[QUOTE=christcorp;6061043]I'm not sure if using Royal Purple is beneficial or not, but I have noticed some differences. I have a 1994 Ford F250 with a 7.5l 460ci V8. If you are familiar with the temp gauge, it has 2 lines on each end with the word NORMAL in between them. Using dino oil, Mobile 1, and Wal-Mart Super-Tech motor oil, the temperature gauge always showed around the "O" in the word normal. Using Royal Purple, it usually runs half way between the first line and the letter "N". Obviously much cooler. I went back and forth twice and confirmed the drop in temperature. Now, whether or not running cooler is good or not, I'm not sure. Some may say that if the engine runs too cool, the computer will try and run it richer; thus worse gas mileage and more carbon. Others say the opposite.

I'm not sure what if any, changes in fuel efficiency Royal Purple has. I experiment so much with things such as Acetone, Lucas, Seafoam, and others that I don't have a consistent enough baseline to determine if Royal Purple helps gas mileage or not. But I do know with Royal Purple, the engine runs cooler and smoother. There's almost no hesitation or stutter. Especially when idling. It's never bad, but you can tell a difference with Royal Purple. It's not a placebo affect, just hard to explain.

Now, is it worth using Royal Purple or not, that is the question. Because of the climate where I live, and the extreme altitude I drive at, I change the oil in my truck every spring no matter the mileage. (Mileage is around 6000 miles. I know synthetic can go more than that, but again with the extreme temperatures and high altitude, I change it once a year no matter what. Royal Purple is found at our local Checker Auto. Normally it's $6.99 a qt, but almost anytime I check it out, there is a sale down to $5.97 a qt. So, for the 5 qts I need, that's $30. If I buy the 5 qt bottle of Mobile 1 at Wal-mart, it's $24. So, $6 more isn't bad. If I buy the Super-Tech synthetic at Wal-Mart, it's only $14. The $16 is a big difference. Some people say that as long as the motor oil meets all the specs, then you are better off buying the cheaper oils. Some actually believe that Royal Purple, Mobile 1, etc... make a difference.The way I figure it; No one has ever really said that Royal Purple has DAMAGED their vehicle. So, for the extra $6-$16 for an oil change; once a year; thus equating to $0.50 to $1.35 a month. For that little extra, it was/is worth a try. So far, I haven't had any problems with it. Again, it runs significantly cooler engine; (Not sure if that's good or bad) and it sound smoother.
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Sometimes people think a synthetic oil, or in this case Royal Purple, will make night and day difference results, as compared to a regular dino oil. Or that a 300 inline six engine will suddenly have additional gobs of power. it won't, but I see it all the time in expectations in people.

Royal Purple will however, pump to the top of your motor as effienctly as any synthetic oil will. If you have an engine that will deliver 17 MPG TOPS, than you'll achieve it with Royal Purple oils, nothing more, nothing less. If a certain engine only gets, say 17MPG, tuned to specs, RP will not deliver 23 MPG, or a huge difference, like that.

The thing you must realize is, with ANY engine, Royal Purple and other good synthetics will help that engine run efficient, as make as much peak horsepower as possible within that engine. Those benefits save $$ at the pump and over the life of the engine, bottom line.

 

[quote=Ed;6069147]I agree with that, I don't think it is a miracle oil, just want to make sure it is a good oil.

 

Seeing as how synthetic, because of it's molecular structure, is said to flow easier & faster, than a dino lube, has anyone, using the engines specified viscosity lube & with a "REAL" oil pressure gauge, ever noticed any difference in oil pessure readings, cold, or hot, between dino & synthetic crank case lube????

I know oil pressure is a measure of the "resistance" of oil to flow in a system, so seems to me, IF there is a measureable difference in flow resistance, we should be able to see it in the oil pressure reading, as a slightly lower value.

A lower number shouldn't be a concern, as long as the volume the pump is supplying to the engine isn't affected.

I've used the specified viscosity Havoline 5W-30 synthetic in my 99 4.0L Ranger, but it has a "idiot" oil pressure gauge, so I don't know if there is a difference in cold & hot oil pressure readings between synthetic & dino.

Now in two identical road trips, to the same destination, over a period of years, using the same gas & oil brand, tires, load & filling up before & after, at the same station, pump, facing the same way & filling at the same pump speed, I have been able to measure an increase in my highway consumption by 1.8-2.2 mpg, BUT to date haven't been able to measure ANY improvement in CITY mpg, while using the Havoline synthetic & Texaco or Chevron gas!!!!!

So, for me, from a mpg standpoint, synthetic might make sense if I were running the interstate every day, but from a mpg perspective doen't make sense for my type of city driving, in my area, in my type of engine.

SO, has anyone noticed a difference in cold & hot oil pressure readings & any difference in city or highway mpg, between the same weights of dino & synthetic crankcase lubes????

 

Remember, oil pumps in general pump a little more than needed, and there's a pressure relief valve!!

I don't doubt your numbers, but I don't believe that they're due to a different oil.

 

Well the trip was made about 5 times total, 3 with 5w-30 dino Havoline & twice using synthetic 5w-30 Havoline & at all times using a Motorcraft FL-1A filter.

One of the trips was made with dino in between the synthetic uses. None of the dino using trips yielded mpg better than 23.

Both of the trips using the synthetic Havoline yielded 24.8 mpg, the best highway mpg this engine has yielded to date. The last trip with synthetic was Sept 07.

All of the trips were taken using the exact same route & running the posted speed limit, which was between 45-70. The round trip was 386 miles.

The only difference was the oil, synthetic 5w-30 Havoline on two runs & dino 5w-30 Havoline on three runs. All fuel fillups & refills were made at the same station, same pump, facing the same way & fillng at the same speed!!!!!

So having made the same trip so many times & yielding 24.8 mpg both times using a synthetic, but never topping 23 with the dino Havoline, has convinced me that for some reason synthetic yields better highway mpg in my pushrod 4.0L.

I've never been able to measure an increase in city mpg, using Havoline synthetic crank case lube though.

So for me, if I were running the interstate every day, I'd sure opt for Havoline synthetic 5w-30 in my ride.

Will other synthetic lubes yield the same results, I really don't know, as I've not tried other brands. But it's sure easy for someone to run their own tests, just keep a mpg log on every fill up as I've done for the past 8 years!!!!

Just a bunch of thoughts for pondering.

 

How correct you are. When I bought my Ninja 2 years ago I was going to run a good grade of motor oil in it & when I said something about it to the mechanic he told me that years past you could but with all the reformulation of auto oil to meet smog requirements etc., that I would be asking for trouble down the road. He strongly suggested I use motorcycle oil which I do. Again I'll listen to mechanics that are much more up to date on changes than my old school self. I'm slowly having to admit that many old school stuff DOESN'T WORK TODAY. because of change.

 

If you put "energy conserving" motor oil in a motorcycle with a wet clutch, you are going to have problems. The friction modifiers for CAFE (not exhaust emissions) will cause your clutch to slip. Special motorcycle oil is a little overpriced. Shell Rotella T synthetic is a better choice for the money. It has no friction modifiers and enough ZDDP to protect the gears.

Jim

 

For the argument's sake I could believe a few percentage points, but nearly 10% -- that's just too hard to believe.

You would need to rule out all miscellaneous variables like tail/headwind, temperature, humidity, gasoline (seasonal variations!), etc., to be able to ascertain that your mpg increase was indeed due to the different oil.

Since you didn't see any change to city mpg, that's to me is actually a strong hint of a confound. Also, it wasn't a blind or double blind test, but if you just ran on cruise control, that shouldn't really matter.

 

Yup most of the trips mileage was done with the cruise control set to the posted speed limit. I'd usually cut it off when we hit the hills during the last 50 miles, or when in traffic.

All trips were in the March/April/Sept time frame & departure & return times were early morning, late evening, so weather variables were minimal. No stormy or extra windy days & no stopped traffic, as we time our departures to avoid rush hour traffic.

I tried to minimize the variables as much as possible.

I don't know if part of it is lower pumping losses, or what.
Anyway thats why I was asking if anyone with a real oil pressure gauge has noticed any difference in oil pressure, between synthetic & dino lube, of the same viscosity range.

I know it's not scientific, but I can tell/feel/hear a difference in how it's running at 45 mph & up, so I usually have a pretty good idea at the beginning of the trip, when it's going to offer up better highway mpg.

Last Sept it had been a couple of years since taking the trip, so I wondered if the last of the Big Lots Havoline Synthetic was going to offer up better mpg & it did, exactly the same 24.8 mpg, as it had on the last trip to the same destination.

Don't understand why I'm not able to measure any difference in city mpg between synthetic & dino, but to date I haven't been able to.

So seeing as how most of my driving is urban & rarely highway, I don't see that Synthetic offers any measureable advantages for me, so I just use dino Havoline!!!

Would other synthetic brands offer up improved highway mpg, I don't know, but synthetic sure seems to have improved my highway mpg, so I would encourage others to try a synthetic of their choice, if they're driving mostly highway & see if it'll do the same for you.

 

I started using RP in my 79 after my brand new engine lifters started going out, it didnt stop them but the engine runs much smoother and cooler. So now I use it in all my trucks.
79 Ranger 03 Ranger and 94 Bronco RP for life.

 

[quote=Ed;6069147]Interesting observation about the engines temp Ed, but I don't know why it would register a different engine temp between different crankcase lubes, as the engines temp is controlled by the coolants thermostat. The engines thermostat opens & closes according to coolant temp, not oil temp.

I've never noticed a difference in my 99 4.0L Ranger, or 94 3.8L Taurus engines operating temp, when using synthetic, or dino crankcase lube, nor would I expct to.

How ever I have been able to detect a very slight difference in the Rangers Tach rpm, ( slightly lower with synthetic) at the same highway cruise speed, between dino & synthetic Havoline though!!!!!

Again I wonder if it's lower pumping losses with the synthetic, that are part of the equation, but it's real, you can see the difference on the tach?????

Just some more thoughts for pondering.

 

Link to independent tests

Why Use Royal Purple

 

Check this out
YouTube - Royal Purple Synthetic Oil Explained

 

[QUOTE=TheNomad;6100304]I started using RP in my 79 after my brand new engine lifters started going out, it didnt stop them but the engine runs much smoother and cooler. So now I use it in all my trucks.
79 Ranger 03 Ranger and 94 Bronco RP for life.
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That was a very good clip on Royal Purple, and explains what many of us have been saying for a long time here.

Also, that Royal Purple clip also showed why using higher, thicker oil is not a good idea, with those tight tolerences in many modern engines. Oil that's supposed to flow quickly through there, and some want to add their dated, thick, oil to these engines?

No thank you.

There is another clip again showing how 5w30 oil can be used with confidence in engines that are stressed, towing, extended OCI's ect.

Thanks for that link. It confirmed what I've read and thought for a long time nicely.

 

pawpaw, or anyone else, I'd really like you to explain how oil can affect engine rpm at the same highway cruising speed. No way!