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allison 6 speed

  1. Transmission Shop
    Hey All. So I've been having some issues w/ my 09 GMC 2500 HD Duramax that just rolled 102xxx miles. A few weeks ago I was driving my truck home, came to a rolling stop, proceeded to drive and it wouldn't come out of first gear, and the money light came on simultaneously. I limped it to the...
  2. Transmission Shop
    I was leaving Taco Bell on Friday, and when I shifted from park to drive, there was a delay, clunk, then immediately “GEAR 4” is displayed on my monitor. I pulled over and ran codes, and saw TCM. I tried clearing them and shut the truck off. Started back up, drove maybe 2ft and then clunk! 4th...
  3. Transmission Shop
    The truck. Medium duty 2005 Chevy c4500 Transmission was sold out of it What should I put back 5 speed allison?? 6 speed Allison ?? will i be able to communicate and use 6 gears or does the same rule apply to medium duty what digit tells me what trans belongs 1000/2000 any help greatly...
  4. 07.5-10 LMM Duramax Powertrain
    A couple weeks ago I went to take off in my 2009 lmm and realized I had no forward gears and it shifted very hard into reverse so I thought it was a tcm sure enough after getting a new one it shifts smoothly into reverse and backs up fine but still has no forward gears when I put it into drive...
  5. Transmission Shop
    Had this 02 since it was new. It’s got 96,000 miles on it. Mostly pulling hard with hay out of the hay field . Got hot while pulling a 30’ flatbed with 70 hp tractor on it on the highway . Was jerking and it was stuck in high gear . Didn’t check tranny temp . Mechanic reset it and changed...
  6. Gauges, Electronics and Wiring.
    Hopefully this helps somebody out there experiencing this issue: Gear indicator not working, or working intermittently. No reverse lights, doors won't unlock in park. Truck drives fine but later on did experience some more issues (Banks Brake not working, Tow/Haul mode not downshifting). I...
  7. Transmission Shop
    Truck is throwing codes P0700, P0757 and P0847 after ripping her down the road. I have 120xxxmiles on my LBZ, deleted and tuned truck last month with MotorOps tunes sitting on 35" tires. truck wouldn't shift after check engine popped up. came to a stop, cleared codes and tried again. Truck...
  8. Transmission Shop
    First of all, since I am new, I should introduce myself. I have been lurking for a while, but just registered. You guys have a great site! My truck is a 2006 regular cab 4x4 with the 6 speed Allison. About 3 weeks ago, my tranny would erratically go into limp home mode, always on a cold start...
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