Big, Heavy, Strong MT643

The MT-640 and 643 Allison Transmission is used in heavy vehicles that require that extra punch not available on other units. It is used in buses, trucks and other heavy vehicles.

The rebuild kit is available as an Overhaul Kit, Banner Kit and Master Kit. Friction and Steel Plates can be purchased separately. The Overhaul kit comes with the Armstrong gasket and Vespel Rings.

The filter pictured below is the standard filter for this unit (paper with large grommet hole). There is also a paper filter with small grommet hole and the stainless steel wire mesh for 5" pan used with auxiliary filter. There is also the spin on cartridge, governor and center support filters.

Bushing are available as follows:

- Bushing Kit
- Pump
- Center Support
- Center Sun Gear
- Front Planet Carrier
- Low Planetary Carrier
- Rear Output Shaft (Replaces Bearing)

The pump bushing comes in 2.443, 2.530, 2.580" inches in overall diameter. Always take some time to check the external cooler to make sure it is functioning properly as it is a critical part for the life of the unit.