Author Topic: Allison Transmission Discussion Forum  (Read 3345 times)

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Offline Ken Carpenter

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Allison Transmission Discussion Forum
« on: November 17, 2011, 06:12:41 PM »
Allison Transmission - Allison transmissions through the years:
http://autos.groups.yahoo.com/group/AllisonTransmission/

2005 Winnebago Journey 39K, C7 350HP
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Offline roysboat

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Re: Allison Transmission Discussion Forum
« Reply #1 on: December 21, 2011, 07:01:37 AM »
Have 1990 beaver contessa with MT643 auto trans,  trouble auto downshifting on hills. any ideas? Roy

Offline Brett Wolfe

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Re: Allison Transmission Discussion Forum
« Reply #2 on: December 21, 2011, 07:21:30 AM »
Welcome the the Cat RV Club forum.

Your transmission is hydraulically controlled, so is different than the newer 3000 and 4000 series transmissions which are electronic.

Check the linkage from throttle  positioner on the engine to the transmission. If the end comes off or linkage is mis-adjusted it can cause improper/incorrect downshifts.

Allison can help you if it is not the linkage: Allison help line 800 252 5283
« Last Edit: December 22, 2011, 04:52:23 PM by Brett Wolfe »

Offline roysboat

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Re: Allison Transmission Discussion Forum
« Reply #3 on: December 22, 2011, 04:43:55 PM »
Thanks Brett, am looking into it...regards Roy