n the early 1980s, emission standards began to raise due to concerns with ozone reduction and city air quality. American automakers, including GM, were pushed to produce engines that would significantly decrease air pollutants. In response, GM began to integrate overdrive transmissions that would help to reduce airborne pollutants. The 700-R4 Turbo Hydramatic was the first of such transmissions and became available for GMC and Chevrolet vehicles in 1982 models. In 1990, the 700-R4 was renamed the 4L60 Turbo Hydramatic.
Two years after the renaming the 4L60, GM made further improvements to the transmission by replacing the throttle valve (TV) cable and governor with electronic controls. Hence, the name was slightly changed to 4L60E to denote the inclusion of these computer controls. The name 4L60E formally standards for 4-speed, longitudinal applied (rear-wheel drives), 6000 lbs. gross vehicle weight rating, electronically controlled. Almost all GM vehicles using rear wheel drives have 4L60E transmissions (SEE CHART VEHICLES USING 4L60E). Currently, GM does not designate the “E” on the majority of 4L60 models since most are electronically controlled. GM also uses the alternative RPO (regular production option) code M30 as a designation for the 4L60E.
The most obvious identifying marks differentiating the 4L60E from its predecessor (4L60) is the absence of the TV cable outside the casing, a six-bolt rear output.
There have been a variety of slight upgrades to the 4L60E. Early models had a 6-vane pump. However, these had issues with pulsations and durability. To address these complications, 10- and 13-vane pumps were designed. These can be installed on earlier models. Traditionally, GM has had problems with transfer case failures. Owners of GM 4WDs have especially witnessed 4L60 transfer case issues. In 1996, this problem was significantly reduced by the creation of a removable bell housing. The updated housing successfully balances the flexing and weight levied on the transmission. Another addition to the 4L60E was a 300mm torque converter that boasted higher capacity intervals. Complementary 300mm pumps and input shafts rounded out the improvement.
|4L60E TURBO HYDRAMATIC|
|WEIGHT||146 lbs. (dry)|
|GEARING RATIOS||3.059, 1.625, 1.0, .696, R – 2.29|
|MAX TORQUE||360 ft·lbf (488 N·m)|
|FLUID REQ.||8.4 quarts (9.64″ torque converter) 11.4 quarts (11.81″ torque converter)|
|ENGINE COMPATIBILITY||90º “Small & Big Blocks” I6, V6, & V8|
GM’s 4L60 and 4L60E transmissions are among the most popular and enduring transmissions in the world. The overall design and internal shifting of the unit are commonly regarded as a work art. When properly tuned, they offer durability, amazing performance, and significant reductions in engine speed while operating in overdrive. For this reason, the 4L60E is a favorite for hobbyist and enthusiasts. A variety of aftermarket parts and specialty kits are available to upgrade features of the transmission.
The 4L60 and 4L60E are essential the same. The main contrast is that the 4L60E’s valve body components are completely computer operated. One main purpose in introducing these computed aid controls was to improve shifting, fuel consumption, and torque conversion. If one is trying to retrofit a 4L60E to a vehicle model before 1992, expect expensive or challenging work due to the modifications required.