My transmission shifts too soon and bangs into gear at about 8 miles an hour
How many miles are on it? You might still be within the 5yr./60k powertrain warranty.
7900 miles
If it’s under warranty (appears it might be, depending on when it went into service) I’d definitely take it in to the dealer. If it’s the 8 speed automatic (I’m not sure exactly what years the 8 speed was offered), there’s a technical service bulletin out. I think they replace the transmission fluid with some variant of Mobil 1. The dealer might have a programming update too.
Thanks for the reply. I do have an extended warranty and believe it or not now I keep getting a message to service trailer brake system and I haven’t towed anything.
Yes, Tuesday morning drop it off at your Chevy Dealership.
But I am curious, how do you have less than 8000 miles on a five year old truck?
Oops 79,656
That is why it is banging off the shift. The truck is in the “trailer/haul” shift mode. That changes how the transmission shifts. You don’t have a transmission problem, you have a trailer brake system problem.
This is what happens when you don’t tell the whole story to people fixing your car or truck. It took the 3rd post for this to come out. Be sure to tell the service writer at the shop all the information even if you think it irrelevant.
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I thought I corrected that.
You corrected the mileage in your 4th post but didn’t tell us about the trailer brake warning until your 3rd post.
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Really dude, I had a mother in law that would nit pick like that. And not one suggestion about the problem. I thought I left FB two years ago.
Don’t be so sensitive. It takes information to receive good help , just like going to a Doctor. You have an Extended Warranty so use it and hope it is not as worthless as most of them are . The trailer warning means you have a serious problem that is not a do it yourself item unless you are a well versed mechanic.
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What Mustangman was saying, is that he believes the hard shifting is related to the trailer brake controller issue, and that the trans is possibly in tow mode due to the brake controller fault. If your trans is shifting early like you originally stated, I don’t think it’s in tow mode. Tow/haul usually extends gears to shift later. Still, the trailer brake issue might be part of the trans shifting problem since everything on vehicles is computer controlled these days.
There is some info on the factory installed trailer brake controller on the web. Appears to be a common complaint and may not be that difficult to resolve.
Did you ever say if the trans was the six speed or eight speed auto? 8 speed had a lot of issues.
Personally, here’s what I’d do. I’d see if I couldn’t sort the trailer brake issue out myself by researching it a bit on the web. I’ve seen posts of people fixing that by cleaning terminal connections or replacing a pretty cheap module. If it helps with the trans shifting, sweet! If not, I’d bite the bullet and see if that warranty pays for itself.
I didn’t start the nit-picking, you did.
Apparently missed these two…
and
You DO know we aren’t PAID to do this, right? I’m out.
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