I had to add 3 quarts of oil to my truck...

[Twodose]

I have a 2011 GMC Sierra 1500 SLT, I started using synthetic amsoil about 2 years ago, I just checked the oil and had to add 3 quarts of oil, it takes 6 quarts for an oil change with the filter, the check engine light did not come on, could this have possibly done some damage to the engine?

[CamGTP]

The check engine light will never come on. And those trucks do not have low oil level sensors either. It's pretty much up to you to find out the oil level and keep track of it.

 

It didn't do any damage if you never lost oil pressure. There would be a warning for that. I've seen trucks come in with 2 quarts in the system and they still ran fine. From now on you will want to track your oil level every 500 miles or so to see if this is starting to become a problem.

 

Could be a AFM/DoD issue. Oil getting past the valve seals or come past the piston rings. A easy check would be to pull the spark plugs and see if any of them are oil covered or have the looks of oil burning. Could also try an oil additive to see if that helps with oil burning, I know Liqui Moly makes a few oil additives that they say help with oil consumption and extra lubrication for metal parts.

[Twodose]

The first thing I did when I noticed it was low was check the oil pressure and it was fine, I never had a light or any warning for low oil pressure.

About a year ago I made this post I made on a different forum:

 

https://www.truckforums.com/forum/chevy-silverado-gmc-sierra-forum-11/change-full-synthetic-now-burning-oil-22886/

4419 miles used 2.5 quarts of oil. < this was a year ago.

4872 miles used 3 quarts of oil < this was from last oil change to now and there is 29% life left on the oil monitor.

I only put about 5k miles a year on the truck.

Before switching to full synthetic, this truck never used a drop of oil.

[Jworks]

I have 2 inputs on this. 

(1)  Years back, in the late 70s - early 80s Amsoil was being promoted by people I knew that got in on the "Amway-type" sales structure.  I had a  beautiful baby blue, 1980 T-top Thunderbird I bought and put Amsoil in the 302 engine.  It was suppose to last 25,000 miles.  After a lot of miles, but way less than 25k, I looked at the oil and it was black, very black, and down a quart or so.  I was shocked.  I pulled a small amount out and had its content tested.  That was 41 years ago so I've forgotten the report details but the one thing I remember that stuck out was the higher than normal level of chromium in the oil (rings) and the much higher level of silicon (dirt/grit).  I pulled it out and went to regular oil.  I got to thinking, the oil itself may have been good for 25k miles, but the grit and chromium was just too high.  I don't let any brand stay in there for 25k miles anymore.  Amsoil may be much different and better today, I don't know.  Engines are a whole lot different, and better, than the old 302 of 1980. 

 

(2)  I had a 4.3 in a 94 GMC pickup I bought in '96 with 55k miles on it.  I used regular oil till it began using a little bit of oil (but not much).  I recalled what a mechanic friend of mine told me before, so I added STP to my next oil change.  He recommended it in every oil change.  I drove that truck for 19 years and never touched the engine -- all that time using STP in with each oil change.  It had 484k miles on it when I sold it.  Yes, someone bought it with that many miles.  All that time I used STP and conventional oil (Castrol).  But that was a different era engine and not like the engines today. Today, I do use synthetic in my 2011 GMC.  So, I kind of agree with CamGTP's recommendation about trying an additive (like STP) that definitely did stop oil consumption for me.  I know the mention of STP can open a whole new discussion amongst motor enthusiasts.  But it worked for me.  I "think" newer engines probably have higher, tighter specs so I don't know how it will work in newer engines I don't know.  But it certainly worked for me then and did a super job.

 

By the way, I have a 2011 GMC also.  5.3 engine.  I am just letting the dealership change my oil now because of my age and don't want to get under there anymore.  They're using the Dexos full synthetic.  136k miles, no consumption.

Edited October 25, 2021 by Jworks

[KARNUT]

16 minutes ago, Twodose said:

The first thing I did when I noticed it was low was check the oil pressure and it was fine, I never had a light or any warning for low oil pressure.

About a year ago I made this post I made on a different forum:

 

https://www.truckforums.com/forum/chevy-silverado-gmc-sierra-forum-11/change-full-synthetic-now-burning-oil-22886/

4419 miles used 2.5 quarts of oil. < this was a year ago.

4872 miles used 3 quarts of oil < this was from last oil change to now and there is 29% life left on the oil monitor.

I only put about 5k miles a year on the truck.

Before switching to full synthetic, this truck never used a drop of oil.

I’ve had two oil users from new. One qt every 2500 miles. Surprisingly one was a Ford truck the other was a Z-28. After driving the Ford 20K miles I put a super charger on it no change. I did the oil dance no change. They both went about 130k before I sold them. Of course non had cylinder deactivation which adds another wrinkle. I had another hot rod truck that used more oil. 14 years later still going. 

[KARNUT]

4 minutes ago, Jworks said:

I have 2 inputs on this. 

(1)  Years back, in the late 70s - early 80s Amsoil was being promoted by people I knew that got in on the "Amway-type" sales structure.  I had a  beautiful baby blue, 1980 T-top Thunderbird I bought and put Amsoil in the 302 engine.  It was suppose to last 25,000 miles.  After a lot of miles, but way less than 25k, I looked at the oil and it was black, very black, and down a quart or so.  I was shocked.  I pulled a small amount out and had its content tested.  That was 41 years ago so I've forgotten the report details but the one thing I remember that stuck out was the higher than normal level of chromium in the oil (rings) and the much higher level of silicon (dirt/grit).  I pulled it out and went to regular oil.  I got to thinking, the oil itself may have been good for 25k miles, but the grit and chromium was just too high.  I don't let any brand stay in there for 25k miles anymore.  Amsoil may be much different and better today, I don't know.  Engines are a whole lot different, and better, than the old 302 of 1980. 

 

(2)  I had a 4.3 in a 94 GMC pickup I bought in '96 with 55k miles on it.  I used regular oil till it began using a little bit of oil (but not much).  I recalled what a mechanic friend of mine told me before, so I added STP to my next oil change.  He recommended it in every oil change.  I drove that truck for 19 years and never touched the engine -- all that time using STP in with each oil change.  It had 484k miles on it when I sold it.  Yes, someone bought it with that many miles.  All that time I used STP and conventional oil (Castrol).  But that was a different era engine and not like the engines today. Today, I do use synthetic in my 2011 GMC.  So, I kind of agree with CamGTP's recommendation about trying an additive (like STP) that definitely did stop oil consumption for me.  I know the mention of STP can open a whole new discussion amongst motor enthusiasts.  But it worked for me.  I "think" newer engines probably have higher, tighter specs so I don't know how it will work in newer engines I don't know.  But it certainly worked for me then and did a super job.

In the early days of Amsoil they recommended using their flush before changing to their oil. Something we all did switching from conventional to synthetic. Before synthetics we used slick 50 and STP. Both claimed to help with cold starts. Another benefit with synthetic.

[Black02Silverado]

I don't think you have any damage.  AFM/DoD as I understand can lead to issue with oil consumption.  One thing you can try is go back to the oil you used previously since you said it didn't use it.  See what happens.  There are several factors as CamGTP pointed out that can lead to oil consumption. 

 

Also with the AFM/DoD what I have read is if you do more hwy driving the issue is worse for consumption because the system is active and shuts down cylinders causing the consumption for some reason.  But those that do a lot of city driving where it isn't in play they don't have any consumption issues. Again, this is from what I have read others have experienced.

 

How many miles total are on the truck?

 

[Twodose]

I bought Amsoil Engine and Transmission Flush but haven't used it yet, I will try on this oil change.

[Twodose]

6 minutes ago, Black02Silverado said:

How many miles total are on the truck?

83,600.

 

Edited October 25, 2021 by Twodose
edit

[Twodose]

Do the Range afm/dfm disabler's work?

I never thought the 8-6-4 was a good idea, my father 40 years ago bought a new cadillac that had that when it first came out, they had nothing but problems with it. 

[newdude]

Its not from the oil.  Its not from AFM either.  The AFM system doesn't cause oil consumption.    

 

I would do an oil consumption test.  Change it, 6 fresh quarts and a filter back in.  Drive it 2000mi while monitoring the dipstick over that time.  I would then drain the oil and measure how much you drain out at that 2000mi mark. 

 

If more than 1 quart is missing in that timeframe, start with a new driver's side valve cover see if it improves it.  If you see no improvement in consumption, you can try GM top engine cleaner soak of the cylinders.  If that doesn't reduce it?  Pistons and rings.   

Edited October 25, 2021 by newdude

[WeGone]

My 2021 6.2 has used 1qt in 3300 miles total mile on it now. I did my first change was at 1500. I always run in 9th gear around town (so no cylinder de-activation) and only go to 10th on the highway over 65mph.

Edited October 25, 2021 by WeGone

[newdude]

1 minute ago, WeGone said:

My 2021 6.2 has used 1qt in 3300 miles. I did my first change was at 1500. I always run in 9th gear around town (so no cylinder de-activation) and only go to 10th on the highway over 65mph.

 

 

Normal for a new engine to potentially consume during break-in.  Rings are seating in that period.  Also, your 5.3 and OP's 5.3 are quite different engines.  

[WeGone]

My thoughts also.

[Twodose]

8 minutes ago, newdude said:

Its not from the oil.  Its not from AFM either.  The AFM system doesn't cause oil consumption.    

 

I would do an oil consumption test.  Change it, 6 fresh quarts and a filter back in.  Drive it 2000mi while monitoring the dipstick over that time.  I would then drain the oil and measure how much you drain out at that 2000mi mark. 

 

If more than 1 quart is missing in that timeframe, start with a new driver's side valve cover see if it improves it.  If you see no improvement in consumption, you can try GM top engine cleaner soak of the cylinders.  If that doesn't reduce it?  Pistons and rings.   

I appreciate the input, but I would rather buy a new truck, If I could find one...just to probably have the same problems again.... lol.