Excessive Oil Consumption-2007 Suburban

marnisampair · March 25, 2009

I have been going over all these discussion about excessive oil consumption lately, as I have a 2007 Suburban with a 5.3 that sucks 1 quart every thousand miles.

GM has changed their oil consumption guidelines to allow for 1 quart every 2,000.

Does anyone find this completely ludicrous? Why is any oil consumption ok? My dad comes from a different generation, but he said that is wrong.

What are the long term affects on a truck that consumes as much as mine does?

BTW-I know about ALL the TSB's, my truck has had 4 major repairs and it still does it.

Thanks!

99silverado1500 · March 25, 2009

I think thats a lot of oil for 1000 miles. I go through maybe a quart tops every 3000 miles, and thats TOPS, its usually .5 quart

Draenor · March 25, 2009

Sure you don't have any leaks? Are you getting any blue smoke out the exhaust? Pulled the plugs to inspect?

I agree that this is excesive.

gave20 · March 25, 2009

If it's within their consumption guidelines than it's not excessive and they won't touch it. If it's not, then they should fix it.

pennzoil29 · March 25, 2009

That seems like a lot of oil. My '99 5.7 uses about 1/2 of a quart for every 3K, and it has 175+K on the clock.

66nova · March 25, 2009

I would agree with the masses here. That sounds like too much oil.

Oil consumption is natural due to the nature of how the cylinders are coated. There will be some oil get burned due to combustion. I had a teacher in one of my engine classes tell me, "I would never buy a car that didn't burn some oil. It's not getting properly lubricated then". He was kind of a "tool", but his point is solid. This true in all engines, but a quart every 1000. I would have that in the dealership.

Like said earlier...Any blue smoke? Any leaks? Look under it to make sure the bottom is not coated with oil.

Good luck!

ujtruck · March 26, 2009

1 quart every thousand miles ? that is way too much oil burning or oil going somewhere... time to see a good tech.

superjim · March 26, 2009

One quart per 1000 miles...thats WAY too much.

if still under warranty...it would be living at the dealers till they FIXED IT RIGHT.

C & A s Dad · March 26, 2009

Marni, I would agree this is too much.

I would ask one thing and I am sure it has been checked.

By any chance, you or someone working on your truck has not replaced the PCV valve have they? If so, and they used an old style check valve type instead of the fixed orfice type, this could be part of your problem.

Pull the PCV valve (in the top of the driver's side valve cover at the back.) If it rattles when you shake it, it is wrong for your truck. It should have a small hole in the bottom with no valving inside.

From there, I would be looking for leaks. It would be very rare to see one of these engines buring this much oil.

Just a thought.

fbachman · March 26, 2009

GM has changed their oil consumption guidelines to allow for 1 quart every 2,000.

Thanks!

That's interesting/disheartening.

If I were to STRICTLY abide by the oil change interval as indicated by the DIC, based on my extrapolations as to what the DIC thinks the remaining oil life is at the time I actually CHANGE it, it would seem that the DIC will allow you to (readily) go 5000-6000 miles before ringing up an oil change request.

Given that, it seems like an engine that is consuming oil on the HIGH side of the 1qt/2000 mile guideline, you could be down between 2.5qts and 3qts when ya change if you follow the DIC. I believe these things hold on the order of 5qts?

That could mean that at the time you do a DIC commanded oil change, you are down to 40%-50% oil capacity remaining?

Seems bizzarre to me......

Toadster · March 26, 2009

have you checked your PCV valve?

this is a common issue on many cars where the PCV sticks open - sucking OIL out of the engine....

DBVille · March 26, 2009

I have been going over all these discussion about excessive oil consumption lately, as I have a 2007 Suburban with a 5.3 that sucks 1 quart every thousand miles.

GM has changed their oil consumption guidelines to allow for 1 quart every 2,000.

Does anyone find this completely ludicrous? Why is any oil consumption ok? My dad comes from a different generation, but he said that is wrong.

What are the long term affects on a truck that consumes as much as mine does?

BTW-I know about ALL the TSB's, my truck has had 4 major repairs and it still does it.

Thanks!

If you understand the workings of an engine, you will understand that oil will be consumed. How much varies, but it will burn some.

Long term depends on why its burning oil. It could be maintenance items like PCV, in which case this doesn't apply. 1 Qt/1,000 miles is the old standard, but, realistically, every 5,000+ miles is pretty much common. If you damaged the engine by over heating or running low on oil, it will probably continue to get worse. At some point, assuming a piston doesn't seize (it probably won't), the plugs will foul out and require replacement every couple hundred miles, and (assuming its leaking rings), power will be reduced until it barely runs. Smoke screens out the tailpipe might also get frequent visits by the local police, and if you have emissions, you will start to fail those inspections.

But, if it is just clearances in the motor, it may run like that forever. It might foul plugs a little more often, but that would be about it.

Grumpy Aero Guy:

GM used to say 1 qt/1,000 miles. But, you really should be checking your oil level every 2,000 miles or so, or more often if it uses oil. The Oil Life Indicator is not meant to replace the dipstick!!

fbachman · March 26, 2009

I have been going over all these discussion about excessive oil consumption lately, as I have a 2007 Suburban with a 5.3 that sucks 1 quart every thousand miles.

GM has changed their oil consumption guidelines to allow for 1 quart every 2,000.

Does anyone find this completely ludicrous? Why is any oil consumption ok? My dad comes from a different generation, but he said that is wrong.

What are the long term affects on a truck that consumes as much as mine does?

BTW-I know about ALL the TSB's, my truck has had 4 major repairs and it still does it.

Thanks!

If you understand the workings of an engine, you will understand that oil will be consumed. How much varies, but it will burn some.

Long term depends on why its burning oil. It could be maintenance items like PCV, in which case this doesn't apply. 1 Qt/1,000 miles is the old standard, but, realistically, every 5,000+ miles is pretty much common. If you damaged the engine by over heating or running low on oil, it will probably continue to get worse. At some point, assuming a piston doesn't seize (it probably won't), the plugs will foul out and require replacement every couple hundred miles, and (assuming its leaking rings), power will be reduced until it barely runs. Smoke screens out the tailpipe might also get frequent visits by the local police, and if you have emissions, you will start to fail those inspections.

But, if it is just clearances in the motor, it may run like that forever. It might foul plugs a little more often, but that would be about it.

Grumpy Aero Guy:

GM used to say 1 qt/1,000 miles. But, you really should be checking your oil level every 2,000 miles or so, or more often if it uses oil. The Oil Life Indicator is not meant to replace the dipstick!!

Trust me, I DO.... I tend to change the oil much more frequently than the DIC would want me to and I keep an eye on it.

Still 2q/1000miles...... maaaan....

marnisampair · March 27, 2009

I have been going over all these discussion about excessive oil consumption lately, as I have a 2007 Suburban with a 5.3 that sucks 1 quart every thousand miles.

GM has changed their oil consumption guidelines to allow for 1 quart every 2,000.

Does anyone find this completely ludicrous? Why is any oil consumption ok? My dad comes from a different generation, but he said that is wrong.

What are the long term affects on a truck that consumes as much as mine does?

BTW-I know about ALL the TSB's, my truck has had 4 major repairs and it still does it.

Thanks!

If you understand the workings of an engine, you will understand that oil will be consumed. How much varies, but it will burn some.

Long term depends on why its burning oil. It could be maintenance items like PCV, in which case this doesn't apply. 1 Qt/1,000 miles is the old standard, but, realistically, every 5,000+ miles is pretty much common. If you damaged the engine by over heating or running low on oil, it will probably continue to get worse. At some point, assuming a piston doesn't seize (it probably won't), the plugs will foul out and require replacement every couple hundred miles, and (assuming its leaking rings), power will be reduced until it barely runs. Smoke screens out the tailpipe might also get frequent visits by the local police, and if you have emissions, you will start to fail those inspections.

But, if it is just clearances in the motor, it may run like that forever. It might foul plugs a little more often, but that would be about it.

Grumpy Aero Guy:

GM used to say 1 qt/1,000 miles. But, you really should be checking your oil level every 2,000 miles or so, or more often if it uses oil. The Oil Life Indicator is not meant to replace the dipstick!!

Trust me, I DO.... I tend to change the oil much more frequently than the DIC would want me to and I keep an eye on it.

Still 2q/1000miles...... maaaan....

Sadly I feel like I check the oil every couple of days, especially after a long trip. I am becoming an expert! I have noticed the truck slows down quicker when I take my foot off the accelerator. Feels like it is driving through mud, or being bogged down. This is an exageration, but it is a change and this is the only way I can explain how it feels. Al the TSB's say that after it has had all the aboce mentioned repairs don't fix it, it is still under investigation. In other words-they don't know.

marnisampair · March 27, 2009

Sure you don't have any leaks? Are you getting any blue smoke out the exhaust? Pulled the plugs to inspect?

I agree that this is excesive.

No leaks! But I do smell a burning smell when you walk by the right rear tire well, probably from the exhaust pipe. Hard to tell of blue smoke as it has been a cold winter here in Minnesota. In taking measurements on the dipstick and pictures of the drop in oil, I clocked it at just over a quart in 760 miles through last oil change! My add oil light came on and my dipstick was dry at 2,600 miles after an oil change this last time. I think my service guy is begining to know me too well, spending too much time with him.