Plarka wrote:I'd like to use synthetic because I heard you don't have to change it as often, but can I start doing that at 203,000 and 123,000 miles? Might my cars object?
As long as you drain the old oil out, going to synthetic will do no harm. It will help keep your 123k's engine going for another 100k. Regular oil changes are more of a determining factor. You can often get Mobil 1 synth cheapest at WalMart in a 5 qt jug. Just don't use the whole jug (save 1/2 qt).
I use the Mobil 1 oil filter ~$10 bucks if I can get a coupon code, buy online, and pick-up from the auto store.