Yet another oil thread

[Rich Stern]

First, let me say, when it comes to oils, I have never bought into the hype of the high priced stuff. I grew up watching those 1970's Mobil 1 commercials where they suggested you could go 25,000 miles between oil changes. Uh, no thanks. Synthetic is too expensive to change every few thousand miles, and I am not going to drive around with a year of two worth of particulates in my motor oil, when it costs less than $20 and 20 minutes to replace with fresh (non-synethetic) motor oil.



Every 3000 to 5000 miles, I change the oil in my vehicles. More towing or stop/go, closer to 3000. More highway miles, closer to 5000 miles. I don't really have an oil brand preference. I'll use Walmart's brand, Advance Auto, or any of the major brands if they are on sale.



Saw something just now that has me thinking about the benefit of synthetics. Specifically about Royal Purple. There are folks that swear by it. That's fine. Not my job to convince others to believe or disbelieve their own experiences. But this BoatTest.com before/after comparison video has some surprising results. They use high-end metering equipment to measure fuel consumption on boats. The test was a comparison of performance and fuel consumption in a 29' cruiser with twin Volvo (GM block) 5.0L V8s, both with regular oil, and then again after an oil change to Royal Purple. I was SHOCKED at the difference in performance. With Royal Purpole, the boat had a higher top speed, used about 10% less fuel, and they got a 3db sound reduction from the engines.



Againk, I am shocked at this. If it had been a few percent different, I would have attributed it to difference in wind, current, temperature, etc. But the difference is too dramatic. Either they phoneyed the test results, or the stuff really is superior.



Thoughts?

 

[Dreman]

I'll take your word for it. I don't like websites that make you log in or register before you can look at anything on the site.

 

[Rich Stern]

I watched the video again, and now I am thinking this is the result of poor testing methodology. The top speed was substantially higher (in boating context), yet the top engine RPM was the same. Which means the props were turning the same speed.



They had to have had a wind, current, or (lighter) weight advantage in the Royal Purple portion of the test, which would also translate into fuel savings.

 

[Jerry Abson 3]

Wow! I am impressed with those numbers. You can't count wind, weather, or other factors that much into this test, as they were done relatively close to each other, using same waters. I am like you, I never thought the high cost of using synthetic was worth it, but if you look at that GPH, and you have a 30 gallon tank, thats almost 40 minutes of longer run time when cruising. HOLY CRAP!



I may just have to seriously think about this royal purple stuff!

 

[Rich Stern]

dreman, sorry about that. Forgot that I was registered on that site. Don't know how to post their video content elsewhere. It's propietary. Here's a test summary:



29' cabin cruiser with twin Volvo 5.0L V8s, with approximately 110 hours of run time (well broken in).



First test was with the standard oil and filter in the motors.



top speed 39.7mph at 4700rpm

fuel burn at top speed 19.5 gph

best cruise 27.2 at 4500 rpm

fuel burn at best cruise 9.7 gph



Oil and filters chandged to Royal Purple and retested:



top speed 41.5mph at 4700rpm

fuel burn at top speed 19.0 gph

best cruise 27.2 at 3500 rpm

fuel burn at best cruise 8.8 gph (this is the surprising number)



I believe the fuel burn numbers are for a single engine.

 

[user 64847]

I use synthetics in my motorcycles. They're both air cooled and the temp difference is about 20 degrees. MPG is up over the regular oil also. The truck I use regular oil in.

 

[Rich Stern]

Jerry, that was my first reaction. But how do you explain the difference in top speed at same engine RPM? Same propellors, same gear ratios. It's got to be wind or current.

 

[A1cntrler]

We sell the RP at Advance Auto, and the guys that buy it do really swear by it. You can try to convince them to try something else, but you get shut down before you even get a sentence out. I saw a guy dumping oil into our oil tank and noticed it was purple, and asked him how come he was dumping out the new oil. He said that the oil he was dumping had about 9k miles on it, and every weekend was a day at the track in his S2000, which he has put RP in it since the day it left the showroom floor. The oil was remarkably clean looking. I have never used RP before, but was considering putting it into my TBird SC once my motor is broken in. I won't drive that but on weekends and maybe a cruise night here and there, so not many miles will go on it.



Also we just started carrying RP gear oil (75w90 I think) at my store. It was 8 or 9 bucks a quart I think. About the same as a quart of RP oil.

 

[Rich Stern]

I just noticed that Royal Purple advertisements have top billing in that web site's sponsor list. So much for editorial integrity.



Royal Purple may in fact be better, but I now question the integrity of the test.



Sorry I even stirred this pot.

 

[A1cntrler]

Rich posted the numbers there while I was posting my reply.. My question about the numbers are:



How can 4700rpm result in two different speeds if there were no other factors to consider? 4700rpm would result in the same number of prop revolutions regardless of what oil is run as far as I can tell, unless it is run through some sort of transmission. A better comparison may have been to run RP in one of the motors, and regular in the other and compare the two side by side at the same time to check fuel consumption. If that was done though in tha manner, from the results they posted, it would not go straight, running both at 4700rpm, it would run in circles..lol

 

[Doug Watts]

I used to use RP. Now I use AMSoil. I can get it cheaper and the lab tests I read say it holds up better in the tests. The downside is that I have to order it from AMS, but that's not really a big deal since I ordered the RP online too.

 

[Alan Peters]

When I was contractor at GM, that's all they used was Royal Purple in the prototypes and testing. We would get 10 gallon drums of it. Gear lubes, grease, etc. Everything was Royal Purple.



Royal Purple didn't show significant improvement over other conventional/synthetic oils. The cost wasn't justifiable (and this was when GM was flushing money away). I remember a Z06 that used it and actually showed a loss in performance on the dyno verse other synthetics. Significant testing was done on daily drivers and numbers were comparable as well.



Needless to say, I use Motorcraft synthetic oil. It always comes down to driving habits and miles. I've seen putty oil in 3000 miles on synthetic and clean oil in 7000 synthetic.



RP gear oil is way to thin IMO.

 

[swshawaii]

Agree with the ORIGINAL post re: "dino" vs."synth" oil.

Have two personal friends who distribute "Amsoil" and "Synergyn" products exclusively in the state of Hawaii. (Chuck Garner "Amsoil" and Wink Arnott "Synergyn")

Have questioned BOTH regarding scientific testing using API measuring standards with few or no substantiated performance, mileage, or wear claims.

IOW- INCONCLUSIVE. Opinions greatly appreciated.

 

[Todd Z]

At school we did a Senior seminar project on an engine DYNO ( MY mustang motor, and another newer 302) spark plugs, Carburetors and Oils...



We found that certain plugs used more fuel then the OEM style, some holly carbs worked just as good as edelborck and the toilet bowl Predator carb.



With the oils we did find the synthetic made only a few 2-3 HP more then conventional.



BUT the motor did wear significantly less running synthetic oil vs the conventional with all the dyno pulls..



ON MY ST:

I switched the FT and Rear and motor to Royal Purple and made 0.0 HP on the dyno..



Todd Z

 

[Rodger Tellefson]

I read an independant truck magazine article on RP with noticable improvement when they put it in the engine, transmission and differential. When I switched to RP back in '04 I put it in the engine and transmission, and noticed the engine was quieter with smoother acceleration. And, in '06 when I switched to the TrickFlow diff. cover I put in RP and documented an increase of 1-2 mpg.

 

[Alan Peters]

I've seen extreme high horsepower funny cars, pushing 1200hp gain 50hp on its power band using RP, but again, its all about the application.

 

[Richard L]

I used to think like Rich Stern regarding synthetic oils. Early on, they offered extended oil change intervals, but most factory warranties would not honor the warranty if you did not change oil as often as they recommended even if you used synthetics.



Since then, many vehicle manufacturers have actually started putting synthetic oil at the factory and including the extended oil change intervals in their warranty and maintenance schedule. Also, Oil filter technology has improved greatly over the years and the better filters can filter the oil for a year or 15K miles with no problem



My 2008 Mercedes comes from the factory with Mobil-1 5W-40 and they only require oil changes at 1 year or 13K mile intervals. In fact I just had my oil changed yesterday as well as they usual check...$230. Of course the dealer charges $8.43 per quart for the oil and $15 for the MB oil filter, and the V6 engine requires an amazing 9 quarts of oil !!



...Rich

 

[Bill Barber]

Anyone noticed the major price jump in RP oil, two yrs ago it was 6 bux a Qt, now it's near 9.

Switched over to Mobil one.

 

[Rich Stern]

Anyone noticed the major price jump in RP oil, two yrs ago it was 6 bux a Qt, now it's near 9.

Switched over to Mobil one.

Probably a little bit based on raw materials, but also marketing strategy. Now that there are quite a few competing synthetic brands, including some store branded stuff, the Royal Purple marketing folks are probably trying to move into a pricing area of the market where they won't be perceived as a commodity, and won't compete, price wise, with similar products.



When Walmart starts selling synthetic motor oil at $16/gallon, and you have a competing brand, you really don't want to hang around in the same marketing space. It's not good for your product's health.

 

[Jerry Abson 3]

If two engines are producing the same rpm's, but one has more HP, wouldn't that be caused by the transmission recieving more torque? Thus applying more total HP and thus speed to the tires? Or in this case, the prop?



I see there is still alot of 'if' in this thread. So that tells me there is no un-biased, purely scientific testing for this product. Hasn't anyone done any ASTM tests on these claims?