Oil consumption test

urbancowboy · February 21, 2015

My 2011 Gmc 1500 Slt cc 5.3 Aluminum black, 67,500 kms on it now, (42,000 miles), always used Mobil Synthetic was consuming oil so dealer had a oil consumption test done. First time fell below guidelines and had flow preventer mod done, well truck was still consuming oil after this, so another test was done. Truck was brought in several times and oil level was checked up until the last time at 7700 kms 30% left on oil life monitor. Truck was consuming oil all the time test done, at 3200 kms oil was checked dealer said it calls with in the guidlines no issues but at 7700 kms the oil level was barely touching the dipstick. Dealer says again no issues, are you kidding me? The engine is consuming oil, barely on dipstick says again at 3200 kms its within guidelines. Ok but how about at the end its barely on the dipstick how many litres is that down? Obviously the engine is drinking oil. Called Gm to complain as they called the service manager and he tells them also it falls within the guidelines? at 3200 kms oil is down, at 7700 kms its really down but its within guidelines. I guess if no oil on the dipstick is normal? I'm not very impressed with Gm, what joke as they know its well documented how many Tsb's are there out there on this problem. How many litres is it down if its just barely touching the dipstick, thats not normal I don't care what Gm says. I have and Acura Tl change the oil when the monitor says 15% never has used a drop oil. Not very happy and I know I'm not the only one with this same problem.

yz2009 · February 21, 2015

From what I've read the GM says a quart of oil used for every 2000miles (edit) is considered acceptable and they won't do anything to help you out.

I feel for you I would be pissed if I had a brand new truck using that much oil

urbancowboy · February 21, 2015

but how may quarts tor litres has it used to the bottom of the dip stik?

yz2009 · February 21, 2015

im not sure. i know on my 2004 5.3 from the bottom of the acceptable oil level hash marks to the top of the acceptable oil level hash marks is almost exactly 1 quart

BLACK DEATH · February 22, 2015

My 99 transam with 88k miles does the same thing, consumes oil.

MaverickZ71 · February 23, 2015

My 2011 Gmc 1500 Slt cc 5.3 Aluminum black, 67,500 kms on it now, (42,000 miles), always used Mobil Synthetic was consuming oil so dealer had a oil consumption test done. First time fell below guidelines and had flow preventer mod done, well truck was still consuming oil after this, so another test was done. Truck was brought in several times and oil level was checked up until the last time at 7700 kms 30% left on oil life monitor. Truck was consuming oil all the time test done, at 3200 kms oil was checked dealer said it calls with in the guidlines no issues but at 7700 kms the oil level was barely touching the dipstick. Dealer says again no issues, are you kidding me? The engine is consuming oil, barely on dipstick says again at 3200 kms its within guidelines. Ok but how about at the end its barely on the dipstick how many litres is that down? Obviously the engine is drinking oil. Called Gm to complain as they called the service manager and he tells them also it falls within the guidelines? at 3200 kms oil is down, at 7700 kms its really down but its within guidelines. I guess if no oil on the dipstick is normal? I'm not very impressed with Gm, what joke as they know its well documented how many Tsb's are there out there on this problem. How many litres is it down if its just barely touching the dipstick, thats not normal I don't care what Gm says. I have and Acura Tl change the oil when the monitor says 15% never has used a drop oil. Not very happy and I know I'm not the only one with this same problem.

There have to be thousands, if not millions, of GMT-900 (2007-2013 Sierra and Silverado 1500's) trucks out there with this AFM oil usage problem. (There should be a class action suit over this!) In this forum, we have seen this problem proceed from year to year. Supposedly GM did a oilpan deflector and revised valve cover PCV orifice that was implemented at the factory sometime during the '11 model year. My '09 has had those revised parts installed and the piston rings 'cleaned', but it did not make any difference. Now we are seeing the 2011/2012/2013 model years have this problem when it was supposed cured during 2011. The main thing is to pursue getting new pistons/rings from GM under warranty. The dealers have been known to drag their feet and say there is no problem until you are out of warranty. If they will not do new pistons and rings for you, have your AFM function turned off immediately via a Range module or new PCM tune. Then run AutoRx in your engine oil to clean your rings and Chevron Techron Fuel System Cleaner in your fuel tank to clean your oil-fouled spark plugs. Good luck and keep us posted.

GSD · May 19, 2015

I have a 2011 Sierra. Before I had 5000 miles on the truck, I was informed of the oil consumption issue. Since that time I have forced the truck to run on 8 cylinders by putting the transmission in "M" and forcing it to stay in 5th gear. AFM is disabled in 5th gear. Difference in mileage is negligible. Truck runs great, like a full-size truck should without the shuttering when going from 4 to 8 cylinders. No oil consumption issues to date. Have been a GM owner for many years and very satisfied with the truck otherwise, but this will be the last.