I recently purchased a 2000 XE with 50k miles. Not sure what the previous owner used as far as oil. My questions are:

should I try to use same oil (there is a oil change sticker in the window....I can call and maybe find out what oil was used)

Should I switch to synthetic?

Does it hurt to go from standard to synthetic?

Thanks

Scott

IMO, synthetic =

For what it's worth, I've been using synthetic since I hit 40k with no problems

You don't need to worry about what was used before.... everything is compatible with everything these days.

There are TONS of looooong synthetic VS regular oil threads on here... Use the search feature (I'd try the Backyard Mechanic section) and you'll learn more than you ever wanted to.

The short version: regular oil is fine as long as it is a quality brand - but synth is better.

You'll also find lots of info on the different oil filters. I just buy 'em from Nissan... figure I can't go wrong there.

i bought my 01 X last winter with 55,000 miles on it, i'm running synthetic in it now, no problems at all

Go synthetic.

I switch to syn too at 70,000Km for the engine, tranny and transfercase. When I did the first change from dyno to syn, I did an engine flush. Don't know that I needed to, but in my head it made sense to do it to clean the old sludge if there was any.

No need to find out what brand they used prior, just buy whatever you feel is the best your money can buy. As far as switching sythetic and dino - you can only switch from dino to sythetic safely. You can not switch from synthetic to dino. The synthetic obviously is made up of a different base which gets absorbed into the gaskets and swells them up. This is one of the reasons why some people can see a performance gain on an older engine, they get better compression due to the swollen gaskets. If the engine has previously had synthetic oil and you switch back to dino oil, the gaskets CAN and most likely will shrink and cause leaks. Now this is not a 100% guarantee, there may be some people who have switched from synthetic to dino with no problems. Depends on how tight your engine is, but there is a very good chance that you will get a leak.

The shop that I go to for my oil changes uses full synthetic Quaker State oil and a Quaker State filter. It might not be as good as Mobile1 but at $40 for a full synthetic change and a free car wash, I can't complain. And I figure the Quaker State full sythetic has got to protect better than any dino oil.

I have been running full syn in both my 2003 IS300 and 2003 Xterra S/C. All I can say is, do it man. It's gonna be more money per change but the long term effects are totally worth it.

I put in synthetic the first oil change my X ever needed. I have used it on every vehicle I have owned with great results and never a problem. Some of those vehicles I abused more than heavily. All are still on the road..

to change from regular to synth, do I just drain and fill with the synth or do I have to have it flushed first.......
and should I switch? I only have 10,200 miles on it.....

Thanks......
-Robb-

Drain and fill, they are compatible. In a couple of changes most all traces of the old oil will be gone.

And that was the old bottle style for Mobil 1. The new bottle is much prettier...