GM 4T40 transmission

4T40-E/4T45-E
Overview
Manufacturer	General Motors
Production	1995–2010
Body and chassis
Class	4-speed transverse automatic transmission
Chronology
Predecessor	Turbo-Hydramatic 125
Successor	GM 6T40 transmission

The 4T40-E and 4T45-E are a series of automatic transaxles from General Motors. Designed for transverse engine configurations, the series includes 4 forward gears. The 4Txx family replaced the Turbo-Hydramatic 125 transverse three speed automatic introduced in 1980.

The "-E" series is electronically controlled and features an automatic overdrive transaxle with an electronically controlled torque converter clutch. Since the non-electronic versions of these transmissions does not exist, it is conventional to refer to these models as simply 4T40 and 4T45, leaving out the "-E".

The 4T40 and 4T45 were assembled at Windsor Transmission in Windsor, Ontario, Canada.

4T40

The "MN4" 4T40E is able to handle vehicles up to 4000 lb (1814 kg) GVWR. The final drive ratio can vary depending on the cars curb weight and engine power output. 3.91, 3.63, 3.29, 3.05, 3.69, and 3.42 are all of the available ratios used in the 4T40 (and 4T45) transmission; Made possible by using combinations selected from 3 different sprocket combinations (32/38, 35/35, 33/37) and 2 differentials (3.29, 3.05). It is designed for 1.5–3.1 L engines producing up to 190 ft·lbf (258 N·m) of torque.

Gear ratios:

1	2	3	4	R
2.95	1.62	1.00	0.68	2.14

Applications:

1999-2002 Daewoo Nubira
1999-2002 Daewoo Lanos
1995–2005 Chevrolet Cavalier
1995-1996 Chevrolet Corsica
1995–2005 Pontiac Sunfire
1997–2003 Chevrolet Malibu
1999–2005 Pontiac Grand Am
1999–2004 Oldsmobile Alero
1997–1999 Oldsmobile Cutlass
2000-2004 Saturn L-Series

4T45

The "MN5" 4T45E is able to handle vehicles up to 4,500 lb (2,041 kg) GVWR. Final drive ratios include 3.63, 3.29, 3.05, and 3.91. This same transmission is used in the Saturn Vue Green Line hybrid vehicle with the addition of an auxiliary oil pump and hybrid-aware electronics. It is designed for 3.0–3.5 L engines producing up to 205 ft·lbf (278 N·m) of torque, but was also commonly mated to some versions of GM's 4-cylinder Ecotec line.