Is Your Gmt-900 Truck Or Suv Using Oil

[arz71]

My Gmc doesn't burn oil because I turned off the stupid AFM

 

I bet the EPA bean counters will pass regulations in the not so distant future making this illegal and/or unable to turn off.

[elvis56]

My 2008 Tahoe, 5.3 Flexfuel, AFM, 4 spd, will lose about a liter by the 5000km mark. I check it every week to be safe. Its important to keep in mind that if you run your vehicle down to 0 % on the oil life monitor, you could potentially run through 10000kms or more. Im not condoning the oil consumption issue, just reminding folks that if you have the AFM, its important to do regular checks at the dipstick. I also have a 2011 GMC Sierra 1500, 5.3, 6 spd, no AFM... got 100000kms on that as well and doesnt burn a drop.

Forgot to mention, I used 100% synthetic in the Tahoe, and also switched to semi-synth and dino and didnt see much of a difference in consumption between them.

[Cowpie]

I have 6000 miles on my present oil change, at 23% on the OLM, and I it has used about 1/4 of a quart. Of that 8 oz that it has "used", 6 oz of it ended up in the PCV oil catch can on the engine. So the engine has only "used" about 2 oz in 6000 miles. Not bad. AFM turned off.

 

After factory fill oil change at 1190 miles on odometer, it has been on Schaeffer 9000 5w30 synthetic (no, not on the dexos1 "approved" list). Currently at 22342 miles.

Edited December 23, 2014 by Cowpie

[rws262]

How can I turn off the AFM?

[RyanbabZ71]

How can I turn off the AFM?

Range device or tune

 

 

Ryan

[greg74]

AFM seemed like a good idea at the time but from what I've read on here, its one of the worst things GM ever did to their trucks. Very minimal fuel mileage gains and premature engine wear. I have a 99 Silverado Z71 with 190K miles on it and it doesn't use a drop of oil. Neither does my 2004 Grand Am with 149K miles on it. All these newer trucks with 30K or less miles on them using oil, just makes me shake my head. Adding oil is what you do to an old, tired engine. Anything with less than 100K miles on it should never need any oil to be added unless you abuse the hell out of it. Makes me never want to buy any used GM truck with AFM.

[greg74]

 

I bet the EPA bean counters will pass regulations in the not so distant future making this illegal and/or unable to turn off.

I wish they would just quit worrying about fuel economy. All these damn tree-huggers too concerned about a couple mpg, go save a whale or something. In reality people buy small cars for fuel economy and trucks for hauling and towing. No, you wouldn't want your truck to get 1970's fuel economy numbers that might barely reach 10mpg. It would be much simpler if GM didn't make all their gas engines with AFM. It should be an option, not standard. Then after a couple years when they realized nobody wanted it, they would no longer waste their time on it. Sad part is, they probably spent billions developing something that at the very best is annoying and at worst does very little if anything to improve fuel economy and makes the vehicle run worse and is bad for your internal engine components.

[Cowpie]

I am not so concerned about the busy bodies worrying about fuel economy, it is the hit and miss poor marksmanship the OEM's use to try to get there. They continue to play little games with the motors instead of just taking a quantum leap and building a motor that will have excellent performance and great fuel economy to. It can be done.

 

We all know that ethanol negatively affects fuel economy in our vehicles we have now. But there are motor designs that have gone thru extensive testing that use E85 only and blow the socks off of the motors we use now in both power and fuel economy.

 

This lame cylinder shutdown stuff is about as goofy as it comes in tackling the mpg game. It is not impractical to have motors in our vehicles that exceed the proposed CAFE standards and provide decent performance. Engine designers have most of the nuances to engine design to do this already worked out. Cummins, Ricardo, and other engine designers have gasoline/ethanol fueled motors right now that could knock the socks off of anything being put in a auto or pickup now, and compete favorably even with the diesel motors.

[Stex]

Oil burn continues on my 09 with AFM off (catch can installed) and this is with the PCV update and valve cover update. We did not do the ring/piston part of update.

 

Now at 70,000 getting the lifter clatter on heat sink starts on cold days. Lifter job on the 5.3 is a lot of man hours and truck will be gone if gets worse. Early 900s have the AFM lifter problem. Why did I not buy a 6.2 in 09???

 

Any one got a 900 SLT 6.2 they want to sell? The'14-'15sl 6.2 now have AFM.

Edited March 9, 2015 by STex

[arz71]

Oil burn continues on my 09 with AFM off (catch can installed) and this is with the PCV update and valve cover update. We did not do the ring/piston part of update.

 

Now at 70,000 getting the lifter clatter on heat sink starts on cold days. Lifter job on the 5.3 is a lot of man hours and truck will be gone if gets worse. Early 900s have the AFM lifter problem. Why did I not buy a 6.2 in 09???

 

Any one got a 900 SLT 6.2 they want to sell? The'14-'15sl 6.2 now have AFM.

 

What exactly if the ring/piston update a new design???

[Stex]

 

What exactly if the ring/piston update a new design???

No not new, it is the normal ring/piston change out for the oil burners covered on this thread.

[arz71]

No not new, it is the normal ring/piston change out for the oil burners covered on this thread.

Makes sense, does this go back to the 'every bore' is the same in the blocks and the same piston/ring set for everyone where they are not really matched?

[Jsdirt]

Not sure what GM does ... but it obviously is NOT working ...

 

We have been building internal combustion engines for well over 100 years now. You'd think we'd have learned something along the way???

 

If I ever sent out an engine I rebuilt that smoked and used oil like alot of these new trucks, I'd get it back - and the customer would NOT be happy. I'd probably lose alot of business as word spread. How does GM still manage to sell trucks? Guess it's the same crowd buying that voted the past 8 years ... Head in the sand, oblivious to the world around them. I don't get it ...

Edited March 19, 2015 by Jsdirt

[HateCarpetGuy]

Well, after 380,000+ miles on my 2008 CC 5.3 (with a pile of receipts for keeping oil in engine), I'm done with Government Motors. Sent truck to auction and bought a Ford. However, he GM did fetch $7,500 at auction but only because it had been well-maintained, would crank and run smooth, decent tires, etc. New owner has no idea that AFM is OFF, valve cover/PCV replaced, seat belt dinger OFF, auto-door locks OFF, computer re-programmed in lieu of chip, AND that truck started to consume oil again.......I give up. But I do totally agree with Sr. Enthusiast that, geez Louise, how long has GM been building engines? and you struggle with keeping oil in crankcase???

 

Never again will I be a GM owner. You boys have fun, hatecarpetguy signing OFF for last time.

[mrmjbenn]

2012 Sierra 5.3L not sure about block, uses about 1 qt by 3k after oil change, sometimes more. Started consumption test at dealership first 2k no change so I dropped it. Had #7 plug go bad, didn't think to ask the mech about the plug, I didn't think it was connected now it makes me wonder.I use pensoil platnum pure synthetic 5w-30. Oh yea about 55k miles. If there is something I should do or can do to eliminate this problem please let me know. THanks