NWI Denali

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.

That is a really good looking truck

$400

What you describe sounds like tire howl

These LT engines seems to idle rough. I think a lot of it has to do with how low of an rpm they idle at. They almost shake and stumble like a cammed muscle car. I don't know if it's for fuel economy standards or what.

Do you have the 8 speed? If so, it's the tcc shudder. Dealer will do a 20qt flush for you under warranty that should fix the issue. Does it feel like running over rumble strips?

5 yrs ago, the tire selection for 22s was terrible. Now with how many Tahoes, ram limiteds, F150 limiteds, denali's and high countries they sell, there are a ton more options. Good all terrain options too. 275/50 is an oddball size. No idea why GM changed from the 285/45 they used for years. My guess is the get the extra inch of sidewall from 32 to 33. My truck is a K2, and I just put these Cooper Rugged Treks on stock size 285/45. Cooper lists it at 32.36". I absolutely love these tires, I cannot believe how quiet they are for how aggressive of a tread pattern. They have tons of siping for snow too.

Do you know if it's ever been changed? I would do a pan drop and put the new and revised mobil1 atf in and new filter. Then I'd do it probably every 50k from there on out

Do you know if it's ever been changed? I would do a pan drop and put the new and revised mobil1 atf in and new filter. Then I'd do it probably every 50k from there on out

Do you know if it's ever been changed? I would do a pan drop and put the new and revised mobil1 atf in and new filter. Then I'd do it probably every 50k from there on out

Do you know if it's ever been changed? I would do a pan drop and put the new and revised mobil1 atf in and new filter. Then I'd do it probably every 50k from there on out

If it makes you sleep better at night that's fine, but that is Overkill and a complete waste of money.

Well, I finally have a resolution. Had my dealer diagnose it and they actually found the harness rubbed through on the frame near the rear wheel well. Looks like there's a mounting bracket for the brake lines is what did it. They repaired the harness and all good to go now. Thanks to all for the help troubleshooting.

That is the trans shuddering. Since you like the truck, I would have the dealer do the trans flush and see if that fixes it. If it doesn't, then return the truck to Carmax.

The Chevy shake and transmission shudder are 2 different things....

Well, I cleaned that ground and that still didn't do it either. I really am out of ideas at this point. See if the dealer can find anything Wednesday.