Engineerguy

I have 40,000 miles but I want to see if I can get some idea what's going on with my transmission, I can't afford to do anything so if this is something that can get fixed under warranty I want to do that, but if I'm going to go in, find out it's not going to be a warranty repair and then get charged for diagnosis - that's something I need to avoid because I'm between jobs.

I'm an engineer and I've done a lot of work, if it came down to it I'd probably park the truck for the winter and do a trans rebuild or replacement myself in the spring or summer. I have a general understanding of how transmissions work, but what I've worked on is of the 1955 vintage. Point being, in providing an answer there is no need to hold back on being technical because that's the kind of answer I'm looking for.

The exact symptom is this... The truck will pop into neutral if it is in drive when it should be making the 1-2 shift at 1000 RPM, it won't engage second until 1500 RPM. It similarly won't downshift from 2 to 1 during deceleration. In order to be driven, it needs to be in Manual mode in first gear from a stop, once above 1500 RPM it can be shifted to second in manual or shifted to drive, beyond that point it will operate normally. It will lurch forward a bit when you engage first gear in manual too.

If I recall my automatic transmission fundamentals correctly, the automatic trans will basicly engage both first and second gear while it's transitioning, and it seems as though it is doing this incorrectly.

I've done a fluid and filter change twice, and it helped somewhat... The fluid change was done after the problem started within a day's use for commuting, it was parked after until the fluid change, but during the drive it seemed to get worse. I did the second fluid change in hopes that maybe if it was a fluid problem, fluid that remained in the system but hadn't been changed might be further removed or diluted with new clean fluid.

I've used the truck for trailer pulling. On a recent trip (3 hour drive) I had a problem in the last 15 minutes of driving where the trans locked in 3rd gear. I checked the trans temp and it read as 212 degrees F. The next day after it cooled down it seemed okay, but I didn't use it much more than 2 or 3 days before the day when I decided a fluid change was needed.

So my questions:
Am I correct in understanding my warranty that this would be covered under the 100,000 mile powertrain warranty as opposed to the 36,000 mile bumper to bumper for which I'd be out of the warranty period?
Do I need to be concerned that a warranty claim might be denied because of the trailer load being excessive (shouldn't be, I got the trailer package and it's a single axle enclosed trailer with furniture, don't think I exceeded any load) OR because of the fluid change?
Any idea what component within the trans might have failed?
Could it still be fluid and would it be worth another fluid and filter change?

nauticstar87

Should be covered under the 100,000mile warranty seeing how it is a drivetrain problem. Shouldn't be denied for excessive load. I honestly wouldn't say anything about it. The older electronic trans had solenoids that could cause a no shift, I'm not sure on these newer ones. I would try the dealer and see what they can do. My truck had 65000 miles on it when I took it in for a trans issue, they fixed it under warranty, plus gave me a loaner.

Chevrolet Customer Service

Hi Engineerguy,

We’d like to look further into the complications that you have been experiencing. Please send us a private message with your VIN and more information and we can assist with your warranty questions. We look forward to hearing from you soon!

Kristen A.
Chevrolet Customer Care

Moonlighter625

Sounds like the Transmission control module going bad. I hate all this new crap, and yes should be covered under the 5 year 100,000 mile drive train warranty.

Engineerguy

Turns out the issue was the low/reverse clutch was roasted. It's been repaired now under warranty.

nauticstar87

Thanks for getting back to us and letting us know. Surprised it was roasted for being under 100k miles.