Originally Posted by greatdreamer369
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.