I have a 2018 GMC duramax 6.6
Allison 1000 transmission
Truck had been deleted.
I bought the truck a year ago cash off market place
before i purchased the truck
Truck went into the dealership for maintenance
Mechanic put Gas in the truck .
Long story short truck has a brand new motor with 30k miles. Truck all together has 158k miles
When I bought it there was a code on the dash that I could not get cleared.
Would go from two screens
“Emission system”& “158 mph max speed”
This is the only thing I could get my truck to read. I was unable to get into my dash at all
Truck had no performance issues at the time
No slipping no lights in dash
not any noticable issues
I took it to the diesel shop that did the delete
They couldn’t figure it out
I took it to another diesel shop that was highly recommended
They couldn’t figure it out.
For the first 6 months besides the error codes I had zero performance issues.
Truck was at the shop and it was going to be like a 5 day weekend so I went and picked it up and drove it home (about a hour drive)
Then
Drove the truck to a pub about 40 mins away
and then back home so a good 2.5 hours total after leaving the shop.
Next morning I got into the truck
Truck started no problems i put it in reverse and nothing.
Truck has not moved sense. It will not go into drive or reverse
I have pushed it back to just to make sure it wasnt locked up rearend.
Codes are always throwing something different
I have changed just about every sensor
Ran over the wiring harness serveal Times dont see a problem.
I really thought it was going to come down to being a issue with my TCM but I tested it yesterday
By tested I put mine into the exact same truck and it worked perfectly.
(I’ve had 3 different mechanics come out and after 20-30 mins of looking at it ive been told it’s my TCM) it’s not!!!
Last month I took the ECM out and it sat out for a week or so. When I put it back in the codes mentioned above went away. I have started it up and ran for long periods of time several times message has not come back on
Truck still will not move.
You can hear it shifting into gears
Yesterday
We drained the transmission fluid (lower half)
and added new fluid
It was about 4 quarts low
The transmission harness connection was wet. We cleaned it (similar video in comments)
Reset the TCM
I’m at the point where I believe maybe it’s the torque converter. But just trying to do as much research as I can first.
There are Zero codes reading as ofyesterday
Allison 1000 transmission
Truck had been deleted.
I bought the truck a year ago cash off market place
before i purchased the truck
Truck went into the dealership for maintenance
Mechanic put Gas in the truck .
Long story short truck has a brand new motor with 30k miles. Truck all together has 158k miles
When I bought it there was a code on the dash that I could not get cleared.
Would go from two screens
“Emission system”& “158 mph max speed”
This is the only thing I could get my truck to read. I was unable to get into my dash at all
Truck had no performance issues at the time
No slipping no lights in dash
not any noticable issues
I took it to the diesel shop that did the delete
They couldn’t figure it out
I took it to another diesel shop that was highly recommended
They couldn’t figure it out.
For the first 6 months besides the error codes I had zero performance issues.
Truck was at the shop and it was going to be like a 5 day weekend so I went and picked it up and drove it home (about a hour drive)
Then
Drove the truck to a pub about 40 mins away
and then back home so a good 2.5 hours total after leaving the shop.
Next morning I got into the truck
Truck started no problems i put it in reverse and nothing.
Truck has not moved sense. It will not go into drive or reverse
I have pushed it back to just to make sure it wasnt locked up rearend.
Codes are always throwing something different
I have changed just about every sensor
Ran over the wiring harness serveal Times dont see a problem.
I really thought it was going to come down to being a issue with my TCM but I tested it yesterday
By tested I put mine into the exact same truck and it worked perfectly.
(I’ve had 3 different mechanics come out and after 20-30 mins of looking at it ive been told it’s my TCM) it’s not!!!
Last month I took the ECM out and it sat out for a week or so. When I put it back in the codes mentioned above went away. I have started it up and ran for long periods of time several times message has not come back on
Truck still will not move.
You can hear it shifting into gears
Yesterday
We drained the transmission fluid (lower half)
and added new fluid
It was about 4 quarts low
The transmission harness connection was wet. We cleaned it (similar video in comments)
Reset the TCM
I’m at the point where I believe maybe it’s the torque converter. But just trying to do as much research as I can first.
There are Zero codes reading as ofyesterday
