Different DOD/AFM delete/disable questions

[Roger Hill]

I'm looking at jumping into a '12-'14 Tahoe and have been reading A LOT about the delete/disable and I still have questions:

1). How common is this issue? Are these motors ticking time bombs or is it just "one of those things"?

2). If the truck currently doesn't have issues, is it just as good to disable rather then the expense of deleting?

3). For the 12-14 models, is there one year that is less likely or is it the luck of the draw?

4). For those of you that deleted and didn't upgrade the cam or anything (stayed stock), how much did it cost for a shop to do the work?

Thanks for answering "yet another AFM question".

 

[wsteele]

I'm looking at jumping into a '12-'14 Tahoe and have been reading A LOT about the delete/disable and I still have questions:

1). How common is this issue? Are these motors ticking time bombs or is it just "one of those things"?

2). If the truck currently doesn't have issues, is it just as good to disable rather then the expense of deleting?

3). For the 12-14 models, is there one year that is less likely or is it the luck of the draw?

4). For those of you that deleted and didn't upgrade the cam or anything (stayed stock), how much did it cost for a shop to do the work?

Thanks for answering "yet another AFM question".

It appears the most problematic issues with AFM lifters was in the earlier model years (like 2007-2009). Along the way GM made a number of upgrades to the AFM components that make the kind of failures prevalent in earlier model year far less so. I think 2012-2014 have all the upgrades, plus other moves GM made to make these engines better, like the upgraded valve cover, AFM relief valve deflector, etc.

It appears the biggest single factor in keeping these AFM engines out of trouble is regular oil changes. If you find an example with excellent service history you are way ahead of the game.

As far as turning AFM off (so the engine never drops into V4 mode and hence risk a collapsed lifter), there are very experienced guys that will do that for as little as $50. There are a lot of options on turning it off, simple to very complex.

 

[Jettix2]

I disabled mine when I bought our 2014 Escalade (30k miles at the time) with a Black Bear Tune.........obviously doesn't change the mechanicals, but it prevents the DOD/AFM from engaging. Runs and drives 100x better with the Black Bear Tune........

 

[Roger Hill]

It appears the most problematic issues with AFM lifters was in the earlier model years (like 2007-2009). Along the way GM made a number of upgrades to the AFM components that make the kind of failures prevalent in earlier model year far less so. I think 2012-2014 have all the upgrades, plus other moves GM made to make these engines better, like the upgraded valve cover, AFM relief valve deflector, etc.

It appears the biggest single factor in keeping these AFM engines out of trouble is regular oil changes. If you find an example with excellent service history you are way ahead of the game.

As far as turning AFM off (so the engine never drops into V4 mode and hence risk a collapsed lifter), there are very experienced guys that will do that for as little as $50. There are a lot of options on turning it off, simple to very complex.

Thank you for the info. If I should ever notice the oil not being proper pressure and it's not throwing codes, that would of be a good indication? If it's early on and the engine hasn't grenades, can I then use a disabler instead of delete?

 

[Roger Hill]

I disabled mine when I bought our 2014 Escalade (30k miles at the time) with a Black Bear Tune.........obviously doesn't change the mechanicals, but it prevents the DOD/AFM from engaging. Runs and drives 100x better with the Black Bear Tune........

Does it have a tune that can give even slightly better fuel mileage? The reason I ask, is when I deleted my truck (Dodge 3500) and tuned it, my power, performance and fuel mileage shot up.

 

[wsteele]

Thank you for the info. If I should ever notice the oil not being proper pressure and it's not throwing codes, that would of be a good indication? If it's early on and the engine hasn't grenades, can I then use a disabler instead of delete?

If you get a collapsed AFM lifter (pretty rare, even though the internet makes it seem like it happens to every truck), you will get a misfire on that cylinder P030x, with X being 1, 4, 6 or 7 (the AFM cylinders). If you get that and you pop the valve cover off the bank that has the misfire, you will likely see the rocker kind of flopping around and the valve staying closed.

 

[Jettix2]

Does it have a tune that can give even slightly better fuel mileage? The reason I ask, is when I deleted my truck (Dodge 3500) and tuned it, my power, performance and fuel mileage shot up.

You could email Black Bear and ask.............my mileage drops with the tune, partly because the AFM is disabled, and partly because I have a lead foot LOL

 

[iamdub]

Does it have a tune that can give even slightly better fuel mileage? The reason I ask, is when I deleted my truck (Dodge 3500) and tuned it, my power, performance and fuel mileage shot up.

Kinda repeating what @wsteele said:

Improvements were made 2010-2011 and up that drastically improved the reliability of the system.

Keeping impeccably clean oil in the engine is paramount in avoiding issues with the system.

I'd still disable it to at least "kick the can down the road". You can send your PCM to a guy that disables it for $50. I wouldn't use the plug-in type disabler since there may be times you need that ALDL ("OBD") port open for diagnostics or for vehicle inspection. For those times, you'd have to unplug it, enabling the AFM system that has sat dormant for who-knows-how-long. You'd also have to wait for all the readiness monitors to set after unplugging it, which requires considerable drive time.

From my experience, AFM in the GMT900s doesn't improve the fuel economy enough to risk keeping it. If the vast majority of your travels were on flat land with no head wind, no traffic and at speeds not exceeding 60MPH, THEN, it may eventually benefit you if it never has a failure. I deleted mine with a performance cam and some other mods. I have a lot more power (gained a full second in the 1/4 mile) and get better mileage now than I did with AFM. The engine was in top shape inside and out so it's not that it had something wrong with it prior to deleting it.

 

[Roger Hill]

Kinda repeating what @wsteele said:

Improvements were made 2010-2011 and up that drastically improved the reliability of the system.

Keeping impeccably clean oil in the engine is paramount in avoiding issues with the system.

I'd still disable it to at least "kick the can down the road". You can send your PCM to a guy that disables it for $50. I wouldn't use the plug-in type disabler since there may be times you need that ALDL ("OBD") port open for diagnostics or for vehicle inspection. For those times, you'd have to unplug it, enabling the AFM system that has sat dormant for who-knows-how-long. You'd also have to wait for all the readiness monitors to set after unplugging it, which requires considerable drive time.

From my experience, AFM in the GMT900s doesn't improve the fuel economy enough to risk keeping it. If the vast majority of your travels were on flat land with no head wind, no traffic and at speeds not exceeding 60MPH, THEN, it may eventually benefit you if it never has a failure. I deleted mine with a performance cam and some other mods. I have a lot more power (gained a full second in the 1/4 mile) and get better mileage now than I did with AFM. The engine was in top shape inside and out so it's not that it had something wrong with it prior to deleting it.

Would you know who it is to send the PCM to?

 

[wsteele]

The reason Chris is agreeing with me is I learned all this stuff from him and a few other experts on these threads.