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Allison Question

2771 Views 5 Replies 5 Participants Last post by  Diesel Nut
I am planning a transmission swap in my 1998 H1. The donor transmission is going to be an Allison.
I was wondering from anyone who has experience towing how is the 6 speed compared to the 5 speed?

Right now I am having a hard time finding a 6 speed, but I have found some 5 speeds for $900 to $1000. I know if I can find a used 6 speed it would be at least double.

Would that extra overdrive on the 6 speed benifit my truck?
Would the extra money that I would pay be worth it?

My hummer is over 10,000 lbs and has very poor aerodynamics. But I guess anyone towing a large 5th wheel is also heavy with limited aerodynamics.
Thanks for any help,
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I'm not sure i would be too excited over a Alison for 900-1000. those are the trannys that guys like us abuse for 35,598 miles and switch to ATS or Suncoast... Like Travels said, this tranny will work harder than a stock application due to the larger tires, and you need to be conscious of gear ratio for top end speeds and towing ability. The (stock) transmission is the one of the weakest points of the HD drivetrain, and if you plan on being rough on your H2 without problems, get the suncoast or ATS right off the bat. NOTHING is worse than a smoked tranny on the side of the interstate. and historically, $900 wont buy a "mint" 700R4 + xfer case.... so, food for thought... its a lot easier to do something right the first time... check these guys out!
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