Hello, I am new at this hopefully I'm in the right spot. I have a 2005 GMC with 1000pk transmission. I've been too three different shops over $1,200 and still not fixed. It drives fine for the first maybe 15-20 minutes or more or less. And then you go to slow down it clunks and will not shift. And when you put it in park or move the shifter to neutral. It clunks and the driveshaft looks like moves back and forth. Turn the key off for a few seconds start it back up and it is fine until you drive it again for a little while then it acts up again. Any suggestions would be greatly appreciated thank you.
Transmission problem
- Thread starter buster4114
- Start date
Do you have a way to pull codes? If an Allison is doing weird things there is a very high probability it has codes for it, they are crazy smart.
This sounds like a job for a real Allison tech honestly. It will be cheaper in the long run. Where are you located?
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You might be surprised. I've got a cheap actron pocket scanner(9145 I think), and it WILL read tcm codes. I know most cheapy's won't, but actron seems to, and all the AZ's I've been to used actron. So you can try it, but if all you get is a p0700 and no other codes, then you need a better scanner.
I am located in Napoleon Ohio, the first shop I took it to. They said they did some testing on the valve body and everything tested okay so they took the valve body off and soaked it and put it back on charge me over $600. The second shop by took it to a pressure switch and wiring harness. Charge me around 400. The third shop I took it to put a neutral safety switch on it.
I had issues out of mine. Wouldn't shift right and throwing several codes. Range inhibit lights kept coming on. With a new one by the way. I bumped with my fist the tcm on the radiator connection and it quit instantly . This was 200 miles from home camping. Got it home and unplugged tcm and added dialectical grease never had a problem since. I would start with that.
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Soaking the vb. That’s a new one lol.
That’s how you fix stuff right? Windmill parts at it till it maybe goes lol. Some shops should be shutdown.
I dunno if Danville builds tranny’s or not but they are only 4 hrs or so from you. At least they aren’t retarded. Limitless is 10 hrs the opposite direction but I guarantee they will sort you out.
I've had a couple bigger allisons at work have similar issues due to output speed sensors or speed sensor wiring. It I have allison software to read them there.
You need to take it to a legit place though that can read the codes. Thought there were a few decent shops in Ohio I'll have to dig in my memory bank though..lol
You need to take it to a legit place though that can read the codes. Thought there were a few decent shops in Ohio I'll have to dig in my memory bank though..lol
I believe Crank it up diesel was up in your neck of the woods. His website seems behind but I'm pretty sure he's still pulling.
Sorry he replaced the harness assembly said there was a bad ground. And solenoid D shifts nice .A really nice guy.