2012 Yukon 6.2 Denali with AFM

[bobsr]

Hello,

Is the AFM the old 8-6-4 which reduced the number of cylinders the engine has running at any given time?

Is that what a 2012 6.2 Denali with a AFM would have? Was this engine available in 2012 with or without this AFM? Loklng at a used one with about 100,000 miles which has AFM. Seems it might be an issue.

Thanks.

 

[Doubeleive]

pretty sure all the 2012 have AFM, you would need to either turn it off with a tune, or do a hardware delete and have the ecm re programmed to completely remove it and by doing that I believe you loose the flex fuel capability but I could be wrong. @swathdiver probably has more info

 

[the_tool_man]

bobsr:

I just bought exactly the same thing; a 2012 Yukon Denali 6.2 with AFM and 99k miles. The system came on all of these vehicles from the factory.

First of all, while the concept is the same as the old 8-6-4 system from the early 1980's, the actual implementation is vastly better. Modern electronics and variable valvetrain geometry have supplanted the jury-rigged, primitive systems of old. When it works, it works very well, and isn't especially noticeable unless you have an aftermarket exhaust system, which audibly reveals V4 mode. GM decided to develop the system and install it on many vehicles to help them meet government CAFE requirements. Anecdotally, the savings is around 5% on average. Actual fuel savings varies with terrain and driving style.

Secondly, by 2012, it is my understanding that the system had become pretty reliable, provided proper oil change intervals were followed. The system relies on solenoid valves to divert oil pressure to retractable pins on the valve lifters, allowing them to collapse. Dirty oil reduces the likelihood that this system will work properly.

Thirdly, having said that, with unknown service history and the accumulation of miles, it stands to reason that AFM is nevertheless a potential failure point. For that reason, I chose to deactivate AFM on my Yukon shortly after I bought it. I did this using a custom tune. There is a plug-in device, called a Range module, that effectively does the same thing. After studying the operation of the AFM system, I determined that if it is never actuated, there is no risk of failure; at least none that I can determine. For me, the mileage benefit of AFM was negligible. And I wanted the peace of mind of knowing the valvetrain would last.

I would not, and did not let the existence of AFM deter me from buying what is otherwise an excellent vehicle with a fantastic engine.

 

[bobsr]

pretty sure all the 2012 have AFM, you would need to either turn it off with a tune, or do a hardware delete and have the ecm re programmed to completely remove it and by doing that I believe you loose the flex fuel capability but I could be wrong. @swathdiver probably has more info

Thanks for your comments. I have a 2003 Yukon with the 5.3 with now 325,000 + miles, and have been running Mobil 1 5W-30 since new. Ordered this and it took me 5 months to get it in 2002, and I hate losing the "barn doors" with no third seat. Minimal problems until now, with increased oil usage and small things failing that make my wife nervous. TIme to get something newer, and the 2012 with around 100,000 looks promising.

I have the dark bue SLT with auto ride and most options, including the then new "flex fuel" option. MAYBE used it once when in Pennsylvania and I bought some of that fuel. But I did have to replace some kind of a valve for that system and that cost me $700-- at the dealer. So the "flex fuel" option was a bad choice. But now I guess they all come with it. We still don't have that fuel generally available in New England.

 

[swathdiver]

Thanks for your comments. I have a 2003 Yukon with the 5.3 with now 325,000 + miles, and have been running Mobil 1 5W-30 since new. Ordered this and it took me 5 months to get it in 2002, and I hate losing the "barn doors" with no third seat. Minimal problems until now, with increased oil usage and small things failing that make my wife nervous. TIme to get something newer, and the 2012 with around 100,000 looks promising.

I have the dark bue SLT with auto ride and most options, including the then new "flex fuel" option. MAYBE used it once when in Pennsylvania and I bought some of that fuel. But I did have to replace some kind of a valve for that system and that cost me $700-- at the dealer. So the "flex fuel" option was a bad choice. But now I guess they all come with it. We still don't have that fuel generally available in New England.

Howdy Bob. John laid out the features and how most of folks deal with AFM succinctly. I will only add that the Flex Fuel capability is not lost when de-activating AFM and that this generation does not use that special and expensive FlexFuel sensor. These engines run great on E85.

Is the Denali you're looking at 2WD or AWD?

 

[bobsr]

Howdy Bob. John laid out the features and how most of folks deal with AFM succinctly. I will only add that the Flex Fuel capability is not lost when de-activating AFM and that this generation does not use that special and expensive FlexFuel sensor. These engines run great on E85.

Is the Denali you're looking at 2WD or AWD?

Hello,

Thanks for your comments. The Denali I am looking at has AWD and most options. 100,000 miles and records seem to be clean.
I live where we get snow and ice and salt etc on the roads in the winter. I try to wash vehicles regularly in the WInter. The 2003 I think has the 4wd system which has been excellent with no issues.


I doubt if the 100,000 miles extensive service was done, but maybe this has a different service schedule than a 2003. Dealer charged me about $ 1,000 to do it, with a tune up, all fluids changed etc etc. back then.

I would suspect a service contract might be in order for this vehicle.

Any comments on those? I know there are a bunch of scams out there, but I think the new and used car dealers also offer these, including the seller of the vehicle I am looking at. But I don't have the details yet. Have to drive a couple of hours today to actually look at the vehicle for sale from a used car dealer.

 

[swathdiver]

Hello,

Thanks for your comments. The Denali I am looking at has AWD and most options. 100,000 miles and records seem to be clean.
I live where we get snow and ice and salt etc on the roads in the winter. I try to wash vehicles regularly in the WInter. The 2003 I think has the 4wd system which has been excellent with no issues.


I doubt if the 100,000 miles extensive service was done, but maybe this has a different service schedule than a 2003. Dealer charged me about $ 1,000 to do it, with a tune up, all fluids changed etc etc. back then.

I would suspect a service contract might be in order for this vehicle.

Any comments on those? I know there are a bunch of scams out there, but I think the new and used car dealers also offer these, including the seller of the vehicle I am looking at. But I don't have the details yet. Have to drive a couple of hours today to actually look at the vehicle for sale from a used car dealer.

No experience with them but Wes might know. Check everything, every knob and switch and feature including the cruise control and heated steering wheel, cooling seats, side blind zone, back up camera, moonroof, power seats front to rear, etc.

When you drive it, set the driver's information center to the instant mpg so you can see when she goes into V4 mode and feel for that. Should be seemless or nearly so.

Good luck!

 

[bobsr]

No experience with them but Wes might know. Check everything, every knob and switch and feature including the cruise control and heated steering wheel, cooling seats, side blind zone, back up camera, moonroof, power seats front to rear, etc.

When you drive it, set the driver's information center to the instant mpg so you can see when she goes into V4 mode and feel for that. Should be seemless or nearly so.

Good luck!

Great advice! Thanks. Haven't bought a used vehicle for probably 40 years. But 60 + grand for a new Yukon seems over the top. Have to spend a lot of time reading the instructions for all that new (to me) stuff like rear camera, side blind zone, cell phone integration, and the whole driver information center. I had the OEM suplied XM radio back then, and on star (never used it or paid for it), and a pretty basic (by todays standards) driver information center. But at the time, it was a big deal. My average for 325,000 miles: 16 mpg .

No GPS at that time, except my Magallan GPS system stuck on to the windshield, with the antenna through the moon roof. Cost me over $1,000 at that time from Costco. But was magic for a guy on the road a lot for business. But I had learned how to use it because it was the same system Hertz first used. All this technlogy is only as good as your ability to learn how to use it and then using it frequently enough not to forget how to use it. It's still not natural for me to even remember I have a camera in my cell phone...But I carried a 35mm Leicaflex and 3 lenses around the world for over 40 years... the same one!

Thanks again. WIll see how things work out.

 

[Sangster]

No bluetooth audio streaming, unfortunately

 

[swathdiver]

Great advice! Thanks. Haven't bought a used vehicle for probably 40 years. But 60 + grand for a new Yukon seems over the top. Have to spend a lot of time reading the instructions for all that new (to me) stuff like rear camera, side blind zone, cell phone integration, and the whole driver information center. I had the OEM suplied XM radio back then, and on star (never used it or paid for it), and a pretty basic (by todays standards) driver information center. But at the time, it was a big deal. My average for 325,000 miles: 16 mpg .

No GPS at that time, except my Magallan GPS system stuck on to the windshield, with the antenna through the moon roof. Cost me over $1,000 at that time from Costco. But was magic for a guy on the road a lot for business. But I had learned how to use it because it was the same system Hertz first used. All this technlogy is only as good as your ability to learn how to use it and then using it frequently enough not to forget how to use it. It's still not natural for me to even remember I have a camera in my cell phone...But I carried a 35mm Leicaflex and 3 lenses around the world for over 40 years... the same one!

Thanks again. WIll see how things work out.

Most folks complain about the factory navigation but I love it. Just have to figure a way to keep it updated as the last one was 2016. The looks and screen was little different from a Pacifica we rented two years ago so maybe there's a way. I've yet to locate a mapping/navigation company offer an update other than the folks GM contracted with.

 

[gooffeyguy]

Most folks complain about the factory navigation but I love it. Just have to figure a way to keep it updated as the last one was 2016. The looks and screen was little different from a Pacifica we rented two years ago so maybe there's a way. I've yet to locate a mapping/navigation company offer an update other than the folks GM contracted with.

Yup, pre 2012 was able to update with a cheap DVD copy. 2012+ is with a DVD but it is locked to your VIN when you order it.

2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18

 

[donjetman]

Yup, pre 2012 was able to update with a cheap DVD copy.

Where can I get the cheap latest greatest DVD copy please??? thank you

 

[gooffeyguy]

Where can I get the cheap latest greatest DVD copy please??? thank you

Ebay for about $9-$13

2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18

 

[juan84]

I beleive in 09 the 6.2 denali didn't have afm dod at least mine didn't not sure about others

Sent from my SM-G920T using Tapatalk

 

[bobsr]

Thanks for all your advice above. We did buy the 2012 red Yukon Denali from a used car dealer in Conneticut this week, with a little more then 98,000 miles. It was about a 3 hour drive from here, and we went down and looked at it, and decided to buy it, and came back without it to work out the details.The next day my 2003 Yukon SLT had zero oil pressure and bad engine sounds when I started it. So I had to rent a car to go back down there and pick up the "new" vehicle. So now I have to figure out what to do with it.

The 2012 seems in great shape and was GMC dealer serviced since new. But the 97,000 mile recommended maintenance was not done (new plugs, transfer case oil, and transmission oil) of coursde so it looks like that needs to be done. Dash also has a crack behind the instrument panel so it's not that noticeable.I read this is a common problem for the 2012. No problem for the 2003.

The instruction manual is about 1.5" thick and the technology of the electronics is staggering to have to learn and understand.

But even the basics are difficult. GM Recommends ("requires" because of warrranty issues) the GM Dexos oil (or equivalent) which is a synthetic oil. So I looked at the list of approved oils on the GM Website and will have to follow that. I am convinced I got 325,000 miles on my 2003 Ykkon with the 5.3 because of Mobil 1. But in order to try to do that again, it would probably be useful to read these owners manuals and do what they suggest.

The gasoline they recommend is supposed to carry the "top tier" logo, which most of the major brand stations do. There is a list of approved ones on the top tier site. THey also recommend 91 octane, but say you can use 85 and see if it doesn't knock. No MMT.
I presume there is probably a discussion topic about all this on the forum for all these GM vehicles using this DEXOS since 2011, and the gasoline experiience but I have not yet looked. WIth this 6.2 with the FMT, it would appear that for that system to be kept in good shape you need the DEXOS oil and gasoline specs with those additives. But then I guess I can't use the "nameless brand" gas that is a lot less money per gallon.

I stil haven't figured out how to remove the trailer hitch cover , but it has not been above freezing since we got the vehicle. Any one can pass on that information for me? i didn't find it in the book yet.

Seems like it wil be a great ride with a whole lot of improvements since the 2003 SLT, and my wife loves it. Still need to figure out now what to do with the 2003... Fix it and keep it, or unload it for probably next to nothing.

 

[gooffeyguy]

Thanks for all your advice above. We did buy the 2012 red Yukon Denali from a used car dealer in Conneticut this week, with a little more then 98,000 miles. It was about a 3 hour drive from here, and we went down and looked at it, and decided to buy it, and came back without it to work out the details.The next day my 2003 Yukon SLT had zero oil pressure and bad engine sounds when I started it. So I had to rent a car to go back down there and pick up the "new" vehicle. So now I have to figure out what to do with it.

The 2012 seems in great shape and was GMC dealer serviced since new. But the 97,000 mile recommended maintenance was not done (new plugs, transfer case oil, and transmission oil) of coursde so it looks like that needs to be done. Dash also has a crack behind the instrument panel so it's not that noticeable.I read this is a common problem for the 2012. No problem for the 2003.

The instruction manual is about 1.5" thick and the technology of the electronics is staggering to have to learn and understand.

But even the basics are difficult. GM Recommends ("requires" because of warrranty issues) the GM Dexos oil (or equivalent) which is a synthetic oil. So I looked at the list of approved oils on the GM Website and will have to follow that. I am convinced I got 325,000 miles on my 2003 Ykkon with the 5.3 because of Mobil 1. But in order to try to do that again, it would probably be useful to read these owners manuals and do what they suggest.

The gasoline they recommend is supposed to carry the "top tier" logo, which most of the major brand stations do. There is a list of approved ones on the top tier site. THey also recommend 91 octane, but say you can use 85 and see if it doesn't knock. No MMT.
I presume there is probably a discussion topic about all this on the forum for all these GM vehicles using this DEXOS since 2011, and the gasoline experiience but I have not yet looked. WIth this 6.2 with the FMT, it would appear that for that system to be kept in good shape you need the DEXOS oil and gasoline specs with those additives. But then I guess I can't use the "nameless brand" gas that is a lot less money per gallon.

I stil haven't figured out how to remove the trailer hitch cover , but it has not been above freezing since we got the vehicle. Any one can pass on that information for me? i didn't find it in the book yet.

Seems like it wil be a great ride with a whole lot of improvements since the 2003 SLT, and my wife loves it. Still need to figure out now what to do with the 2003... Fix it and keep it, or unload it for probably next to nothing.

For the hitch cover, there are 2 twist-lock 1/4 turn tabs on the bottom. Turn them and pull the panel down and out. It has tabs across the top that fit into slots in the bumper.

This video is for a 2015+ but it's basically the same....

2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18

 

[bobsr]

Thanks for the info on the hitch cover. Had a major problem with my 2003 spare tire mechanism. Apparently no dealer or anyone else ever lubed it, so of course when I needed it once, the salt had totally seized it up. Mechanic finally had to literally cut it away making the system un-useabe. So I carried the spare in the back, but without that third seat, it was no problem. But AAA had to tow the vehicle in because the spare tire could not be lowered.

Anyone else have this issue? I presume the system being totally exposed to the water, wind, snow and salt has a difficult life without some maintenance.

 

[bobsr]

For the hitch cover, there are 2 twist-lock 1/4 turn tabs on the bottom. Turn them and pull the panel down and out. It has tabs across the top that fit into slots in the bumper.

This video is for a 2015+ but it's basically the same....

2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18

 

[bobsr]

Thanks for the video! If my wife had to try to do that at night to get the spare down, the only way would be that you already knew how to do it. But if it happened she would call AAA and have them do it. Flat tires are uncommon, but in most cases you want to be out of the vehicle and way off the roadway so someone doesn't run into you.

 

[swathdiver]

That's great Bob. Yes, it is good practice to inspect and operate the spare tire hoist at least once or twice a year. Mine failed too last year. Mobil 1 oil is Dexos approved. Run top-tier 91 or 93 in your Denali. Exxon is pretty much the best with Mobil a close second. Sunoco isn't bad either. Record your mileage readings and see which works best for you. Around here Shell is terrible but a fella in high altitudes does great with it. Get a Tech-2 so you can work on it. Keep the fluids clean in it and use GM OE or ACDelco Professional parts.

You'll see tons of posts by me and others repeating the part numbers and quantity of fluids for the differentials, trans, transfer case, etc. Same for plugs, wires, air cleaners, etc.