Praedator

Feels like? Jack up all four wheels and find out where the disconnect is and what is turning and what is not. Old school knowledge here. Got to just find out where it's turning and where it's not when the problem occurs. Also could be a ground issue. There is a main ground usually on the frame by the driver's side door to ground the system. https://www.knowyourparts.com/technical-resources/hubs-bearings/automatic-locking-hubs/

I drive off road quite often with ruts and more. That air damn was coming off whether I ripped it off or took it off myself. Chose option number 2 and took it off myself. Best thing ever.

Not enough information to even start to help. What is it doing other than showing a light? Not engaging at all. Engaging 4WD LO but not 4WD HI or vice versa? Jack your truck up off the ground with all four wheels in the air. Engage 4WD, what spins and what doesn't? Noises? You get my point. Not really enough to go off of here. Sounds like you might just want someone to take a look at it if you can't put a little more effort into diagnosing the issue. Nothing against you or your skills. But you have to give us more to go on here.

Depends on where you live, climate, road needs salt etc.... Here in the south, I live near saltwater and I do a thorough cleaning behind my wheel well covers. My front are factory and my back are rough country plastic that I added to not have black fronts and white back wheel wells. Really protects the rock chips and other things I think would cause rust much sooner. Doesn't take much to spray behind the plastic ones in the back. The front factory ones are a little more difficult to rinse out behind them.

Rough country listened and we finally have a hidden winch mount for our trucks! https://www.roughcountry.com/gm-hidden-winch-mounting-plate-11004.html Ordering mine now.

George Carlin said it best Sent from my XT1710-02 using Tapatalk

That was my next move. Simply disable the lock altogether.

OK, Annoying thing is the tailgate locking function!!!! I know the reasoning behind it! But I have a hard toneau cover and it's locked! So my tailgate really isn't going anywhere. The problem is, I will get out and go to the back of the truck with the keys int he console or something and forget about the dang thing needing to be unlocked just to get something out real quick. Anyway to have the tailgate unlock with just the driver's side door unlocking and not "ALL" doors. 2018 GMC by the way

Just like my regular 4x4. No z71! Ordered skid plates that are metal and have used them quite a bit. But I have a manual 4x4 shifter on the floor. So I have low and high 4wd. Sent from my XT1710-02 using Tapatalk

Sorry I have to laugh at this! 1mpg? Try putting two 0's and a decimal point in front of it. Mine is completely stock other than adding slightly more aggressive stock size tires and taking off that stupid curb scraper plastic. I drove it for 6 months with it on. Took it off and no noticeable MPG decrease on the DIC that I've been able to tell. And I drive 26 miles mostly hwy one way to and from work everyday! It may help some. But it's an everyday truck, not a NASCAR that needs every inch of air flow diverted or else you're not going to make that last lap on the tank of gas. Keep it on if it's not in your way or you like the way it looks. I scraped it and tore the plastic going down my very first dirt road with some minor ruts. So off it came. Sent from my XT1710-02 using Tapatalk

Couple of screws he says! More like a thousand! Took mine off since new. But I'm on trails half the year hunting. I'd have ripped it off the first outing. Sent from my XT1710-02 using Tapatalk

I have factory 17" rims on my truck with a 2" front level. I prefer more rubber than the skinny rubbers!

I am lucky to live out in the sticks a little and have a lot of back county places to adventure to.

Self Isolation and doing some back country roads!

Behind glove box Sent from my XT1710-02 using Tapatalk