Suburban Duramax

I just bought a brand new 2021 suburban and just put up 3000 miles on it. I realized when I’m driving over 75MPH the wheel start to have a big vibration on the wheel even on my drivers seat.
second problem: so I’ve learned before first 500-1000 miles you don’t go over 55MPH and you baby drive it which I did. Now when I’m driving on a low RPM (1500) the transmission between 3rd and 4th gear shift has a crazy push or jump.
Did I buy a default suburban or something?
can someone help me out here please?
thank you. Greatly appreciated

oilcanhenry

Yeah, breaking in a new vehicle properly is important. Back in the day, they'd come with low detergent motor oil to seat the rings properly, but these days they come with whatever oil the manufacturer says it should have. I commend you for that! Most people just drive a new vehicle like mad, which isn't good at all. I think you can taking up past 55 MPH, just go easy on the throttle.

However, Chevrolet gave you a warranty, so I'd take it to the dealership and let the pro's repair it, as you paid for that warranty when you bought your Chevrolet.

73shark

Welcome to the forum. Be sure to visit there Suburban section of the forum.