re: Chevrolet unveils updated 2025 Tahoe and Suburban

Anecdotal, so take it for what it’s worth, but my brother has a ‘21 Tahoe that’s doing the same thing. He said the dealership says they’re instructed to replace the gear oil in the rear end twice, then if it still makes the noise, replace the rear end. They just tried with the oil for the second time and it didn’t help. So it’s going to the shop.

He used to be a mechanic at the same dealership. According to him, and I think this is common knowledge now, on the 5.3’s, you have a 50/50 chance that the lifter spring on the #6 cylinder gets weak and fails around the 75k mile mark. When it goes, you get a bent valve and may need a replacement piston depending on severity.

He also said you have the same odds of a solenoid going out in the transmission and losing 2nd and 3rd.

He said he refuses to have a GM that’s out of warranty.