newdude

Ya upper arms or sway bar links bad again. Lots of level in the front there. Things hold up ok at 2 inch level, but beyond that, forget it.

I tow quite often. I never feel inconvenienced and its added safety for my hitches.

Take the hitch out. Problem solved. Many states its technically illegal to leave it in the receiver anyway.

From the dealer side of things aka., issues we see (in NY): - DEF heater. Primarily the reservoir heater in the tank. - NOX sensors. Both of them. - Head gaskets. Mainly 2011-2013 but those are the same LML engine so I added it to the list. We did do them on 2 2015's. - Coolant leaks. Mainly the rear engine cover housing. - Brakes and parking brake. In NY especially as the winter season just seizes the caliper slides and parking brake and everything gets replaced.

I changed my original response to OP as I noticed he had an SLT Yukon. Is yours push button or keyed?

Yes. As long as you are push button start.

That is a factory pickup box mount. Pickup box mounts direct to it with a rubber insulator between the box and the frame. Service body might not use all the factory mounting points. I'd be checking with whoever installed the box, or the box manufacturer to see what the mounting locations are for that specific service body.

2020 DC standard box is 240.45". Up from 230".

It was so hard it sent the driveshaft through the bed floor and took the rear of the transfer case with it...

Trans. Pan drop and filter change. Dropping it twice will change out probably 80-90% of the old fluid. Flushes get all of the fluid in one shot sure, but flushes are NOT recommended by GM for engine and trans. Fuel injection service. If you read up on the testing BG did on a Taurus SHO, they had actual dyno results at purchase, at 30k miles, and then after their service. They picked back up like 20-30hp that they lost due to carbon build up. SHO is a DI motor. That said, unless they are using an actual DI engine service kit? Not worth it. If they are using the standard fuel injection service kit, they are wasting your money and time.

Denali comes standard with U1D In Vehicle Trailering App: PTT would have added the sensors. Otherwise, the truck is ready for them because of U1D which gets the module. Look behind your rear license plate. There should be a little black box on the right side of the opening. If that's there, 84338125 is the TPMS trailer kit. 2 sensors per package. Typically the sensors are left loose in the truck by the technician at PDI if ordered with PTT. Where may vary. Glove box, (upper or lower), under the rear seat storage, center console, center under seat storage with bench seats, etc.

Do you have any oil consumption?

Old 4.3 was Gen 1 350 based. 350 minus two cylinders. The "Vortec" 4.3.

Seen some get cams at work. If the lifter gets stuck right it scores the piss out of the cam, especially if the lifter spins in the retainer. Roller ain't rolling no more if that happens.

Part of the interal wiring harness on the 8L90 8 speed. 24297369 is the most current #. Retails for $95.06. I show coverage ability for factory powertrain and factory emissions for that if its the cause of your issue.