Jonblarc7

My problem, 08 denali sierra 6.2 with 150K miles

I started a thread 3 months ago about my truck knocking going down the highway. It turn out I have no low oil sensor and I was low on oil. It wasn't time for a change and I pull about 7000lb. boat during the summer and I used 4 quarts of oil. I thought was really high so I changed it and put 6 quarts in it and said I'll keep an eye on it and will see how bad it's burns oil while it's not boating season.

So 3 months later and about 4400 miles I decided to check it today. And guess what, It only had oil on just the tip of the dip stick. It's not leaking any, I park in the same two spots every day and there is no oil on the ground.

I'm going to change it tonight and measure how much I get out of it.



Should I do a compression check? I guess bad compression will burn oil but I don't see any smoke. But my exhaust is cut off above the axle so I can't really see the tip unless I'm laying on the ground.

Any thing else I can do to see if it's consuming oil and not leaking.

No DOD or AMF on my truck

FFDP

iTrader: (2)

Gm says that 1 quart per 3,000 miles is normal and really it is technically.

You made it 4,400 miles with no heavy driving and got to that quart mark, so really nothing is wrong in a way. Plus it's well over 100k miles.

The first 2 years of the 5.3/6.2 are known for eating more oil than the later engines. There was some sort of issue or maybe even a TSB on the valve covers because of the breather, causing more oil to be used.

Clearly you know it's eating the oil if no oil spots are on the ground and no leaks present, oil can't just vanish into thin air. I bet compression and a leak down test will still say the engine is just fine. Oil getting past the rings, valve seals and bad PVC function can all lead to oil consumption but as of right now it's eating oil at such a slow rate you'd never know exactly what is the cause.

Jonblarc7

No I made it 4,000 miles and don't have any oil on my dip stick but just a little on the very tip of the dip stick. So I'm betting it used 4 quarts out of the 6 in 4,000 miles. I'll post a pic of how much drains out tonight.

Jonblarc7

What is a "TSB on the valve covers"

I'm not running a catch can but I'm not opposed to running one.

For now I'm just running headers not cats and custom tune.

FFDP

iTrader: (2)

Did you actually have to add 4 quarts this time though?

If it's barely on the bottom of the stick that only 1.5-2 quarts low. I know it's burning more than avg but doubtful it's 4 quarts low again.

I think of it this way, check the oil more often and if all that's wrong with it is a little oil burning you are getting off pretty easy lol. If it only costs you $5 per 3,000 miles to run it, that is pretty damn cheap. A full rebuild would be 300x more money.

ezdaar

iTrader: (1)

GM saying oil consumption is normal, is just a way to cover for their **** tolerances in the LS engines.

A Properly built engine doesn't consume ANY oil.
As awesome as these LS engines are, they was surly built poorly.

FFDP

iTrader: (2)

What about the oil on the cylinder walls as the pistons go up a down, that burns off. All motors use oil, they couldn't run if they didn't. It's just that a good built motor uses such little amounts that it's not something you could really measure which I totally agree with.

vettelovralexand

All engines lose or burn oil from 3 places: power cylinder, valve stem seals, and crankcase ventilation. That is from a properly designed engine with everything working as designed. Most references say that oil consumption rises as a function of engine power. So, the GM spec is probably from a highly loaded "working" engine with hot oil. If you are working your engine, you too should expect oil consumption to fall closer to their specification, but really you shouldn't be above their number.

Jonblarc7

I got what your saying now. I haven't add any yet because I'm at work.

I'll go home tonight and drain it and see how much comes out. I cheap enough and peace of mind just to drain it than just look at the dip stick.

The reason I checked it is, when it sits for a few hours and I crank it. There is a pretty good rattle sound and it sounds like it's coming from the valve train. It goes away within a sec of it running. I was doing this last time the oil got this low.

Jonblarc7

Well this is how much oil was left after 4000 miles. So I guess maybe 3 quarts were gone.

Not as bad as I pictured in my head.