AFM questions years/models ?

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VWbuge

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Looking at trading my Terrain for something bigger. I've been doing a lot of research on AFM problems and vehicles in general. So I've been told if I want 2007 and up I should stay away from the 5.3 with AFM. However, during these years the 6.2 did NOT have AFM until 2010. So my question is did GM solve the AFM issues by 2011 and up body style?

I'm growing tired of searching for a needle in a haystack. With my budget I am looking to spend up to $20k. What should I be looking for? I realize not all vehicles run forever but I want reliability.
 

Geotrash

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Looking at trading my Terrain for something bigger. I've been doing a lot of research on AFM problems and vehicles in general. So I've been told if I want 2007 and up I should stay away from the 5.3 with AFM. However, during these years the 6.2 did NOT have AFM until 2010. So my question is did GM solve the AFM issues by 2011 and up body style?

I'm growing tired of searching for a needle in a haystack. With my budget I am looking to spend up to $20k. What should I be looking for? I realize not all vehicles run forever but I want reliability.
The short answer is no. They did improve the design and reduced the failure rate, but it's still a complex system that has multiple potential failure points. That said, you can take the failure risk down to near zero by tuning out the AFM system. The failures typically happen when one of the AFM lifters fails in its transition from locked to unlocked or vice versa. The root cause can be an oil pressure loss somewhere in the system (e.g. in the VLOM), a piece of grit in the way, who knows. But tuning it out leaves all of the lifters in their locked position and deactivates the VLOM, essentially making the lifters as reliable as standard lifters from then on. I deleted the AFM in my 2012 with a cam swap, but with what I know about the AFM system now, I wouldn't bother with it and would just have it tuned out.

There is a place that will do this service on a mail order basis for $50, or you can have it tuned out by a local tuner or buy a Range dongle that will turn it off also. Black Bear Performance can tune it out via email as well but also deliver you a custom tune for your truck that will wake up its performance and improve transmission life and performance.

If I were in your shoes with that budget, I would be looking for a Denali and AFM wouldn't scare me away. That 6.2 is a sweetheart of an engine but you gotta run premium in it.
 
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VWbuge

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The short answer is no. They did improve the design and reduced the failure rate, but it's still a complex system that has multiple potential failure points. That said, you can take the failure risk down to near zero by tuning out the AFM system. The failures typically happen when one of the AFM lifters fails in its transition from locked to unlocked or vice versa. The root cause can be an oil pressure loss somewhere in the system (e.g. in the VLOM), a piece of grit in the way, who knows. But tuning it out leaves all of the lifters in their locked position and deactivates the VLOM, essentially making the lifters as reliable as standard lifters from then on. I deleted the AFM in my 2012 with a cam swap, but with what I know about the AFM system now, I wouldn't bother with it and would just have it tuned out.

There is a place that will do this service on a mail order basis for $50, or you can have it tuned out by a local tuner or buy a Range dongle that will turn it off also. Black Bear Performance can tune it out via email as well but also deliver you a custom tune for your truck that will wake up its performance and improve transmission life and performance.

If I were in your shoes with that budget, I would be looking for a Denali and AFM wouldn't scare me away. That 6.2 is a sweetheart of an engine but you gotta run premium in it.
So for very little money the AFM can be deleted WITHOUT changing any hard parts? Just software?
 

Bill 1960

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So for very little money the AFM can be deleted WITHOUT changing any hard parts? Just software?
Disabled, not deleted.

My opinion, just from a numbers perspective, there are other issues of greater concern when buying a GMT900. Transmission especially. Four speeds are a big liability if original at this age, or if not original then rebuilt by whom?
Six speeds there’s the torque converter issue.

I’d say the chances of having lifters fail in an engine with proper maintenance-which is nothing more than clean oil- is less a probable failure in the next few years than encountering a big transmission repair.

I’d shop for the latest year and lowest mileage I could afford, and specifically look for maintenance history. Oil changes, transmission service, brakes, coolant, tires. The more records the better.
 

Just Fishing

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also try and get one with a low owner count.

Best if you buy it from the original owner, you can get the real story about what type of oil they used etc.
I use carfax to get a general idea of cars to look at.

With my hoe i tossed that right out the window and went with the one that had a 6 speed and had the (rare) color i wanted. :jester:
I'm paying for that mistake.
Paying for it i am. :nolol:
 

swathdiver

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Looking at trading my Terrain for something bigger. I've been doing a lot of research on AFM problems and vehicles in general. So I've been told if I want 2007 and up I should stay away from the 5.3 with AFM. However, during these years the 6.2 did NOT have AFM until 2010. So my question is did GM solve the AFM issues by 2011 and up body style?

I'm growing tired of searching for a needle in a haystack. With my budget I am looking to spend up to $20k. What should I be looking for? I realize not all vehicles run forever but I want reliability.

Chevrolet or GMC? Tahoe or Suburban? Yukon or Yukon XL? RWD, AWD or 4x4?

Don't sweat the AFM thing. It scared most of us until we learned more about it. It's not a big deal to fix if it fails or to disable in one way or another.

With that budget you can get a 2009 or newer, preferably 2012 or newer as they have all the latest improvements, not all of which you can see but can and are helpful.
 
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VWbuge

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Thanks a ton for your help guys. Hopefully heading to a place about 3 hours from me in VA. They have at least a half dozen on the lot.
 
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VWbuge

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Chevrolet or GMC? Tahoe or Suburban? Yukon or Yukon XL? RWD, AWD or 4x4?

Don't sweat the AFM thing. It scared most of us until we learned more about it. It's not a big deal to fix if it fails or to disable in one way or another.

With that budget you can get a 2009 or newer, preferably 2012 or newer as they have all the latest improvements, not all of which you can see but can and are helpful.
Looking at either Tahoe or Yukon. 4WD or AWD. I'd like to stay away from the Suburban. I am going to look at a 2013 Tahoe today. Nice looking truck with lots of service records. 150k miles. They are asking $17k.
 

BG1988

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Thanks a ton for your help guys. Hopefully heading to a place about 3 hours from me in VA. They have at least a half dozen on the lot.
don't pay full price the VALUE if SUV is less when gas price are high


only worth 14-15k with 150k
 
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