Disappearing Oil

OK Gang....heres one for ya!
I have a 2002 GMC Yukon XL w/ a 5.3L V-8. It has about 36K miles on it. In the last 4 months I have had the oil changed twice and right
before it comes time to change the oil the "Check engine oil level" light comes on. I pop the hood and check it and I am between 1 and 1-1/2 quarts low. No leaks, and the oil isnt dark (like it would be if it were burning it). No smoke puffs from tailpipe when I start it either.
so if its not leaking and its not burning, where is it going?
I made extra sure the last time that they were putting in the proper amount also.
Thanks
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You didn't mention how many miles between changes. As an aside I wouldn't wait until the check engine light comes on to check and add oil.
It can be burning oil with out having the puff of smoke or a smokey exhaust. If it is burning it at a very slow rate, then it will not show up in the exhaust as a big white puff.
Other place you could look is the coolant. If you have a blown head gasket, then it could be pumped into the coolant water. Hope not.
Take a look at the end of your exhaust pipe when it is first started in the morning. With someone else starting it. See if there is any blow by then.
good luck.
Mark

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I've been running between 5k - 6k between oil changes. The thing is this just started about 2 oil changes ago (around 25k) so I worry about it.
How would one check the coolant? or is this something the mechanic should do?
thanks

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With the engine cold you can look open the radiator cap and take a look at the color of the coolant. It should be green or orange depending on the brand. If oil has been leaking into the coolant it will have a milky look.
Did you use a new brand of oil. Or did the mechanic not put the plug in tight or strip it. Could it be leaking from the bottom of the oil pan plug?
a good mistery.

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<snip>

Your engine, mileage when the problem began and symptoms of excessive oil consumption indicate you may have the dreaded "piston slap" ... but you make no mention of audible slapping/knocking sounds from the engine.
See:
http://www.google.com/search?hl=en&ie=UTF-8&oe=UTF-8&q=gm+piston+slap
for more info and listen for the telltale sounds on cold start-up.
VLJ
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Check the tail pipe. It should be a light tan color on the inside. If its black and your finger gets dirty when wiped inside the pipe, its burning the oil. Regards, Dale

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On 7 Jul 2003 09:01:21 -0700, snipped-for-privacy@bww.com (FlagshipOne) wrote:

I actually have the same issue on a 2001 Suburban w/ 5.3L. It uses roughly a quart or so every 3-4k. However, my 2000 Silverado with the 4.8L uses no oil at all between changes, and it has 60k on it right now. I sure wish I could figure out why the Suburban is using oil though, and GM is of course no help at all (it is normal they say. Uh-huh, sure...)
-Jeff
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All this info is good stuff....while bad for the vehicle, still good stuff.
Now that you mention it, the thing has always had a little 'slap' when you start it. Doesnt do it all the time but does do it. I just thought it was the oil draining down into the pan or something.
so what are my options: can it be fixed without mortgaging the house or should I start looking for another horse?
snipped-for-privacy@bww.com (FlagshipOne) wrote in message

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