covering 150-200 thousand kilometers the following units fail due to the transmission ageing (and first of all because of contaminated oil):

- Valve body separate plate

-Separator of the overrunning clutch, Forward (Input) Clutch and Low/Reverse.

Intensively operating rear planetary gear is usually replaced on old cars. The kit of valve body gaskets is one of the most frequently ordered spare parts. The kit of bearings is also ordered for the transmission reassembly. In general, these automatic transmissions are robust and consistent and after a standard overhaul they will serve for a long period of time.