gino01

I have a 2002 RX300 at last oil change (90,000 miles) I switched to Mobile 1 Synthetic. What do you guys think is an optimal oil change interval to follow (miles and time)? Dealer says 7500-10000 miles is ok.

hypervish

Welcome to Club Lexus!

Depends on how you will be driving. If it is all city driving (fuel dilution, etc really kills the oil), then 5000 miles. If it's a mix of city and highway then 7500 miles. I honestly, would not go much more than 7500 miles.

IMO, I don't recommend going to 7500 miles. I myself stick to 4000 mile OCi's, and that's with my 2000 mile road trips.

carguy07

Strictly my opinion, but I would say 5k miles. Would not worry about time unless it's going more than a year.

If you just changed over, I would do it again at 3k just to get out the rest of the old dino and all of the crud that synthetic seems to loosen up.

dbui

IMO Mobil1 synthetic 5w30 one year or 4-5k changing interval, you can go to 75k but why take a chance. Costco sale $26 for box of 6qts Mobil1 5w30 syn, get an oil filter with some elbow grease, and your car will be happy camper.

iolmaster

iTrader: (1)

Oddly enough I just had this conversation with Flow Lexus in Greensboro. Lexus does not recommend any change in interval when going to synthetic oil. They also don't recommend going to synthetic oil at all for engines that did not come with synthetic from the start. The service adviser said there is no evidence that synthetic does anything to increase engine life or gas mileage. He did say that if you live in Alaska or drive in extremely hot conditions often it may be some benefit. Having heard that, I decided to stay with conventional oil for the duration of my ownership.

RX300CE

My 2002 RX300 did not like M1 synthentic because of rear main seal leak, so I switched back to conventional oil Castrol GTX 5W-30, I am happy with conventional oil .

lexus114

Good ole GTX . And Valvoline White Bottle or VWB, cant beat these two oil`s. PYB or Pennzoil Yellow Bottle didnt seem to run that great in mine for some reason?

gino01

Thanks for the welcome and replys everyone. Lookin forward to being an active part of forum. Everything I have seen so far has been great. The advice was very honest and helpful.

I do an almost even mix of city and highway driving (lean more towards highway). With an average of about 12,000-15,000 miles/yr. I live in Buffalo, NY so weather can be a factor.

I purchased the '02 RX300 this past February. It's in amazing mechanical and physical shape and hope to enjoy it for many years. Therefore, i want to do everything posible to maintain it. I assumed synthetic was the best choice for the engine. I just didn't want to offset syn oil benefits by waiting too long between OCI's. Even though its marketed as acceptable. I also didnt want to do harm by switching oils so late in the vehicles life. Dealer service advisor gave a convincing speech on Mobile 1 syn benefits.

My plan was to go 5-6k on Mobile 1 syn OCI's and include tire rotations for a consistent and easy to remember schedule. Some have said dosent matter what oil you use OCi's stay same 3k or 3 months. Others have said doing so wastes cash. I only care about doing what is best for engine and not doing any harm. You guys are the experts with hands on experience, so your advice is important to me.

mckellyb

I'm going to be the outlier here, and say, on M1, go 10K miles between changes.

My wife's car, while it has only 108K on it, has seen M1 since new. I have the dealer receipts to prove it, and we bought it at 32K miles.

We have no issues with ours, and while it's probably 75% 'highway' driving, I don't know I'd change it were it used on a Texas commute.

The oil life indicator on the 2005 Cadillac STS I have, with the V8, gives me right at 12K miles between changes, with a 3-5% 'cushion', before reaching 0% life. Of course, it holds 7 quarts, and I use M1 in it, too.

Vehicles which leak oil after converting from dead dino juice to synthetic are much less common, now, as seal/gasket technology is much better than it was 20 years ago. There used to be a compatibility problem, in that synthetics could 'sneak past' the gaskets. Also, theory had it, the synthetic tended to clean the engine's internals of deposits left by the prehistoric stuff, and previously plugged leaks appeared.

Regardless, I think you're just fine on a 5K-6K change interval, though it's probably a little excessive.

Before anyone says, "but, but...that's too long!" I've owned three vehicles, one Japanese, two American, and used Mobil 1 in them. All three made it to, and past, 200K miles, using 'extended' intervals, and not one of them either used excessive amounts of oil or had one oil-related engine issue.

Actually, except for a head-gasket on one (which was likely my fault from years earlier), none had any engine problems.

I fully expect to have the STS until 200K, because I'll be able to afford a 2009 Jaaaaag XJ Super V8 Portfolio by then (2017...at least), and the RX300 indefinitely, even though my wife started eyeballing replacements.

If she wants a new car, I'll keep the RX and do something with it...it's that simple. The car has a value of about $9K. Nope, not enough...worth more to me as a third car.