GM 4L80-E transmission

The 4L80-E (and similar 4L85-E) is a series of automatic transmissions from General Motors. Designed for longitudinal engine configurations, the series included 4 forward gears. It was the 4-speed electronically commanded evolution of the 3-speed Turbo-Hydramatic 400, first produced in October 1963. 4L80-Es were optioned only in Chevrolet/GMC pickups, vans, and commercial vehicles, and the Hummer H1. It was also adopted by Rolls-Royce in 1991 and modified after extensive testing,^[1] and used initially in the Bentley Continental R, and subsequently other Rolls-Royce and Bentley vehicles. The 4L80 and 4L85 were built at Willow Run Transmission in Ypsilanti, Michigan.

4L80-E/4L85-E
Overview
Manufacturer	General Motors
Production	1991–2009
Body and chassis
Class	4-speed longitudinal automatic transmission
Chronology
Predecessor	Turbo-Hydramatic 3L80 / THM400
Successor	6L90

Gear ratios

1	2	3	4	R
2.48	1.48	1.00	0.75	2.07

4L80-E

A Hydra-Matic 4L80 transmission at the Ypsilanti Automotive Heritage Museum

The 4L80-E (RPO MT1) is rated to handle engines with up to 440 ft·lbf (597 N·m) of torque.^[2] The 4L80-E is rated to a maximum GVWR of 18,000 lb, depending on the axle and vehicle.^[3]

The 4L80-E uses two shift solenoids, initially called Shift Solenoid A and Shift Solenoid B; they were later changed to comply with OBD-II regulations to 1-2 shift solenoid and 2-3 shift solenoid. By activating and deactivating the solenoids in a predetermined pattern by the PCM, four distinct gear ratios can be achieved. The shift solenoid pattern, also sometimes referred to as solenoid firing order, is as follows:

Shift solenoid pattern

	1-2 solenoid	2-3 solenoid
1st gear	on	off
2nd gear	off	off
3rd gear	off	on
4th gear	on	on

No power results in 2nd gear as "limp home mode."

Applications

• 1991–2007 Chevrolet C/K/Chevrolet Silverado/GMC Sierra 2500 and 3500
• 1991–2007 Chevrolet/GMC Suburban/GMC Yukon XL 1500 and 2500
• 1991–2009 Chevrolet Van/Chevrolet Express/GMC Savana 2500 and 3500
• 1995–1999 Chevrolet Tahoe/GMC Yukon 6.5L Diesel
• 2002–2006 Chevrolet Avalanche 2500
• 1992–2006 Hummer H1
• 1992–1998 Rolls-Royce Silver Spirit/Spur II, III, IV
• 1991–1992 Bentley Eight
• 1991–1997 Bentley Turbo R
• 1991–2002 Bentley Continental R/S/T
• 1999–2006 Bentley Arnage Red Label / Bentley Arnage R/RL/T
• 1993–1996 Jaguar XJS V12
• 1994–1997 Jaguar XJR
• 1993–1997 Jaguar XJ12 / Daimler Double Six
• 1996–1999 Aston Martin DB7

4L85-E

The 4L85-E (RPO MN8) is rated to handle vehicles with up to 690  ft·lbf (935 N·m) of torque.^[4] The 4L85E is rated to handle vehicles with a GVWR of up to 18,000 lbs (dependent on axle ratio and vehicle)^[5]

Applications:

• 2002–2006 Chevrolet Avalanche 2500
• 2001–2006 Chevrolet Suburban / GMC Yukon XL (8.1L Vortec only)
• Chevrolet Express / GMC Savana with Duramax Diesel or 8.1L Vortec
• Rally Fighter

See also

• List of GM transmissions

References

1. Adcock, Ian (1992). Bentley Continental R. London: Osprey Publishing. p. 113. ISBN 185532-260-9.
2. "Powertrain Control Solutions - Factory New Transmissions". Archived from the original on 2013-12-22. Retrieved December 22, 2013.
3. GM Powertrain. "07 Hydramatic 4L series". General Motors. Retrieved January 5, 2014.
4. "Supermatic 4L85-E 4 Speed Auto Transmission: 19300175 | Performance".
5. GM powertrain. "07 Hydramatic 4L Series Specs". General Motors. Retrieved January 5, 2014.