My bad; I just saw 500 or 1000 miles in my head. I read to many "oil missing" posts.

Try a compression check on the cylinders; a screw in gague will tell you if you're blowing past the rings (sign of burning oil).

Emissions check should also tell you.

Look at the under-body--is it wet with oil? It might have a bad seal that leaks at higher pressure (highway speed) and not at all during lower pressure (the last 1/2 mile to the house down side streets / in the driveway).

More info we get, better answer we can give. And sometimes we're accurate, too!