Anyting I can do to prevent AFM issues?

Roger08LTZ

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My 2008 Tahoe 5.3 is running fine now, but i've been reading up on all of the AFM issues. I see the Range Technology AFM Disabler. Most people seem to be buying them for performance or exhaust note reasons, but I was woundering if using this or some other method to disable AFM will make the lifters last longer? My thought is if the lifters don't collapse they can't get stuck. Assuming I don't really care about sound or power, will a AFM disabler really help avoid the issue? Worth doing? My car has 190K on it, if it's lasted this long, perhaps I have good lifters and shoulden't bother?


Thanks!
 

OR VietVet

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Best thing I found to avoid the dreaded AFM problem is............buy a NBS 2000 to 2006 rig.
 

iamdub

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My 2008 Tahoe 5.3 is running fine now, but i've been reading up on all of the AFM issues. I see the Range Technology AFM Disabler. Most people seem to be buying them for performance or exhaust note reasons, but I was woundering if using this or some other method to disable AFM will make the lifters last longer? My thought is if the lifters don't collapse they can't get stuck. Assuming I don't really care about sound or power, will a AFM disabler really help avoid the issue? Worth doing? My car has 190K on it, if it's lasted this long, perhaps I have good lifters and shoulden't bother?


Thanks!

At 190K, your clock is ticking. Keeping the system disengaged (lifters locked) certainly seems to be the second best option next to a mechanical deletion of the system. Have you owned your '08 for all 190K miles or at least know its maintenance and repair history? An '08 would have the oldest rendition of the AFM components unless it has been upgraded, which is usually done following a failure. Upgrades were made to the lifters and VLOM and a couple other parts were revised during this generation starting in 2010-2011. Regardless, the fuel savings will never outweigh the risk of keeping AFM active.

Instead of a plug-in device, I'd strongly recommend having AFM tuned out. You can have this done for as little as $50 plus cost of shipping your PCM (~$15?). You'll just have to remove you PCM and have your Tahoe out of commission for a few days. IMO, still a far better option than $200+ for a plug-in module that will still require tending to. For $65, you can "set it and forget it". And if you ever have a mechanical failure and need to do a delete, the PCM won't require any programming- swap the parts and get back on the road.

Go here: https://lt1swap.com/afm_delete.htm

Also, do you monitor your oil level? AFM contributes to oil consumption but there's also an upgraded driver side valve cover that really helps, too. This is another item introduced around 2010 that yours should get if it hasn't gotten it already.

Speaking of oil levels, a huge killer of the AFM system is dirty oil due to improper maintenance. The system is sensitive to sludge. Yours lasting so long tells me you keep up clean oil in it or are just lucky. AFM disabled or not, stay on top of your oil changes.
 
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Roger08LTZ

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Well I've only had this car a little over 1 year and I have no idea on prior maintenance except that it's in really nice shape which indicates overall care, but no guarentee good oil change maintenance. Many people care for the car, but push oil changes. Oil Consumption is zero or close to it, so that's a good sign. I very much like the reprogramming option! I actually do have a spare PCM due to a mis-diagnosis discussed on another thread, so I might not even be offline. This brings another question When I swepped in the "New" PCM the car started, but had the same issue I was chasing, plus a bunch more. I did'nt record all of the codes, but one was something like Crank sensor relearn, others related to comunication to other modules. As I was not in the mood to start chasing new problems, I swapped back to my stock PCM and found the real issue (a bad ground of course!). Anyway, Any idea what's involved in getting a new PCM to be happy in it's new home? I do plan to swap it back sometime and attempt to solve this lssue just so I know I have a good PCM in reserve since I bought it already.

Thanks!
 

iamdub

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Well I've only had this car a little over 1 year and I have no idea on prior maintenance except that it's in really nice shape which indicates overall care, but no guarentee good oil change maintenance. Many people care for the car, but push oil changes. Oil Consumption is zero or close to it, so that's a good sign. I very much like the reprogramming option! I actually do have a spare PCM due to a mis-diagnosis discussed on another thread, so I might not even be offline. This brings another question When I swepped in the "New" PCM the car started, but had the same issue I was chasing, plus a bunch more. I did'nt record all of the codes, but one was something like Crank sensor relearn, others related to comunication to other modules. As I was not in the mood to start chasing new problems, I swapped back to my stock PCM and found the real issue (a bad ground of course!). Anyway, Any idea what's involved in getting a new PCM to be happy in it's new home? I do plan to swap it back sometime and attempt to solve this lssue just so I know I have a good PCM in reserve since I bought it already.

Thanks!

From where did you get the replacement PCM? From a salvage yard? First, it needs to be a match to your vehicle and it will need programming. It might have been from a different year and/or model with different powertrain options. A crank sensor relearn is always needed any time a CKP sensor is replaced or the PCM is replaced. You might have to have that PCM programmed and operational before sending it to LT1Swap because I don't think they can do anything for that. Or, if they can, it might just be a few bucks more. I don't know their resources but I'd bank on having it done locally and sending it out after you confirm it works, if you must avoid decommissioning your Tahoe for a few days.

If you wanna learn more of the health of your engine, pop off that driver side valve cover. It's about a 30-minute job moving casually and using basic hand tools. You'll be able to see if it has been updated as well as see the internals of the engine to gauge the previous maintenance and if/how you should proceed with future maintenance.
 
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Roger08LTZ

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From where did you get the replacement PCM? From a salvage yard? First, it needs to be a match to your vehicle and it will need programming. It might have been from a different year and/or model with different powertrain options. A crank sensor relearn is always needed any time a CKP sensor is replaced or the PCM is replaced. You might have to have that PCM programmed and operational before sending it to LT1Swap because I don't think they can do anything for that. Or, if they can, it might just be a few bucks more. I don't know their resources but I'd bank on having it done locally and sending it out after you confirm it works, if you must avoid decommissioning your Tahoe for a few days.

If you wanna learn more of the health of your engine, pop off that driver side valve cover. It's about a 30-minute job moving casually and using basic hand tools. You'll be able to see if it has been updated as well as see the internals of the engine to gauge the previous maintenance and if/how you should proceed with future maintenance.
I got the PCM from Flagship One https://www.fs1inc.com/ they programmed the VIN into it and the factory key worked and it started and ran. I have not attempted to contact them for support as this was not my real issue, but I will. I'll definately pull that valve cover and post some pics.

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iamdub

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I got the PCM from Flagship One https://www.fs1inc.com/ they programmed the VIN into it and the factory key worked and it started and ran. I have not attempted to contact them for support as this was not my real issue, but I will. I'll definately pull that valve cover and post some pics.

Thanks

Cool! Then the problems it had might have just been needing the CKP relearn and fixing the actual/original problem, which was that ground. A shop or someone with a Tech2 or capable bi-directional scan tool can perform the relearn in about a minute. Supposedly, you can get it to relearn by performing a very specific drive cycle. But, it'll likely not happen unless you can travel for miles at a particular speed with no stops or other traffic around for the duration. I'd do it the standard way. If it works, leave it in and send off your original or vice-versa. Then send off the other so you won't have to worry about AFM being abruptly taken out of deep hibernation if you ever need to swap in that PCM.
 
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Roger08LTZ

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I recently purchased an Xtool D8 scanner which seems to have the crank sensor learn feature. I'm new to scan tools other than code readers, so it's a learning experience.
 

iamdub

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I recently purchased an Xtool D8 scanner which seems to have the crank sensor learn feature. I'm new to scan tools other than code readers, so it's a learning experience.

Aw, hell! You're set up! What're you waiting for? Let's see if that new PCM is good to go!
 

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