Allison MT643 4-Speed Transmission Question

Discussion in 'Class A / Diesel Pushers' started by brcompton, Dec 22, 2006.

  1. brcompton

    brcompton New Member

    I am considering purchasing an older RV with a CAT 3116 engine and a Allison MT643 transmission. It does not have an engine or exhaust break. Can this be added to my unit as an add on?
  2. dbarton291

    dbarton291 Senior Member

    Re: Allison MT643 4-Speed Transmission Question

    Yes it can. It's not cheap. You also have to wire in a switch in the lockup signal pressure tap on the transmission so an engine brake or exhaust brake is only active when the lockup clutch is on.

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