The 4L80E and 4L85E are GM's HD 4-speed automatics. The 4L85E is a strengthened version. Here's exactly what's different.
Shop the parts for this fix
Doing the whole job? 4L80E Master Rebuild Kit - Frictions & Steels, Gaskets & Seals, Filter, Shift Kit, Servo, Solenoids (6-Piece) — $246.99 $259.99 (save 5% vs buying separately)
Or grab the individual parts:
Quick spec
4L80E (1991-present):
- ~600 ft-lb stock capacity
- 4-pinion planetary
- Standard input shaft
- Found in HD GM trucks 2500/3500
4L85E (2002-present):
- ~750 ft-lb stock capacity
- 5-pinion planetary
- HD input shaft
- HD truck and Express van applications
RPO codes
- 4L80E: MT1
- 4L85E: MN8
- Read our GM trans serial decoder
What changed in 4L85E
- 5-pinion rear planetary (vs 4)
- Stronger output shaft
- Updated direct clutch pack (more frictions)
- HD intermediate band
- Read our 4L80E intermediate band
Parts that interchange
Direct swap:
- Solenoid pack
- External sensors
- Pan, filter, gaskets
- Most external parts
Don't interchange:
- Planetary gear sets
- Input/output shafts
- Some HD clutch pack components
- Read our best 4L80E rebuild kit
Applications
4L80E:
- 2500/3500 trucks (gas) 1991-2007
- Suburban HD, Express van
- Some HD passenger
4L85E:
- 2500/3500 HD trucks 2002+
- Heavier tow applications
- Express HD vans
Common failures (both)
- Direct clutch wear
- Read our 4L80E direct clutch HD upgrade
- Front pump seal
- Read our 4L80E pump bushing
- Solenoid pack wear
- Read our 4L80E shift solenoid replacement
Rebuild cost
- 4L80E DIY: $1,200-$2,000
- 4L85E DIY: $1,400-$2,300
- 4L80E shop: $2,500-$3,800
- 4L85E shop: $2,800-$4,200
- Read our 4L80E rebuild cost 2026
Which for your project
- Daily 4WD truck: 4L80E adequate
- HD tow over 12,000 lb: 4L85E preferred
- Race build: either with HD parts
- Read our 4L80E vs 6L80
Need 4L80E or 4L85E parts? Shop our 4L80E catalog. Rebuild kits, HD upgrades, complete solutions. Free shipping over $70.
Related: