oil burning

[Mr 5 0]

No smoke, no leaks? Hmmmm. That oil has to be going somewhere.

It's axiomatic that a a compression check will be in your future. but there's a lot of things you can check in the meantime, including a plugged PCV screen. You'll also want to look at the spark plugs for fouling or tell-tale oil on the threads, indicating some valve stem seal leakage, which could be the problem.

Have a friend follow you onto the highway and get on it a few times, especially at 30 or 40 mph, then let off quickly and see if he notices any blue smoke on acceleration or deceleration. If he does, if it's during acceleration; it could be worn rings. On deceleration, quite possibly worn valve stem seals.

I would also keep a real close watch on the dipstick; checking it every day on a level surface with a cold engine to see if the level is dropping and how much.

Look over the engine using a droplight or strong flashlight and search for leaks, such as the rear main seal area and valve cover gaskets, both common leakage areas on the 5.0 engine.

As a band-aid, you can switch to a single weight oil (straight 30 or 40 weight) and see what that does for your oil consumption.