I had my VC gaskets changed 5 years ago. I still have an oil leak and it's much more when the 99 is on a steep driveway incline, engine up. I was gone a week and noticed that I lost 3/4 Q. I knew it leaked more than on level ground, but not that much. Any ideas where the leak is? I thought of trying the Autozone stop leak stuff, I see there is no talk of that. Maybe for good reason. I'm getting oil burning smell more often. I see that there are many happy owners with leaks and are content. I'll try tightening the oil pan screws and degreasing but it's a pain getting under to the skid plate area without being a grease monkey with scrapes.

When the vehicle is sitting flat a lot of leaks will accumulate in the skid plate.
When you park on an incline, the accumulated fluids tend to flow out of the plate.
How many miles does it take to go through 3/4 of a quart of oil?
I doubt if that much can leak just sitting there. If so you'd have major issues while driving.

3/4 of a quart would be a HUGE mess on the ground. Like, trail to the back of the truck mess. Sounds like that happened over a much longer period or you are also burning oil.

Snug down the valve cover gasket fasteners (do NOT "tighten" them - the torque spec is quite low). Clean everything up (simple green or other engine cleaner, hose sprayer) and see where it is leaking. You might need a mirror to see the back of the engine to spot a leak back there.

-Charlie

If you have no obvious current leak spots (old spots grime up and stay around for years until cleaned) then you'll want to look further down the engine. Could be leaking from the oil plug with a loose bolt or no washer, from the oil pan and drips down the pan or from the rear main seal. For most people, just spending a little bit of time wiping things down so all the old grime is gone will make it much simpler to find the current leak as the new oil will look beer colored and not black. If time or space is an issue try buying some UV dye. You put in the UV dye, drive around for a hundred miles or so and then check your engine bay with a black light. Any new leaks will glow and identify the source. If it's dripping, look above the drips to find the source.

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