I have a 2007 Tahoe LTZ 5.3 and in between oil changes I lose between 1-2 quarts of oil. I'm not burning it and it's not leaking anywhere. I am using a high quality oil has anyone else had this problem? Does anyone know what the cause could be?

 

Well, it seems to be going somewhere

It really comes down to three choices...

1. It is leaking externally and you have not noticed it. Maybe it only happens at speed, or it collects in a frame rail and doesn't get cleaned out until you are driving. IMO, this is an unlikely situation.
2. It is leaking into your coolant. Although, I believe that you would have noticed many other problems if you had 2 quarts of oil leak into your coolant. However, you should still visually check your coolant to see if it is contaminated.
3. Your engine is leaking internally, i.e. burning oil. It may be burning so little that you don't notice it or maybe it only burns on startup from overnight valve leakdown. This is the most likely scenario. From the other posts I have seen here, there seem to be other reports of the 5.3 losing oil and no one seems to have found the cause.

 

Thank you going to chango oil today.

 

could just be useing it.. and i dont mean burning it. all vehicals use it. change your oil and check on i in about 4k miles it'll be a quart low maybe 2.

 

Maybe if it has a 100K+ miles on it or hasn't been maintained. If you're using 2 qts in 4K mi, you've got a problem. Unless you're talking about a hi-perf engine w/ loose tolerances.

 

could be like nissans 2.5l that burns it up in the cat conv. , you never see any externally. problem comes when conv plugs. oil has to somewhere ??

 

according to generel motor it is acceptable or "normal" to use /burn a quart of oil every 1200 miles before it is considered excessive

 

And they wonder why GM went bankrupt.

If a new engine still burns a qt/1200 after 1K mi., it's got a problem. May not get any worse but somewhere there's something wrong like rings that didn't seat properly or bad valve seals.

 

this is a long time since thread started, but was looking at stuff and noticed that you had same problem. i have 2007 suburban 5.3 and was losing oil like crazy. no drips on pavements. put truck up and got under and what do you know. the oil filter was just a little loose. when it was traveling down road, it leaked. tightened it right up and problem solved. the filter is in a very tight spot and hard to tighten without the loop, or bandlike tightener tool. later on i noticed the problem again. i had gripped the oil filter too tight with the filter wrench, and put a pinhole leak in it. now im very very careful. ha ha. so i can see how this would be very easy to make this mistake and think its engine trouble. good luck.

 

bigboy Welcome to the forum