Mason

I just got this rx300 and the previous owner used regular oil. Is there any benefit to switching to Mobil 1?

Lil4X

At this point you might cause more problems than you would prevent. Syn oils are great at flowing into tiny spaces to provide a somewhat superior level of lubrication, but at 90K, you might experience a sudden rash of leaking seals and gaskets. These soft components tend to harden over time, and a free-flowing lubricant, while a tiny bit better for your engine, might not spend a whole lot of time in it.

Stick with a good dino oil - it got you this far without troubles. If you should ever tear down the engine and replace all of the seals as a part of an overhaul, you might want to consider a synthetic lubricant. Until then, you won't be doing any harm to let sleeping dogs lie.

Just my 2¢.

TunedRX300

It depends on what you wish to achieve:
For longer oil change interval, better resistance of sludge, slightly better lubrication, mpg improvement before engine reaches operating temperature, go ahead and use synthetic (as in non-mineral based) oil.
For shorter drain interval, go with a quality dino.
For those who must have Mobil despite its higher price and recent rumored switch to mineral based oil, go ahead and buy M1.
If you wish to learn more, you can start by reading helpful link such as
http://www.calsci.com/motorcycleinfo/Oils1.html

Fern

Why not give it a try and post back what you think.

Do an engine flush first to get rid of the crud the last 90k miles have left behind first.


Ever wonder why synthetic is more expensive than dino oil

parula

Fern yes why does it cost more!

Mason

Is the better mpg with synthetic before warm up really going to give me noticeable better overall mpg? Or is this just going to make a fractional difference?

TunedRX300

Depends on your usage, as Fern indicated, why not give it a try since oil choice will be your personal decision.

rl9905

I use Mobil One with my 2000 RX300. I just did my 60k miles service 4 days ago. It cost me almost a grand for the service but then i had other problems too so it was a more than a grand. My Oxygen Sensor was bad and Something bout Mass Air flow was bad too. Total including 60k miles service and Repair of the Oxygen sensor and Mass airflow was $1600.00

Anyhow, I switched to Mobil One at 50,000 Miles and i notice a BIG POSITIVE difference. I had a little increase in MPG. The Engine Shifts a lot smoother. I feel just a bit more power and the response is better too. I usually go to Costco or Sams club and buy the oil and bring it to the Dealership and have them use my oil.

As for Why does Synthetic cost more?, cus Syn oil is made in the lab from scientist who wear a white lab coat. While regular oil is from the earth. That's what i think.

TunedRX300

FYI, you can read this thread. Almost all synthetic oil sold on the market do not qualify the definition you just posted. Mobil 1 just changed formulation, still a good oil but just not it used to be.
https://www.clublexus.com/forums/sho...d.php?t=269982

rl9905

Do anyone here know if Mobil 1 is from GROUP III or GROUP IV? I just did my 60K miles service and used this oil. It says "SuperSyn Techology" and "Fully Synthetic Motor Oil". But i remember i heard somewhere that Mobil One is Group III. I'm not sure if that is true but wanted to make sure.

TunedRX300

Again, Exxon Mobil will not answer your question because its formulation is "proprietary". Of course, you can choose to believe them, or not. Just like usage of dino and synthetic oil, after all it is a personal choice.
Read Tom NJ comment on M1 5w-30 EP, very interesting thread
http://theoildrop.server101.com/foru...0&fpart=5&vc=1
Also check out Mobil Japan website, use babelfish to translate into English, see what XOM says about 5w-30

dfish

I emailed the product support people on the mobil 1 site, and they deftly dodged answering whether they used group III or completely group IV. After 3 correspondences and still no answer, I gave up. I asked what percentage of the formulation was group IV oil, and they said it was "proprietary information."

It seems to me if they didn't use any group III, they would definitely come out and say it because thats something you wouldn't hide and its something to help you market the product.

Try emailing them and see what answer you get.

Back to the original post:
I switched to mobil 1 at 85k and my engine runs much smoother. No problems with the switch. After i discovered the changed formulation, I bought some german castrol and I'm switching over at my next oil change. Mobil lost a customer.

Fern

- Higher resistance to thermal breakdown
- more protective qualities than dino
- detergents added to clean as it protects
- lasts longer so fewer oil changes (more environmentally friendly)
- Engineered to close the gap where dino oil has shortfalls.

I personally think the day will come when synthetic oil will be cheaper than dino oil for obvious fossil fuel reasons.

At the end of the day, to each his own.

My main reason on the RX for switching to synthetic is I started noticing some cruddy stuff caked on to the baffle on the oil fill area in the valve cover and with the horror stories of sludge, decided to go synthetic where sludge is not a concern.