We have two '99's with over 80k each. Knock on wood, no problems yet. However, we were running Mobil 1 0w-30 and were losing 1 quart per thousand on one and a little less on the other. Then we recently switched to Mobil 1 truck and suv formula 5w-30. What a difference. Much quieter and less oil use also better mileage. Just did round trip Saratoga to Montreal with the AC blowing and going 70 mph plus and logged a solid 20mpg. You can take it from there.