Oil gone

Hello. I have a 2007 denali xl. Recently the add oil light came on. Thought that was a little odd. Added oil as it had none. About 2 weeks or so same thing again. Its not leaking oil but its obviously sucking it up somewhere. Sometimes not everytime when I start the truck there is a white cloud of smoke. Only when I start it and it disappears. Does not continue when I drive. Help!! Thanks,

“Adding oil as it had none”. That sounds scary, although even if no oil is shown on the distick, you will still have about 2 quarts left in the crankcase.

If you were burning this much oil, the exhaust would be blue, so it’s going somewhere else as well.

This is not something you can ignore; please see a good mechanic (not a tire or muffler chain) to analyze the engine. There might be a cheap fix. Also check is there is any oil on your drveway after letting the engine run for 20 minutes or so?

I’ll let the experts comment on the white smoke.

However, I need to ask two questions. First, how much oil did you have to add each time? Second, does your manual say this light is for low oil pressure or for a low oil level? If it’s the former, as I suspect, you need to be aware that you caused permanent damage to your engine by letting the oil level get that low, doubly so if you didn’t stop the car immediately when it came on. It seems that you might not understand that keeping a sufficient amount of oil is critical to your engine’s health.

No oil on ground. Light says low oil add oil.

From afar, my best guess is that the engine has a breached head gasket.
That could explain both the white smoke and the drastic drop in oil level.

The OP needs to take the vehicle to a competent mechanic for a compression leak-down test, and to ascertain whether combustion byproducts are present in the cooling system. This is something that cannot be ignored if the OP intends to keep the vehicle, rather than junking it in the near future.

I emphatically agree with those that suggest you get this to a shop ASAP and get it diagnosed. If VDC is right, and he often is, failure to get the problem addressed could result in the engine being destroyed. Coolant being drawn into the engine’s cylinder through a breeched head gasket can be destructive, and constantly running low on oil runs its own risks.

Was this a red light that looks like an oil can with a spout?
Or does it say “add oil” spelled out?

I would agree that someone should look at the car so that the symptoms can be more effectively addressed. It could need a new PCV valve or it could be using some oil now. Just as a comment, terminologies used sometimes lead us astray. When someone says it “had no oil”, that can mean it was down a quart all the way to the engine seized because of literally no oil. Someone needs to actually see what light went on and question how much oil was put in, where the level is, when the oil was changed, etc. Same thing for terminology like “engine cranks but does not turn over”. Its detective work that can best be done on site.

Find a local reputable independent shop that has up to date service information and technical bulletins from General Motors. There is an updated left valve cover to address oil consumption issues.

I have a 06 GMC 1500 truck with the 5.3L V8. This is most likely the same engine you have. When the add oil light comes on its 2 QT’s low. @asemaster can you tell us more about this updated valve cover? I just changed my spark plugs and the left side had signs of oil burning. Right side were fine. Thanks.

@oldbodyman‌ I’m at home now, but I seem to remember a TSB about the 5.3 engine that included an updated valve cover for the driver’s side that improved or corrected PCV flow to reduce engine oil consumption through the PCV system.

The oil – however it is getting there – is probably being burned in the engine. I expect the cat is preventing the clouds of blue smoke you’d normally see in pre-cat days. B/c you are seeing an unusual amount of white smoke, my first suspicious would be a head gasket on the fritz. Especially true if the engine has recently overheated.

Other possibilities into the engine to consider are the PCV path and faulty valve stem seals.

Thanks @asemaster. I hope what I found helps the OP. I did some searching on line for this TSB. What I found is this new valve cover is needed along with a AFM deflector shield and soaking of pistons and rings. I am going to see a friend at dealer today to see what the parts cost and what they charge to do this. Can you explain what AFM is and how it works?

AFM Active Fuel Management
DOD Displacement on Demand
MDS Multiple Displacement System
V8-6-4 Remember that one?

All are systems designed to improve fuel economy by disabling portions of the valve train to reduce the number of cylinders in operation.

“V8-6-4 Remember that one?”

Unfortunately, I do.
When I got a summer job as a limo driver, because I was the newbie, I was the one who got the Fleetwood Limo with the V-8-6-4 engine. The owner of the limo company said, “As long as you warm it up for at least 1/2 hour before driving it, it should be okay”. That was in 90 degree temperatures!

As it turned out, nothing really helped to make things predictable when you tried to accelerate.
Sometimes, it seemed normal.
At other times, it accelerated like an old VW Beetle, and sometimes it had the charming habit of just stalling when you hit the gas. Trying to merge onto an interstate highway while carrying 5 passengers + luggage was…exciting…to say the least.

The other drivers nicknamed it the V-8-6-4-2-0.

If you are not loosing coolant and no oil is showing up in the coolant, then the white smoke could be simply condensation in the exhaust system as the vehicle cools down, especially overnight in a humid environment.

Or the white smoke could actually be a light gray smoke instead and it could be due to the TSB above or bad valve seals or it could be due to sludge build up around the oil drain back holes in the head, particularly the rear drain back hole.

Disable AFM and see if problem persists? I didn’t know that they had AFM as far back as MY2007…but I do know it works by collapsing the lifters, and can consume oil if not A-OK.

Twenty-two pages of AFM engine problems: