Can I change to synthetic oil on my is 250 2009? it has 90k miles

 

YES! Just use the recommended oil viscosity from the owners manual.

 

Absolutely, shouldn't be a problem as long as you use the proper weight.

 

By the way, this is the LS forum, not the IS forum. In any event, this topic has been discussed to death, some people maintain switching to synthetic oil in an older car may cause leaks while others will argue it doesn't. Doesn't seem to be a consensus on this.

 

Swap and forget

 

food for thought, the owners manual in gcc countries such as dubai they recommend 20/50 weight oil for 1/2/3 uz and 460 motors

 

Get out of here, really? I've never heard that, you sure? Seems strange for an engine that requires 0w20 in most places. But that would be interesting for sure.

 

I just had my first oil change. I wanted 0w-20 synthetic. When my car showed up it said 5w-30 regular oil. So anyways in a month or so, I'll have my personal mechanic but in what he recommends.

 

Well, the '07s came with regular oil changes every 5k miles and I don't recall any notification from LExus that you can switch to synthetic/10k changes. Still, it will probably be OK.

 

When the average low temperature is 95f at night and 115 during the day, a multigrade wouldn't even needed! Could honestly dump a straight grade SAE 30 and be fine. The engines likely dilute 50 weights into 30's fast, especially since Lexus knows a high VI oil won't be found or utilized.

 

It just logically makes sense, they're recommending 10k drains on synthetic for the newer 460s, same engine.

HOWEVER, after a good discussion about it with my mechanic I'm changing the oil in the LS at 5k intervals with synthetic. He doesn't think 10k drains are in the best interest of the engine. Since I likely will keep this LS for longer than is typical for me I'm going to follow his recommendation.

 

Same as me. I did do a 10k OCI year before last and then did a Blackstone analysis. The report was great and I was advised to go another 2k miles. I didn't, and have returned to 5k mile changes, but it was comforting to know the oil was still going strong. That was on TGMO 0W20.

 

Roadfrog, Blackstone almost always says this as they don't have the proper equipment needed to properly test oil. Their UOA is extremely limited and doesn't really do much nor can you determine from their UOA if you can go longer on an interval.

 

I bought my 2005 LS430 Custom Lux with 72,000 and I switched to synthetic at about 80,000. It has a 172,000 miles on it now and I just took a 2300 mile trip to the mountains and got an average of 26.7 MPG while averaging 58 MPH for the duration. I use the Mobil 1 - 15,000 mile extended and just change the filter at 5K and 10K. (unless I have been driving it too hard and its real nasty at 10K).

No engine repairs (just plugs at 110K), no leaks, runs flawlessly and now complete oil change only once a year (with 2 filter changes). Overall cost is lower, less work (I do my own) and you get much better lubrication.

On the issue of 5W-20 versus 0W-20, If you read up on it, you will find that they recommend a higher rating on "W" rating in high temperature locations. The 0W is to insure quick distribution of oil on start up, which is the time when the oil is thickest and lubrication is at its minimum until the oil pressure and temperature is up to spec.

Hope this helps your decision...

 

Their tests are "good enough" and shows levels of additive remaining and wear metals. That was good enough for me..