Diesel oils in gasoline engine

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Miles Long

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Hi folks -
I've used Rotella 15-40 regular oil in all my engines (car, bikes, snowblower, etc.,) for years. All has been well, to date.
Now I see that Canadian Tire has their Rotella T15-40 DIESEL on sale - $68 cdn. for a 18.9 liter pail (with the current exchange, that works out to 25 cents/liter American:biglaugh:)

Anyway, I searched the database high and low, couldn't find a thing about oils to use in the Max:biglaugh::biglaugh::biglaugh:
Seriously, very little about regular versus diesel oils in a gasoline engine.
But I did find one man's opinion on the Net.

What say you about this, Max owners???
Cheers!

Diesel Oil Not Good For Gas Engines
November 5, 1986|By Bob Sikorsky
Dear Bob: Several friends of mine believe that using diesel oil in gasoline engines makes the engines last longer. They support this by saying that diesel oil works in harsher conditions -- higher temperatures and longer trips -- than oil for gasoline engines. Which oil is best for my car? And which multigrade oil -- 10W-40 or 20W-50 -- is best for areas where summer temperatures are high? Your column is much appreciated here in Mexico. -- M.A.L.

Dear M.A.L.: Logic would indicate that your friends` reasoning is correct. Diesel oils have to put up with much higher engine temperatures, higher oxidation rates, sulfur deposits, fuel soot, acids and other deposits and conditions not usually found in automobile engines. So it would make sense that using diesel oil in a gasoline engine would enhance the latter`s longevity.

Uh-uh!

Oils meant for use only in diesels are rated by the American Petroleum Institute as CC, CD or CC/CD. These letters on the oilcan indicate that the oil is specifically formulated for diesel engines.

If you happen to be driving a new car -- diesel-engine cars excepted -- nowhere in the owner`s manual will you see recommended a CC, CD or CC/CD oil. All current gasoline engines require an SF oil. The SF can be in combination with CC or CD or even CC/CD -- for example SF-CC/CD -- but you will never see just CC or CD recommended.

If diesel oils are so good, why don`t car manufacturers recommend their use in gasoline engines? It`s because diesel oils fail in one critical area when used in gasoline engines. API-rated diesel CC or CD oils do not meet the engine-cleanliness parameters set for oils rated SF for gasoline engines.

As you say in your letter, diesel engines are used under prolonged running conditions and higher temperatures, while cars with gasoline engines are driven a lot in stop-and-go traffic.




These different driving conditions, along with the great difference between diesel fuel and gasoline, mean that different engine deposits must be controlled in the individual engines.

What will keep a diesel engine clean fails to do the job in a gasoline engine because the deposits are different, the fuel is different, the running conditions are different, and the oil`s additive package is different.

As for your second question, I would use higher viscosity 20W-50 oil in the summer and switch to 10W-40 for winter use. It does make a difference.
 
Clean engine oil won't be a problem and I don't believe that there is a deposits issue myself. But, everyone has an opinion.
 
Hi folks -
I've used Rotella 15-40 regular oil in all my engines (car, bikes, snowblower, etc.,) for years. All has been well, to date.
Now I see that Canadian Tire has their Rotella T15-40 DIESEL on sale - $68 cdn. for a 18.9 liter pail (with the current exchange, that works out to 25 cents/liter American:biglaugh:)

Anyway, I searched the database high and low, couldn't find a thing about oils to use in the Max:biglaugh::biglaugh::biglaugh:
Seriously, very little about regular versus diesel oils in a gasoline engine.
But I did find one man's opinion on the Net.

What say you about this, Max owners???
Cheers!

Diesel Oil Not Good For Gas Engines
November 5, 1986|By Bob Sikorsky
Dear Bob: Several friends of mine believe that using diesel oil in gasoline engines makes the engines last longer. They support this by saying that diesel oil works in harsher conditions -- higher temperatures and longer trips -- than oil for gasoline engines. Which oil is best for my car? And which multigrade oil -- 10W-40 or 20W-50 -- is best for areas where summer temperatures are high? Your column is much appreciated here in Mexico. -- M.A.L.

Dear M.A.L.: Logic would indicate that your friends` reasoning is correct. Diesel oils have to put up with much higher engine temperatures, higher oxidation rates, sulfur deposits, fuel soot, acids and other deposits and conditions not usually found in automobile engines. So it would make sense that using diesel oil in a gasoline engine would enhance the latter`s longevity.

Uh-uh!

Oils meant for use only in diesels are rated by the American Petroleum Institute as CC, CD or CC/CD. These letters on the oilcan indicate that the oil is specifically formulated for diesel engines.

If you happen to be driving a new car -- diesel-engine cars excepted -- nowhere in the owner`s manual will you see recommended a CC, CD or CC/CD oil. All current gasoline engines require an SF oil. The SF can be in combination with CC or CD or even CC/CD -- for example SF-CC/CD -- but you will never see just CC or CD recommended.

If diesel oils are so good, why don`t car manufacturers recommend their use in gasoline engines? It`s because diesel oils fail in one critical area when used in gasoline engines. API-rated diesel CC or CD oils do not meet the engine-cleanliness parameters set for oils rated SF for gasoline engines.

As you say in your letter, diesel engines are used under prolonged running conditions and higher temperatures, while cars with gasoline engines are driven a lot in stop-and-go traffic.




These different driving conditions, along with the great difference between diesel fuel and gasoline, mean that different engine deposits must be controlled in the individual engines.

What will keep a diesel engine clean fails to do the job in a gasoline engine because the deposits are different, the fuel is different, the running conditions are different, and the oil`s additive package is different.

As for your second question, I would use higher viscosity 20W-50 oil in the summer and switch to 10W-40 for winter use. It does make a difference.

Ok Miles then lets go 1 step further & not directed at you just making a point. But a motorcycle Eng. oil has a trans & clutch to deal with. :ummm:

Dave
 
That sounds like a post by bob the oil guy. Most of his stuff I agree with....some I dont. I think the addition of wet clutches are what makes the big difference for Vmaxxes vs automobiles.

In my car.....the manufacturer recommends 0-20w.....for energy conserving. I wouldnt put that in a bike.
 
Ok Miles then lets go 1 step further & not directed at you just making a point. But a motorcycle Eng. oil has a trans & clutch to deal with. :ummm:

Dave

Yup. The wet clutch is the reason new oil in the crankcase will turn so black, so quick, That's my theory, and I'm sticking to it!
However, the V-max service specifications call for a "high quality detergent engine oil, with an API classification of SE, SF or SG" (SF being mentioned in the above article, dealing with car oils)
NO mention is made about using motorcycle-specific oils, which may or not (??)contain additives to alleviate any negative effects of clutch plate material floating around in it.
I can only conclude that clutch wear doesn't effect the lubrication qualities of oil (regular or diesel),used in motorcycles.
But getting back to the original question and article quote, the author is suggesting that diesel oil doesn't have the needed properties to be effective in gasoline engines, hence the different classfication letters.
To be on the safe side, I'll continue to use SF oils, regardless of any sales I run across for diesel types.
Like so many have said previously, the most important issue is changing the oil regularly.
Cheers!
 
Bob is referring to oil for diesels only isn't he? RotellaT 15W-40 isn't diesel only I don't believe.

EDIT: Rotella claims Their RotellaT meets the requirements of JASO & MA....I doubt they'd make that statement without knowing it to be true....probly just didn't want to go to the expense of the actual certification process.
 
Isn't it the friction modifiers added to the oil which make the car oil not suitable for the wet clutch engines? Like ZDDP which I have read is good in moderate amounts added in the oil formulation, but none or too-much may be harmful?

Here is one source I found: http://www.bmwmotorcycletech.info/oilessay.htm

I sent time to read the entire article. There is much info to digest here, incluing an article section sure to provoke much discussion among those who swear-by K&N air filters. The author relies on specific lab tests to gauge the effectiveness of the surgical gauze/Stainless Steel K&N and compares it to a stock pleated paper element air filter. The discussion is about BMW's both air cooled and water cooled. No reason why the discussion couldn't be considered appropriate to thhe VMax. I appreciate that instead of going by what is called 'anecdotal evidence,' (what happened to you and your bike, using or not using the product in question) there are SAE type quantitative testing techniques done and results posted. What does this have to do w/oil discussions? Excessive particulate matter passed through the engine causes increased wear, and contaminates the oil. Failure to change oil or air filters, or to clean the reusable type, is not good for the engine.

Oil filters are also discussed. All in all there is a lot of good info backed by facts and not marketing.
 
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Isn't this why we like running the 15w40 rotella....the zinc or any brand with ci-4 plus

existing CI-4+ rated Rotella oil. This is achieved despite a lower zinc and phosphorus additive level as called for by the API CJ-4 specification. (The 15W-40 Rotella T with Triple Protection oil has approximately 1200 ppm of zinc and 1100 ppm phosphorus at the time of manufacture.)
 
The DIESEL oil is NOT designed to rev 9, to 11 rpms. It will cavitate and you Will get engine damage. It belongs in diesel motors, not bikes.
 
Around the time I bought my 89 Vmax(12 yr.s ago), I was working at a marina where all gas engines got 15w-40 Rotella, unless the customer wanted Mercury or Yamaha oil, which cost more than double. It always a source of amusement between mechanics. Most mid sized diesel engines also got the Rotella treatment. We'd wheel a 50 gallon drum down to the boat and get to keep what was left, usually a couple of gallons per boat. I had a good supply and was changing every thousand miles. That is something I'd only do when oil is free.The first thing I noticed was how nice my bike went into neutral with Rotella, and how smooth it shifted. I never wanted to buy anything else. Like Eric mentioned, cars are specked out for much lighter oils now. Rotella is good stuff. IMO.
 
The DIESEL oil is NOT designed to rev 9, to 11 rpms. It will cavitate and you Will get engine damage. It belongs in diesel motors, not bikes.

I can only attest to my own 54k vmax engine hitting red line on a regular basis. Rotella is also the most popular oil used on this forum as far as I know. You might wast to skim through the many threads on the subject here. If your new, read the endless threads on this before deciding.
 
Bob is referring to oil for diesels only isn't he? RotellaT 15W-40 isn't diesel only I don't believe.
Correct, Dan.

Rotella T 15-40 for gasoline engines
" " " " diesel engines
Clearly marked on the containers.
It's the diesel version that's on sale now, and that I've decided NOT to buy.
Check out Mr. Jinks opinion!
Cheers!
 
I can only attest to my own 54k vmax engine hitting redline on a regular basis. So throwing that out there to the new guys is hmmm.
uhm00000.gif

Its for low revving engines not high performance high revving engines.
 
I'm in trouble then.....the 80 to 90 dyno runs with Rotella T have put the bike on its last legs then. Oh......and I have about 44k miles on the bike.

Sent from my SCH-R890 using Tapatalk
 
Like otthers have said, T6 Rotella is JASO MA certified, I run it in my Blackbird and the Max. I wouldn't be concerned about the RPM's and thrashing, a lot of diesel applications have high pressure/high volume oil pumps that can get up to 2500 psi that actuate injectors, etc that pretty well exceeds the demands of our little motors.
 
I'm in trouble then.....the 80 to 90 dyno runs with Rotella T have put the bike on its last legs then. Oh......and I have about 44k miles on the bike.

Sent from my SCH-R890 using Tapatalk

I thought we were talking about Car or truck oil. sorry,...Yes rotella does make an excellent motorcycle oil. When I hear the word Diesel, I just think of heavy duty applications in the industrial field. Sorry for the confussion,..was not aware we were talking motor oil designed for bikes.
 
I thought we were talking about Car or truck oil. sorry,...Yes rotella does make an excellent motorcycle oil. When I hear the word Diesel, I just think of heavy duty applications in the industrial field. Sorry for the confussion,..was not aware we were talking motor oil designed for bikes.

Thats ok....even with different topics....the focus always comes back to the mighty Vmax.:punk:
 
I thought we were talking about Car or truck oil. sorry,...Yes rotella does make an excellent motorcycle oil. When I hear the word Diesel, I just think of heavy duty applications in the industrial field. Sorry for the confussion,..was not aware we were talking motor oil designed for bikes.

He is talking about the inexpensive Rotella T you can get at Walmart. We've used in many vmax's with many different engine configurations and power levels. Your statement about it not working for hi revving engines (which I suspect you have no proof of testing to verify) does not match our experience with the product in real world testing.

Sean
 
He is talking about the inexpensive Rotella T you can get at Walmart. We've used in many vmax's with many different engine configurations and power levels. Your statement about it not working for hi revving engines (which I suspect you have no proof of testing to verify) does not match our experience with the product in real world testing.

Sean

Your right for sure. I guess I'm kinda out the "oil" loop. I'm still thinking dino diesel, LOL. Its amazing how far oils have come recently.
 

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