AFM

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Mike2012yukonXl

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Hi y’all .. is it good to delete my AFM? Does it hurt anything and I guess I have to take it to a dealership to do it.
2012 Gmc Yukon xl 5.3 . Oh one more thing is the 6 speed transmission known to last and what can I do to it to make it last longer ? 143,000 miles on the Yukon. Thank y’all!
 

Charlie207

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Transmission: The low-hanging fruit move would be to drop the transmission pan, install a new filter, and add new fluid. The better move would be to proactively replace the torque converter with a billet-backed TQ to head off the common problem with the factory JMBX converters warping, which causes hot-spots, and leads to clutch/friction material wearing off, which circulates through the tiny passages of the transmission. This can lead to issues. Additionally, the factory transmission tuning isn't optimized, which can also cause longevity issues.

Engine: The AFM/DoD system is a known issue, and many folks opt to either have it physically removed with an AFM delete kit, or simply have it turned off with an ECU tune.

You can optimize the engine and transmission tunes with an aftermarket solutions (ex. BlackBear Performance) which costs more, but gives you the best case results without tearing in the engine/transmission. (best)

A popular & cheaper option is to buy one of those Range OBD dongles that tricks the ECU into staying in V8 mode full-time. (meh)

There is a tuning service where you send in your physical ECU, and they will permanently disable the AFM programming. (better)

You can also disable the AFM system by shifting into Manual Gear 5 (diagnostic mode), which is perfect for around town driving, but you'll notice the lack of 6th gear on the highway...

You can do the tune & replace hardware (AFM delete, new torque converter, etc...) and really extend the life of everything, but you pay more.

Like most projects, budget dictates decisions.
 

Joseph Garcia

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You have received excellent advice above.

The AFM mechanical delete can be performed by any local shop familiar with LS motors, and at a price far cheaper than the dealer. Texas Speed and Summit Racing sell AFM delete kits, and I suggest that you give them a call to discuss the kits and which one is specific to your truck. The removal and replacement of the mechanical AFM parts is the best way to delete AFM and increase the longevity of your motor.
 

donjetman

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Tranny - new fluid, filter, and torque converter. While you in that deep new rear main engine seal & cover, new oil pump pickup tube o-ring, remove & plug the pressure relief in/on the oil pan, dogbone, and replace the various seals o-rings on the tranny.

AFM - delete everything, like lifters, VLOM, oil pressure sender.

Must have it re-tuned
 

Joseph Garcia

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Tranny - new fluid, filter, and torque converter. While you in that deep new rear main engine seal & cover, new oil pump pickup tube o-ring, remove & plug the pressure relief in/on the oil pan, dogbone, and replace the various seals o-rings on the tranny.

AFM - delete everything, like lifters, VLOM, oil pressure sender.

Must have it re-tuned
I had just about all of that work done, while they had the body off the truck and the motor on the bench.
 

Marky Dissod

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is it good to delete AFM?
HELL YES.
Does it hurt anything?
Deleting AFM makes the engine last longer, although it may hurt to not have your vehicle while the Engine Half@$$ stuff is being deleted.
... and I guess I have to take it to a dealership to do it.
Cheaper to take to a NON-dealer mech that you trust.
Cheaper still to do it yself, although it will cost you more time that way.
If you can find a friend who has already done it, you both might get it done in a weekend.
One more thing is the 6L80 known to last? and what can I do to it to make it last longer?
Besides disabling / deleting Engine Half@$$, have your ecm & tcm tuned.
6L80s last longer with Engine Half@$$ disabled, so if you can't delete it yet, at least hurry up and disable it already.
 

dwkehoss

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Hi y’all .. is it good to delete my AFM? Does it hurt anything and I guess I have to take it to a dealership to do it.
2012 Gmc Yukon xl 5.3 . Oh one more thing is the 6 speed transmission known to last and what can I do to it to make it last longer ? 143,000 miles on the Yukon. Thank y’all!
I just installed two afm disablers in my 19 silverado ld and 16 tahoe. I can share more info if you wish
 

dwkehoss

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Hi y’all .. is it good to delete my AFM? Does it hurt anything and I guess I have to take it to a dealership to do it.
2012 Gmc Yukon xl 5.3 . Oh one more thing is the 6 speed transmission known to last and what can I do to it to make it last longer ? 143,000 miles on the Yukon. Thank y’all!
yes
 

swathdiver

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Hi y’all .. is it good to delete my AFM? Does it hurt anything and I guess I have to take it to a dealership to do it.
2012 Gmc Yukon xl 5.3 . Oh one more thing is the 6 speed transmission known to last and what can I do to it to make it last longer ? 143,000 miles on the Yukon. Thank y’all!
Dealerships cannot delete AFM, only repair it. That may change soon.

The tune is the basis upon which all other mods build upon and your greatest bang for the buck.

Dirty and worn out fluids are your drivetrains worst enemy. Run the severe service schedule from now on. Change your oil no later than 5K miles.
 

C1E2

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I just installed two afm disablers in my 19 silverado ld and 16 tahoe. I can share more info if you wish
How are those AFM disablers holding up? I'm thinking about plugging one in while I save for the full delete kit. I have a friend who's been a GM mechanic for a LONG time and I'm hoping to get his help when the time comes. I also have an extended warranty until July 2026 so I'm thinking I'll wait until then.
 

Maxentropy

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Have had one in my 14 yukon for over 100k, no engine issues. But I've got no clue if it saved me or I'm just not unlucky. Seems like a lot of folks run deep into the 200's with just reg oil changes.
 

Crazedtech85

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swathdiver is right on for clean fluids helping save especially the transmission.

In regards to deleting AFM it is Highly recommended to do it mechanically. This of course requires disable in the tune. Best place for info on this in my Biased opinion is Crazed Performance Repair. He has tons of usfull information here. The delete kits he offers are by far the most complete. He includes all the extras like spark plugs oil pan related stuff and even exhaust manifold bolts. That kit can be found here.

This guy also has a YouTube channel with guides and what not.
 

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