grassrootsinab
New member
Hi everyone,
New to the forum as I just picked up my 2026 Sierra 1500 AT4 on Saturday. Love the truck except as I drove it on the weekend, it kept making a "clunk"/"thud" on the down shift; sometimes at 5th to 4th or more likely 3rd to 2nd. Did a little research and seems that electronic programming and "learn" mode needs to be reset. Doesn't give a whole lot of confidence with the truck had 86 km (53 miles) on delivery and now has 325 km (200 miles). Dealer is going to make good this week with a service look and a loaner. I'm hopeful that it is just the "learning" process and not the solenoid or valves.
Anyone else experience this out of the gate that can give me some reassurance that it can and will be fixed. Had a 2018 Denali with the 5.3 (fantastic mileage for a gas) that I trade on the 3.0 Duramax. Really liking the torque but this shifting thing has me a little rattled!
Thanks!
JC
New to the forum as I just picked up my 2026 Sierra 1500 AT4 on Saturday. Love the truck except as I drove it on the weekend, it kept making a "clunk"/"thud" on the down shift; sometimes at 5th to 4th or more likely 3rd to 2nd. Did a little research and seems that electronic programming and "learn" mode needs to be reset. Doesn't give a whole lot of confidence with the truck had 86 km (53 miles) on delivery and now has 325 km (200 miles). Dealer is going to make good this week with a service look and a loaner. I'm hopeful that it is just the "learning" process and not the solenoid or valves.
Anyone else experience this out of the gate that can give me some reassurance that it can and will be fixed. Had a 2018 Denali with the 5.3 (fantastic mileage for a gas) that I trade on the 3.0 Duramax. Really liking the torque but this shifting thing has me a little rattled!
Thanks!
JC
