Did 2007 Denalis have AFM in the 6.2 ?

[okfoz]

No, I have not done the Valve cover... I am curious, it does not leak, why would that change my c

Have you installed the updated drivers side valve cover? I did that on my 07 and it reduced my oil consumption to about 1/3 of what it used to be. I burn a little over half a quart every 2,000 miles now. Can't wait to turn off AFM and hopefully that will help. Would really like to delete it this summer.

No, I have not changed my valve cover, I am curious, it does not leak, why would changing it make a difference?

 

[R3cord303]

No, I have not done the Valve cover... I am curious, it does not leak, why would that change my c


No, I have not changed my valve cover, I am curious, it does not leak, why would changing it make a difference?

2007 and 2008 model years on the 5.3s (maybe the other engines too?) had the inlet over top of a rocker arm, so when the engine went into 4 cyl mode oil shoots out of the lifters and up the pushrods, and directly into that port which has vacuum being drawn thru it, so the engine was sucking in its own oil. The new valve cover moved the inlet to somewhere else on the valve cover. IIRC it was like $100 on amazon, came with all seals pre installed, and new bolts even. Took me like 15/20 min to change it in the driveway. All you have to do is pull the coil bracket off, pull the pcv tube, pull the three bolts holding the cover to the engine, open the new one, and reverse the process. Its part of the oil consumption TSB. There is other stuff in the tsb like adding a $6 oil deflector to the oil pump return in the oil pan, which will reduce the oil vapors in the crank case which is what the PCV system is intended to suck in. less overall oil vapor, less oil consumption. I haven't done that but I will if I ever need to have the oil pan off.

I bought my tahoe from my grandfather because he got a 2013 model. This gold one has burnt a quart every thousand sense he got it at ~90,000 miles. I bought it from him at 215,000. He had been dumping a quart in every thousand miles. I changed the valve cover and now I'm at a half quart every 2,000.

 

[MLRTYME]

The very earliest engines had AFM hardware but it was not active in the tune. I think these motors were made before April 2005 or 2006, don't remember. You can tell whether an engine has it or not by looking under the intake at the valley cover. If it is flat, no AFM. If it is lumpy with raised passages, that's the VLOM for AFM. Again, it's not active in the tune in those early motors.

Swath...how can a person tell if they have an 'early' version of the Denali w/o AFM? You stated the AFM hardware is there (so I would assume the lifter valley cover would have the raised passages), but the AFM is deactivated in the tune. IF that is the case, are there any other giveaways on these rare birds?

I ask as I'm looking at a possible purchase of that exact rig and would LOVE to have one that doesn't have the AFM active in the tune...

 

[swathdiver]

2007 and 2008 model years on the 5.3s (maybe the other engines too?) had the inlet over top of a rocker arm, so when the engine went into 4 cyl mode oil shoots out of the lifters and up the pushrods, and directly into that port which has vacuum being drawn thru it, so the engine was sucking in its own oil. The new valve cover moved the inlet to somewhere else on the valve cover.

This is the best explanation I've ever seen and now fully understand it myself! Thanks Allen!

Swath...how can a person tell if they have an 'early' version of the Denali w/o AFM? You stated the AFM hardware is there (so I would assume the lifter valley cover would have the raised passages), but the AFM is deactivated in the tune. IF that is the case, are there any other giveaways on these rare birds?

I ask as I'm looking at a possible purchase of that exact rig and would LOVE to have one that doesn't have the AFM active in the tune...

I often write that those motors were made before April 2006 but I'm now pretty sure it was April 2005. So these would be the very earliest trucks, the Tahoes and Yukons entered production first in December 2005 and the longer ones began production in March. I doubt the longer ones would have that version of the engine. The AWD Escalade stared production in January 2006.

So in my opinion, the L92 with AFM hardware but not active in the tune would be limited to the 2007 Yukon Denalis made in December 2005 and maybe into January or February 2006, and probably just the AWD versions at that.

So besides the build date which we are not 100% sure of, it's the valley cover that will let you know for sure. Remember, even those with the hardware did not have AFM running in the tune. So none of the 6.2s had a working AFM system until the introduction of the L94 for the 2010 model year.

 

[R3cord303]

This is the best explanation I've ever seen and now fully understand it myself! Thanks Allen!



I often write that those motors were made before April 2006 but I'm now pretty sure it was April 2005. So these would be the very earliest trucks, the Tahoes and Yukons entered production first in December 2005 and the longer ones began production in March. I doubt the longer ones would have that version of the engine. The AWD Escalade stared production in January 2006.

So in my opinion, the L92 with AFM hardware but not active in the tune would be limited to the 2007 Yukon Denalis made in December 2005 and maybe into January or February 2006, and probably just the AWD versions at that.

So besides the build date which we are not 100% sure of, it's the valley cover that will let you know for sure. Remember, even those with the hardware did not have AFM running in the tune. So none of the 6.2s had a working AFM system until the introduction of the L94 for the 2010 model year.

sure thing homie. I kept trying to tell my grandad who owned my 07 before me about why installing a new valve cover would curb his oil consumption and he didn’t believe me until i slapped the valve cover on and reported back.

 

[R3cord303]

@swathdiver i should also add that the afm deflector shield thingy that goes on the oil return in the oil pan- that helps reduce oil consumption by directing the oil spray into the oil contained in the sump, producing less oil vapor, which gets sucked up by the pcv. Thats my understanding anyway.

 

[MLRTYME]

This is the best explanation I've ever seen and now fully understand it myself! Thanks Allen!



I often write that those motors were made before April 2006 but I'm now pretty sure it was April 2005. So these would be the very earliest trucks, the Tahoes and Yukons entered production first in December 2005 and the longer ones began production in March. I doubt the longer ones would have that version of the engine. The AWD Escalade stared production in January 2006.

So in my opinion, the L92 with AFM hardware but not active in the tune would be limited to the 2007 Yukon Denalis made in December 2005 and maybe into January or February 2006, and probably just the AWD versions at that.

So besides the build date which we are not 100% sure of, it's the valley cover that will let you know for sure. Remember, even those with the hardware did not have AFM running in the tune. So none of the 6.2s had a working AFM system until the introduction of the L94 for the 2010 model year.

Thanks for the info. Very helpful!