The G Man

Most synthetic oil will last 15000 miles, its the filters that wont last that long. Most european cars have been using oil filter that are 2 or 3 times the size of Japanese oil filter in order to prolong the oil change interval. Even with the bigger filter, they are still only recommanding 10K change interval.

xfirechief

Without using a brand name some filters sold by the synthetic oil companys website last for 1 year or 25K miles. BUT, as of now they do not have a filter for the LEXUS we have so I change the filter around 5K & top off the oil level & change it all(oil & filter) once per year which is around 15K for me. So I use 3 filters per year, one oil change which is a total cost of around $45 per year.

The G Man

Do you mean amsoil filter? For me, if I am going to change the oil filter, I might as well change the oil too.

xfirechief

If u think that way then synthetic may not be for u. If u change oil & filter every 5K at a dealer maybe we are talking $150 per year for dino oil versus $45 with DIY using synthetic. If u do the dino oil changes youself it could still run u more then $50 per year.

Nothing wrong with doing it the dino oil way but getting all the synthetic benifits for about 2/3's less $$ then the dino way sounds better to me.

The G Man

I hope you are not doing 15000 miles oil change on your brand new Lexus, I believe that is grounds for Lexus voiding your warranty if you have a oil related issue.

xfirechief

Have never had a oil related issue since 1979 but if I did the synthetic oil company has a warranty that if it was proven that it was an oil related issue they cover it 100%.
The lube never wears out, it is the contaminents that causes all the problems, that is why filteration is so important.
Many studies have been made for synthetic versious dino & the short story is dino lube produces sludge & varnish while a high grade synthetic does not as it runs so much cooler.

Teletubbie

With all this discussion about synthetic vs conventional oil, I am confused. I just got a new 2009 RX few weeks ago and what oil should I use? I drive around 10K per year.

xfirechief

Use only a good synthetic oil weather u change it every 5K or 10K.

skoh

My personal recommendation is to check your owner's manual for the viscosity grade of oil. For the 2010 RX-350, it is 0W-20 synthetic oil.

I'm sure 0W-20 is available at the dealership. However, if you are inclined to do it yourself, then, I would make sure to use an API approved oil:
http://eolcs.api.org/FindBrandByVisc...iscosity=0W-20

I use 0W-20 and change every 10,000 miles at the dealership for about $71.
It's just convenient for me as I'm not mechanically inclined and don't want the hassle of buying the filter, collecting & disposing used oil, etc.

DNC

You are kidding, right? Oil is for both cooling and lubrication. Without a doubt heat breaks down oil and it's lubrication ability.
There is no car manufacturer or motor oil company that would suggest changing filter without changing oil. If cost is an issue I would use conventional motor oil. As much as these cars cost I'm not going to cheat on service or I would buy a cheaper car.
This thread repersents the reason I will not buy a car without a full service history.

xfirechief

SORRY BUT THERE IS:
One of the major synthetic oil companys does just that. Then within the last year they came out with a new type filter that goes 1 year of 25K. Blows your mind, right? 100's of thousands of miles without an oil related problem too.

Your not cheating on service, you would be using the best products available for your "expensive vehicle"

The G Man

I think anybody can find documentation from the oil manufacturers that claims their oil can last XXXXX amount of miles. I like to see a indepenent studies' results, an oil analysis report. Oil will break down sooner or later rather if its dino or sythetic. If you use sythetic and change your oil longer than Toyota's recommandation and have a oil related problem, which is very very unlikely by the way, good luck if you try to get a new power train form the oil manufacturer. The oil company will come up with more excuse than your dealer will

xfirechief

With 4600 posts u must have heard it all & wrote about it all but I suggest u check out some independant studies, it may just change your way of thinking about synthetics.
Syntheticas last way longer then dino oil, it is the contaminents that causes all the problems which means u need the proper filteration.
Again, cooler lube temp means less friction which means less wear which means longer engine life which means, will I can go on & on but why I couldn't change your mind in a 100 years.

The G Man

You dont need to change my mind, I work as an engineer for a production plant. We changed over to Royal Purple synflim GT synthetic gear oil years ago and we have monitoring equipments that can prove mechines run cooler with less vibration using synthetic.
The point is, even if I use synthetic in my car, I would not go 15000 miles. Thats 3 times the factory recommandation, but its your car and you are willing to assume the risk, then more power to you. I would rather spend a $100 more a year and go by the factory recommandation just to be on the save side.

DNC

Any company making the claims you describe is simply nuts. There are too many factors that figure into the equation for a company to say such extreme neglect can be survived by a car's engine, besides not all engines are created equal. I suspect I know the company you are talking about and I don't consider them a major motor oil company. These kinds of claims seem to surface about every ten years. What blows my mind is people believe it; Slick 50 comes to mind from back in the 1980's. Now having said that, you will spend much less on service than I will and trade your car before any problems surface. I will own my car 200,000 to 300,000 miles and cannot take the chances you describe. Your service cost will likely be cheaper and you have won the game on service cost hands down. One can argue your practice from the standpoint of cost but I am not drinking the Cool-Aid on the service practice you describe being correct, nor would I want a car with that kind of history. The second owner will pay the price.
Bottom line is we are both doing what works for our length of ownership and what we expect from our cars.