NWI Denali

So if I'm understanding this right, all 8 speeds '15-'18 should have the 2 piece harness from the factory, unless it was previously replaced during the time period a few yrs back when GM was using the 1 piece replacement harness?

Is there any way to tell if you have the 4way or 10way connector?

I am running p-rated Cooper Rugged Treks which are similar to the duratracs. Seemed the outsides were wearing a little faster during the first 7k miles so I have since bumped them up to 38

2017 Had the "recall" refresh done Oct 2021. Just started getting the hard pedal/loss of power assist at parking lot crawl a month ago. Dealer replaced pump and new belt under warranty. They seemed pretty aware of it. Service writer said he has one tech who has done 200+ of them. Keep in mind this is a small town dealer too lol.

Damn! You were well due!

I was gonna say grounds too. Check grounds, battery, and alternator. Also check for any DTCs

The mileage some of you get out of stock brakes is incredible. What makes our trucks' oem brakes so good? I had a 2013 f150 and the brakes were absolute ******. Warped and shot at 20k

Don't need brakes just yet. I'm at 60k. Just was trying to get wome ideas. I've seen a lot of guys post on here that they get 100k on their stock brakes

What's everyone running for brakes? Is OEM AC Delco the best? Or Powerstop with the extreme duty towing pads? Ebc?

275/65 is the same width as 275/60 Do you mean diameter?

Corporate average across the whole line of vehicles. Not for every vehicle. And if manufacturers don't make the number, I'm sure all it will mean is they will merely have to pay fines etc. And guess who will pay those fines? It will be passed down to the consumers in gas guzzler tax etc lol

I have not seen where exactly they repaired the harness, just going off of their word. They said where it runs along the frame rail near the driver rear wheel well. Are you getting the service trailer brakes message? Have you replaced the other 3 parts like I did as well?

Awesome help and diagnosis. Good job, forum!

^agreed. It's a wash- get an inflated value for your current truck and pay an inflated value for its replacement.

Well trade in and retail are 2 completely different things. I would think maybe like 30k trade in, 35k retail.

There are magneride bypass kits if you want to run regular shocks with no diagnostic lights on. Check out Xineering Bypass kit is like 300 bucks

Mileage loss is kinda hard to tell, because I got the tires right when we started switching over to winter gas. But they are heavier, 50 lbs vs my oem Bridgestones that were 40 lbs. I would say I lost 1.5 mpg. They howl a little bit from 40-55mph. But then from 60-80, they actually quiet down and are only marginally louder than stock. It's mind boggling how they can run so quiet on the freeway with how aggressive the lugs are. I would buy them again 100%, and I am one who wouldn't be able to tolerate loud mud tires like Trail Grapplers.

They are fine in the rain. Having noticed anything squirrely. They did really good in the snow too I was happy with that. They have pretty good siping. I was torn between the g2's and these cooper's. I wanted the 285/50s for the extra inch. But the tread pattern on these coopers is way more aggressive and looks better. I didn't feel like the extra 100 dollars a tire was worth it for the g2s

Do you have the scroll wheel fully open?

Yes.

I think you did pretty good for 24k

It actually says "check trailer wiring?" Or does it say "service trailer brake system?"

OP, how many trans fluid changes? At what mileage did you replace shocks?

6 speed or 8speed?

You have 2 different, unrelated issues going on. What you have while driving is 100% the trans shudder. There is a TSB for a fluid exchange with 20qts of the new Mobil 1 ATF. This would be covered under your powertrain warranty. However, you being at 63k miles is a grey area... if you have a good dealer, I'm sure they could get it goodwilled for you through GM. The stumbling at idle is a completely different issue on its own. You already did plugs and wires. Only other thing I could think of is to clean the mass airflow sensor.