My 2020 Trail Boss is in the shop right now. It's been in the shop for almost 2 weeks and the dealer is backed up so they haven't fully diagnosed it yet. Truck has 12, 615 miles on it. The tranny went all of a sudden. Left the house one morning, stopped a stoplight and when I took off from the light the check engine light came on and the truck started jerking. RPMs were up around 3800 and the transmission was slipping. Drove to the dealer and they checked the code, thinking at first it was a computer glitch or valve body issue. Because they were so backed up I decided to have them reset the code and drive it for a while to see if it would reoccur. 10 mins later the same thing happened. RPMs were around 4k at 70 mph and when I pulled away from a stop it would take 30 seconds or so for the tranny to engage enough to build up driving speed. Just posting for awareness and curious if anyone else has had problems with the 10 speed. I drive the truck about 6k miles a year and do not pull a trailer.
10 speed Transmission issues
- Thread starter mbrown
- Start date
Trail Brian
Active member
interesting and kinda scary...I've got 10 K approx and I have noticed when my tranny is cold first thing it hesitates (when dropped into drive from park) a slight bit before engaging almost like it's got low fluid... problem for me is I'm halfway down the Baja and won't be back to the Pac NW till mid January .... gulp...
Hopefully you don't have a problem. I don't mind paying top dollar for a truck, but I do expect better equipment and service for the price.
Have you had more issues since original post?
^ I'd imagine it's still in the shop.
I just joined this forum today, kinda to see what others are experiencing for trans issues. I have a '20 Trailboss 5.3 10speed, 20k miles. Trans (I think) just started on its way out this AM. Doing bout 80mph down the freeway, it started a few random driveline feeling bumps or jerks. Almost thought it was the wind hitting the truck first as it was blowing about 40mph headwind.
Within a minute, the ESC, parking brake, wrench and engine light all came on and it started flashing all the service warnings.
Drove truck another 10miles or so. It still shifts through all the gears, ok ish, but shifting at higher rpms. All but engine light goes out until you mash the skinny pedal again then the light show starts over.
It now vibrates at idle and a noticeable whine from what sounds like the trans when accelerating.
It's a company rig, set to go to the dealer this afternoon. Will keep y'all posted.
Truck has basically not worked a day in its life. Commuter rig with only a few thousand miles towing 3-6klbs.
I just joined this forum today, kinda to see what others are experiencing for trans issues. I have a '20 Trailboss 5.3 10speed, 20k miles. Trans (I think) just started on its way out this AM. Doing bout 80mph down the freeway, it started a few random driveline feeling bumps or jerks. Almost thought it was the wind hitting the truck first as it was blowing about 40mph headwind.
Within a minute, the ESC, parking brake, wrench and engine light all came on and it started flashing all the service warnings.
Drove truck another 10miles or so. It still shifts through all the gears, ok ish, but shifting at higher rpms. All but engine light goes out until you mash the skinny pedal again then the light show starts over.
It now vibrates at idle and a noticeable whine from what sounds like the trans when accelerating.
It's a company rig, set to go to the dealer this afternoon. Will keep y'all posted.
Truck has basically not worked a day in its life. Commuter rig with only a few thousand miles towing 3-6klbs.
Update:
2 collapsed lifters, dunno which ones or how many they're replacing yet, or if any other damage. But do know they're not on the shelf at the dealer and trying to source them.
Will be interesting to hear the whining noise disappear. Sure sounded like the pump in the trans...but what do I know.
2 collapsed lifters, dunno which ones or how many they're replacing yet, or if any other damage. But do know they're not on the shelf at the dealer and trying to source them.
Will be interesting to hear the whining noise disappear. Sure sounded like the pump in the trans...but what do I know.
1976jeffrey
New member
I had my transmission replaced at 25K with the same issues above, now at 53K I am having the same problems again with the new tranny.
1976jeffrey
New member
I had my transmission replaced at 25K with the same issues above, now at 53K I am having the same problems again with the new tranny.
1976jeffrey
New member
Most of what I have read it is the 5.3
The engine issues were one of the reasons I went with the 2.7ho, I know a couple Chevy mechanics and they told me they have way fewer issues with the 2.7’s. They used to tell people to change the oil more frequently than required and use only synthetic oil and that would prevent lifter issues but whatever’s going on now is completely different and most likely out of spec parts.
My 2020 5.3l 10 speed Trail Boss is going in the shop tomorrow. Noticeable whine from the engine/transmission. No warning lights or hard shifting, just a whine. Dealer/service rep. said it is the 10 speed transmission, just from listening to it. I can sit at an idle and rev the engine. The whine will rise and fall with the engine RPMs. Started at 36,500ish miles. No problems with truck up until now. I'm pretty easy on this truck. No off road, but tows a Bass Boat, may be 3500 - 4000lbs.
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