last oil change i went with rotella t 15w40 instead of the schaeffers #700 15w40 that i had been running in it for a while. and i am happy to say that my oil consumption has dropped dramatically. i was using 2-3 quarts in 3000 miles, and right now i am at 1500 miles and havent used any yet. im not trying to nock schaeffers, i believe that it is the best oil on the market. i run schaeffers 80w90 in my axles. but for the price of rotella (5.98 gal at tsc) compared to schaeffers (12.11 gal) and with the added benefit of less oil being used, i think i will stick with rotella.