Mercedes-Benz 4G-Tronic transmission

Mercedes-Benz W4A 040 · W4A 020
W4A 028 · W5A 030
Overview
ManufacturerDaimler AG
Production1979–1996
Body and chassis
Class4-speed longitudinal automatic transmission
Chronology
PredecessorMercedes-Benz first series automatic transmission
Successor5G-Tronic

Mercedes-Benz 4G-Tronic transmission is the unofficial name given to the transmission by car enthusiasts. It was produced from 1979 to 1996 in W4A 040, W4A 028 (both type 722.3), W4A 020 (type 722.4), and W5A 030 (type 722.5) variants.

The W4A 040 and the W4A 020 were used until mid-1996. The W4A 028 variant was used for off-road applications (RWD and 4X4). The W5A 030 is basically the same transmission with an additional electrically controlled 5th gear overdrive section attached to the main body in a separate housing; it was available as an extra charge option. All 4G-Tronics were succeeded by the more modern and economic 5G-Tronic (Type 722.6) transmission that features an integrated 5th gear overdrive ratio, torque converter lock-up and fully electronic control.

Gear Ratios[a]
Gear
Model
R 1 2 3 4 5 Total
Span
Span
Center
Avg.
Step
Compo-
nents
W4A 040 I · 1979 −5.139 3.676 2.412 1.436 1.000 3.676 1.917 1.543 3 Gearsets
3 Brakes
2 Clutches
W4A 020 · 1982 −5.669 4.249 2.408 1.487 1.000 4.249 2.061 1.620
W4A 040 II · 1985 −5.586 3.871 2.247 1.436 1.000 3.871 1.967 1.570
W4A 028 · 1990 −5.586 3.871 2.247 1.436 1.000 3.871 1.967 1.570
W5A 030 · 1990 −5.586 3.871 2.247 1.436 1.000 0.750 5.161 1.704 1.507 4 Gearsets
4 Brakes
3 Clutches
  1. ^ Differences in gear ratios have a measurable, direct impact on vehicle dynamics, performance, waste emissions as well as fuel mileage