Hypermilers,

I was one who always used Mobil 1 0W-20. While much better then the standard it does not hold a candle to Royal Purple. I had been contemplating over the last few oil changes and finally made the leap this last time.

I now have 30000 miles on the car I am much more in tune in sensing the feel of my car (driving with my shoe off helped a lot). I was down to 20% effieciency before the RP oil change and could feel the viscosity resistance in the engine. Not to mention that I rarely got above 6 bars of SOC (with a 30 mile smooth highway commute) and it was getting harder and harder to stay under 2500 RPMs.

So I purchase the Royal Purple and took a gamble with the 0W-10. I flushed the engine and then installed an K&N oil filter, 3 quarts of Royal Purple and the rest with Mobile 1 0W-20...

...It is like night and day. The car floats on air, I can glide with little effort and I get 7 bars of SOC consistently and max out at 8 quite often.

Also I never really measure but I did know that my oil life remained at 100% for a long long time. The next go round I think I will not mix and go 100% with RP.

I have spoken to a number of mechanics (one being a sprint car racer) and they all said that the only true fully synthetics are Royal Purple and Amsoil. That what you buy in the store that says fully synthetic is not.

With that being said, I have about 2 cases of Mobil 1 that I stocked up on that I would be willing to sell to someone at cost. If not I think I might use in my wife's car.

Anthony

Never knew RP made a 0W-10 and where did you get it from?

I've been checking out Royal Purple's website and do not find 0W-20 listed in their product line or their online order site.

I found it. It's listed under their "racing" oils. Here's a link:

http://www.royalpurple.com/xpr-racing-oil-pp.html

Also, checked on one site and it was listed for $12.99/qt.

So this begs the question if there is really any advantage to using Royal Purple over Mobil 1.

If we use $14.06 ($12.99/qt + tax) and $6.46 ($5.97/qt + tax) as the total cost per qt of Royal Purple and Mobil 1, then the differential is $7.60/qt or $30.40 for a fill.

Now here is where the assumptions come in.

I have not seen any gas mileage increase claims for using Royal Purple, but let's assume that there is a 1% increase. Using a median HCHII MPG of 40 that is 4 mpg or 44 miles/tank (11 gallon tank fill). The value of the tank is then 440 miles and 484 miles respectively

With gasoline at $3.50/Gallon, this means that the baseline cost of a tank fill is $38.50 with a fuel cost/mile of .0875 for a Mobil 1 car and .0795 for a Royal Purple car.

If we disregard the Maintenance Minder oil change variable recommendations and use a flat change interval of 10K miles, then the fuel cost to drive 10K miles with a Mobil 1 car is $875 and a Royal Purple car is $795, a delta of $80 and a net savings of about $50 per 10000 miles.

So if there is a gas mileage benefit of at least one-half percent then using Royal Purple may be advantageous.

What is needed now to further evaluate this are real-world MPG numbers from a Royal Purple car vs the same car with Mobil 1.

Looked at their website, did not see 0-20 oil & I am not willing to risk my warranty using the wrong grade oil. They have a savings calc. I used it and found it would save me less than 30 a year in gas.

I e mailed the, they told me to use the 5-20....lets see, thicker oil, lower gas mileage, twice the cost....woo boy, I be saving money now.

Time to get out there and race that Hybrid! I knew there had to be another reason I bought the car.

I used Royal Purple in all 3 miatas...it's good stuff in that application. I can't think of a reason to use it in a hybrid, as Honda has spent so much time and energy and R&D optimizing their car.

Actually, this would be a 10% increase. One percent would +0.4mpg or 4.4 miles/tank. The RP cost/mile would be .08663 or $866 for 10k.

To break even on the cost (using your numbers), you'd need to get 456 miles per 11 gal tank, or about a 3.6% improvement.

cheers