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The power of beer
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Discussion Starter #1
Ok, I have a '99 Silverado with the 5.3. The truck has about 83,000 miles on it and is burning about a quart of oil every 800-900 miles. There are no leaks anywhere that I can find, it is just using it. I have changed the PCV valve and am currently running 10w-30 Havoline motor oil. I am also using 2-3 quarts of the Lucas oil stabilizer, but it hasn't helped. If anybody has any suggestions on what I might try to slow this down or what might be the problem, please let me know. Thanks.

Jeremy
 

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Wow thats alot of oil. Might check your tranny fluid, I've heard of cars leaking oil into the tranny... Also, what does the oil look like? is it foamy or anything?


EDIT: Also, how is your antifreeze/coolant? I'm thinking you might have a blown head gasket, or cracked head/block.
 

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samcarol
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better than my friends old geo... don't ask me why he's had two

He'd go through about 1 quart each tank. And a geo only takes a quart of oil... :driver:
 

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I had a buddy that had a '99 Silverado and it burned oil often and he took it in and they had a hole in a piston. Hopefully you don't have that problem.
 

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The power of beer
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Discussion Starter #6
Coolant looks fine and level is always correct. Oil isn't foamy or anything. As far as blue smoke, I am not sure. There is a black spot on my garage floor where the tailpipe is turned down, though. I actually checked my tranny fluid the other day, and it looked good so that isn't where it is at. Should I go to a heavier weighted oil like 10w40? What about any other type of additives to help? Thanks for the input.
 

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Put your finger inside your tailpipe tip, if youv'e got oil coming out there, you'll know.

You might try switching to a heavier oil, but that much oil with that few miles isn't a good sign.
 

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The power of beer
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Discussion Starter #8
Yeah, I thought it is kinda bad myself. There isn't any oil in the tailpipe, but it is really black and sooty(sp). Thanks again. By the way, what does it mean if there is blue smoke?
 

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Bluish white smoke is burning oil - usually can smell it too. That black and sooty stuff, I dunno, I can't remember what it means lol.
 

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black is usually rich running. Not always.

There are a few things, rings, valves, valve seals. With that much oil being eaten you should see the blue smoke out the tailpipe. The easiest things to do would be a compression check and a leakdown test. That should give you an idea of what is causing the problems.

heavier oil might slow down the consumption. My buddy ran 20-50w in his bronco because of oil consumption.
 

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5.5MPG!!!!!!!All Day Long
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try running mobil one synthetic. 20w50. we recommend it to all our customers with oil consumption probs. it usually works. but expensive. also is there any noise from the engine ever and does the truck still run smooth. another thing is it could be bypassing the valve stem seals. pull a plug and look at the porcelain tip. if it is brownish or black on one side and lighter on the other side, then change ur valve stem seals.
 

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The power of beer
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Discussion Starter #12
Great info there guys. I will pull one of the plugs and check the color. I think I will try the heavier weight oil also because it sure couldn't hurt. I used Mobil 1 before but it was 10w30 and it got really expensive adding oil all the time.
 

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Sounds like the perfect time to drop a 6.0 in there. :ninja:
 

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The power of beer
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Discussion Starter #15
The only knocking I hear is what has always been there on startup. Now, that I think about it though, it has been idling a bit rougher when I stop at lights and such. The 6.0 is a good idea, but I think I need to be selling it instead. I just don't think I can put any more money into it. :bawl:
 
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