Something is likely amiss. My 855D and 865R (same engine) have pretty much been tight on oil, with maybe a 1/2 quart max in 100 hours. That was until I put a turbo on the 855D. A little bypass through the shaft ring adds up so I have to add 1/2 quart every 50 hours. If you don't have a sweat leak, then take a look in the mirror stepping on it from a stop. Look for Oil smoke which is bluer than diesel smoke. JD has the fuel choked down so you shouldn't have diesel smoke. One reason you can get oil blow by is the original owner decided to ignore the break in procedure. One thing you can do is check with JD and see if replacing the oil with the break in oil at this stage will do anything for you.