Rx300 Oil Change

[richie711]

I was wondering what type/brand of synthetic oil is recommended for a 99 rx300, and how much do i put in?

[lenore]

Any good synthetic oil would be fine 0-30weight Castrol is what I used. But just make sure it is synthetic as these engines are prone to sludge...With filter they hold 5 quarts...I like the new Mobil 1 0-20 also....

[RX350lover]

Switching to synthetic is an excellent idea. Just know that if your car is high mileage (more than 60,000 miles), you should do another oil change in about 3,000 miles. The dino oil has left sludge and the synthetic will wash all that away. So you want to remove that sludge from your engine asap instead of letting it float among the oil. Also, sometimes and mostly on engine with more than 100,000 miles, doing a switch from dino to synthetic runs the risk of having seals that will leak as the sludge was what prevented your seal(s) from leaking. In particular the one between the engine and the tranny.

I have switched all my cars to Mobil 1 synthetic and some cars had about 100,000 miles and I have been very lucky. Never a leak except for the gasket of oil filler cap on the engine.

Actually, when I would switch an 'old' car to synthetic from dino, I would do another oil change about 1,500 miles later. And then another oil change 3,000 miles later. In my case it was necessary in order to remove all the sludge. Also, once when I switched an old car from dino to synthetic, I initially had a lost of mpg until I had done the two additional oil changes in order to remove the sludge. I assumed the sludge floating in the oil was reducing the performance of my engine. I think I lost 2-3 mpg. But it all came back after the third oil change (about 4,500 miles after the initial switch). I have not noticed an improvement in mpg when switching from dino to syntehtic. But one thing I can assure you, the engine inside is very, very clean.

P.S. I just re-read your question and realized that I had not read your question properly. I though you were doing a switch over in oil type.