What did you do to your 21+ T1XX today?

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RWM +1
Supporting Member
Mar 26, 2022
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SW Florida
I bought the '17 Yukon (5.3 6 speed) used and noticed AFM right away. Cruising along, especially at lower speeds, a little throttle tip in and feels and sounds like it's lugging. Blackbear tune and I was thrilled, tuned off the AFM, fixed the weirdness with the trans shift points, night and day difference in drivability. Corsa sounded good at all times instead of the helicopter sound during lugging. Very little to no drone from that exhaust though, regardless, which was impressive.

I was optimistic with the '22 Tahoe (5.3 10 speed) DFM. Didn't notice it at all first 7,000 miles or so. Now, same thing as AFM, lugging. The miles, the time, the first oil change, the colder weather, a stack up of all these variables but now it's here on my Tahoe and very noticeable. Blackbear seems to be a no-go, checked in with them earlier this week. Range isn't saying no, but if blackbear can't is it realistic they can? I tried 89 octane and noticed a slight improvement, running a first tank of 93 now for the heck of it incase the cylinders that are firing when DFM kicks in will misfire less with the higher octane (grasping at straws). Could cause the opposite problem and have DFM kick in even more with the higher octane though. We'll see if that helps. Also have a bottle of the ACDelco injector cleaner coming, the one recommended in the manual. Can't imagine I have buildup already, gas I run isn't top tier but it's a newer and very busy gas station.

Last resort is running in L9 as it stops DFM (and auto stop/start which is nice), just don't love losing a gear as a "solution" and I'm not sure I like what the transmission is doing in L9. We'll see, that might be what I end up sticking with if the 93 octane doesn't do the trick.

My process:

Always use highest octane (92 or 93) Shell or Mobile
Start Yukon
Already have auto on/off disabled with module added
Let cold start end
Wait about 5 minutes of driving
Change to Sport Mode
Change to L9

So maybe with my above process im good.

On the fence between the pedal commander or a Corsa CAI for my next item.


Full Access Member
Jun 28, 2021
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I would get wider tires that protect those wheels ! Bridgstones don't look very beefyMy Goodyear trailbosses have more sidewall. Is that just from parking?
I really wanted the AT4 because the of wheel/tire package, but the wife said it looked to manly....

Both times it has been on street curbs, to be fair at the last incident, the curb is very high and its a tight right-hand turn.


Aug 16, 2021
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I find having a d-ring on the back of my vehicles comes in handy and didn’t love the look without the hitch cover on the Tahoe. Started messing around with options and came up with this. Pretty happy with how it turned out. Maybe someday there will be an oem in-use option that will expose the trailer electrical connection and chain connection points that looks clean, but until then this should work for the d-ring at least.View attachment 388334View attachment 388335
What material did you use to line the opening once you cut out the rectangle? I was considering making a similar cut on my cover, and I really like how you finished yours.


Full Access Member
Nov 22, 2019
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What material did you use to line the opening once you cut out the rectangle? I was considering making a similar cut on my cover, and I really like how you finished yours.
Thanks! I cut it first without and trashed my first hitch cover, as careful as I was with the Dremel it just wasn’t clean enough looking. Tracked this down in black and ordered another hitch cover.


Full Access Member
Aug 21, 2021
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North TX
Took advantage of the low workload at Discount Tire……Swapped the tires and TPMS over to the new Gloss Black MultiSpoke wheels for my 23 Premier….with red center caps.

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