Quote Originally Posted by 40th GP View Post
I am not sure I agree with the 'it is all the same' logic. Synthetic is proven to hold up better under high temperatures, it has more detergents, and oil does not break down as fast (among many other scientifically proven differences). But the technical specifications are a whole different topic.
^^^ I agree...

I am not sure how you figure you save any money doing conventional changes more frequently. I guarantee this will cost you more. You are buying twice as much oil and twice as many filters (so unless you stock up all at once you can figure twice as many trips to the store), and spending twice as much time.

But all that aside, I was not wondering about oil change best practices on your own car, I am looking at purchasing one of 2 different vehicles. One has been serviced regularly at a local quick lube with Mobil 1 full synthetic at about 10k mile intervals (some closer to 6-8k, but looks like no more than 10k). The other was dealer serviced at more like 3-4k mile intervals using the bulk dealership conventional oil. Assuming all else was equal, which of these vehicles would you prefer to BUY, and why?
Oil change interval is not the only criteria I would use in considering the purchase of a vehicle... It's just not that simple! The wear n tear on the car will show me more than what someone SAYS they did in maintaining the car. Receipts or not doesn't matter cause you can change your oil regularly and beat the crap outta the car. Rust, dirt, worn suspension, brakes, tires, interior, engine sound, tranny feel, etc. will show more than a clean dipstick.

Just sayin...
: )