I just bought a '92 4-door
 

I am so happy, I got a GREAT deal.

The car has 135,000 miles, with one owner who was obsessed with taking care of it. It is a beautiful car and its runs perfectly!

My question:

I am looking forward to driving my Camry another 200,000 miles, and I'm thinking I should switch to full synthetic motor oil. I am thinknig that for my next oil change I should change to synthetic blend, and the change after that--full synthetic. Is there a method to change types of motor oils? And will it help my enine last longer? Additionally, will Premium gas make a difference in terms of longevity?

RE: I just bought a '92 4-door
 

Unless the engine is pinging there is no reason to use premium fuel.

The oil manufacturers state one can change back and forth between mineral and synthetic oil without problem. Some owners however who switched to synthetic on high mile engines have reported seals leaking.

Synthetic should reduce wear but would think if the engine has had good maintenance it should easily make 200K with just the use of mineral oil, changed it at regular intervals.

If the car has an automatic trans make sure it is changed often enough to keep it appearing clean and reddish on the dipstick. Otherwise it is possible the engine may outlast the trans. And the differential fluid (most likely Dexron III) should be replaced every say 60K.

Don’t forget changing the PS and brake fluid if they appear dark. Brake fluid will absorb water over time; the PS (most likely Dexron III) will oxidize and break down just like in the trans. Plus changing the engine coolant, use only distilled water.