asilverblazer

If there is no more adjustment in the upper control arm adjusting bolts, something is likely bent. Either the upper control arm, or the mounting points, hopefully the upper control arm. Also check "z-trim" height. If the front end is riding low it will cause excessive camber too.

Gooseneck hitch, needs the removable ball. There is lever in the fender well you pull to allow the ball to slip into the opening.

Find someone with a Chevy and swap them? Or are we past offering solutions now...

Welding up the differential is something you do on a 20 year old mud truck, not a 4 year old daily driver. You will regret it. Drivability will suffer as noted above, plus, whatever you are doing with 35" tires that warrants a locked front axle is going to result in other far more significant failures. If your funds can't afford a proper locker, then they won't support the magnitude of repairs you will encounter either.

I could never imagine going back to a a 2wd truck. Better to have it and not need it than...

Rear brakes condition, including the parking brake?

Upstream O2 sensors control how the engine runs. The downstream O2 sensors determine condition of catalyst. The upstream sensor is controlling the fuel trims. The downstream may eventually throw a catalyst system efficiency code, but nothing related to drivability. Cylinders 1 and 4 are on different banks so fuel trim of bank 1 causing misfires on bank 2 would be odd. I would also confirm that the P0300 is in fact described as random, sometimes it is not described as 'random' but as a confirmation that misfires are happening (in conjuction with P0301 and P0304 in your case). This might rule out or confirm the misfires is happening ONLY on cylinders 1 and 4 or MOSTLY on cylinders 1 and 4. The ONLY unique items to check on those cylinders would be plugs, wires, cap, valves, compression. For a mostly condition that opens the amount of items to check up further to include injectors, vacuum leaks, etc. In summary, PCM's don't get confused so I think you need to keep digging elsewhere. Try disconnecting the battery for a while to reset the PCM, might give you a warm fuzzy feeling about it.

I wonder how much of this is driven by dealers building up stock in preparation for the potential (and occurrence of) the strike? Plus there have been a lot more incentives on the new trucks of late. My crystal ball says that will be the best quarter for the year.

Had them getting in my GMT900, never did figure out how though. Lots of poison outside around the house and driveway seemed to do the trick. Nothing like having a mouse run across your foot while driving down the highway will cause quite interesting diving maneuvers.

Torque converter clutch solenoid? Try lightly pressing the brake pedal (only enough to illuminate the brake lights) when the noise starts, This will electronically tell the TCC solenoid to unlock. Just got through replacing this part on another truck that exhibited similar symptoms. The solenoid was worn in such a way that it would not lock the converter like it should and would instead cycle between engaged and not (very rapidly), making a rumbling noise. That is why turning it 'off' or unlocking it with the brake pedal would make the noise go away.

Bad fuel pressure regulator = extended warm cranking times.

Don'y forget about vent tubes, front axle, transfer case, rear differential. Front and rear diff vents are right on top of the frame rails, going any deeper risks water entering the diffs and contaminating them. Some even feel the same about wheel bearings, basically hub depth.

I had trouble with them getting in my 2007, nothing will quite cause a scene driving down the highway like a mouse running across the floorboard. They made nests in my glove box, under the rear seat, etc. had babies in there too. Never could figure out how they were getting in. I resorted to lots of poison around the house.

Pulling the fuse usually disables electronic devices. I don't know how to take apart the thing, but usually there is a plug in the back that could be unhooked to. oooh, I'm scared now, don't sue me...

Suburban third row isn't bad. Tahoe third row awful.