Motorcycle oil for automotive use

[RangerDan]

OK...hopefully I don't win the "Stupid Question of the Week Award"...but has anyone been using motorcycle spec oils for their cars?

For example, the Mobil 1 Product Guide lists their motorcycle oils at "1600 nominal phosphorus/zinc content"...compared to only around 800 for most of their automotive formulations. I realize that motorcycle oils lack Friction Modifiers due to wet clutch use...but then again most diesel oils don't use FM's either. There is also the "rumor" that the motorcycle Mobil 1's do actually have PAO still in them...

So what about a situation where you would mix three (3) quarts of automotive Mobil 1 5w-30 with two (2) quarts of 4TRacing 10w-40. Wouldn't this end up with a around a 6.5w-32.5, still have some FM's, end up with more EP additives, and maybe even a shot of POA. Lastly, Walmart's in SOCAL carry the Mobil motorcycle oils and doing the above "mix" would only add about $4 to the price of my oil change.

So is this a stupid idea or a valid one? Thanks in advance for the help!

RangerDan

 

[Audi Junkie]

From a non-technical perspective, no. PCMOs seem to formulated just fine. If you want a semi-synth, just buy $3-$4 oil and you will get a better product for a car. Is your car oil failing you somehow? fwiw, I use car oil in my motorcycle.

 

[RangerDan]

No failures...just looking for "added insurance". To give you a little background we "play" with both trucks and motorcycles out in the SOCAL deserts which can often be 100F+, deep sand (like dragging a boat anchor behind you), and remote areas (it's just no fun hiking out...).

We run a lot of the old air cooled XR Hondas on the Mobil 1 motorcycle oils and have noticed at oil change time that the oils are cleaner and actually have some viscocity left...some other oils at the same mileage have come out looking like "black water".

Since our trucks are out in this same environment, the thought of using this same motorcycle oil came up...and posted here for the experts!

RangerDan

 

[FrankN4]

If you want to stay in the 10W-30 range, you could just buy the Mobil 1 High Mileage 10W-30. It has 1000 PPM of ZDDP, an HTHS of over 3.5, exta detergents and antioxidents, full automotive friction modifiers, great 40C cSt and great 100C cst, yet still within the 10W-30 range.

I am not sure about the group III/group IV discussions but whatever Mobil 1 uses it has kept my Toyota running for 300,000 miles and my Cavalier, used every day, for 201,000 miles. Amsoil makes a series of oils called the XLT series and they are advertised as group III and they are great oils. The group IV has the natural advantage but the addative package becomes the equalizer, makes or breaks.

Just a personal note, and don't take it for anything more than that, for what you describe I would use a 10W-40 or, better yet, 15W-50. I have used only 15W-50 synthetic since 1990 in everything from little 1.5L 4 cyl up to large American V engines. Never a problem of any kind and no noticeable loss of gas mileage. Every car got/gets well above what the EPA estimate says.

 

[FrankN4]

I ran you mix through a calculator that I have and it gave the following results:
40C cSt.....72.6
100C cSt....12.2
VI..........166
ZDDP.......1120 PPM
HTHS........3.4

This is a very heavy 10W-30, just .3 cSt at 100C from being a 10W-40. You could run the M1 10W-40 High Mileage, still get 1000 ZDDP, a better HTHS, and the friction modifiers.

Please understand that many do not believe that FM are necessary and that they don't necessarily reduce wear. They can show used oil analysis for oils that have no FM and the wear will be as good as or better than oils with high FM. Now that I finally understand the place and purpose of FM, I want them in any oil that I use except for wet clutch motorcycles. THIS IS A PERSONAL PREFERANCE ONLY.

 

[Cmarti]

FrankN4, does the M1 HM have friction modifiers? I use the 10w 40 in one of my ATV/s that weeps around the jug. The 10W 40 is not Energy conserving, I do not know about the 10W 30.

 

[FZ1]

I think that motorcycle oils go in motorcycles and car oils go in cars. .02.

 

[artificialist]

But then I see numerous posts in the Motorcycle section where people have great success with CI4/SL and CJ4/SM oils, and wonder why not try it?

 

[FZ1]

True. Lot's of people run auto in bikes with no problems other than some reports of clutch slippage. I'm just more "in the box." Lol.

 

[FrankN4]

According to Mobil 1 tech services information, all Mobil 1 oils, including their diesel oils, do indeed have Friction Modifiers. The only exception to this is their raceing 4T 10W-40 and 20W-50 V Twin motorcycles oils which do not have friction modifiers.

Energy conserving, the starburst, is not just friction modifies, it is also viscosity requirements.

The main diffenence between motorcycle specific oil and automobile oils is that motorcycle oils do not have friction modifiers because the greater majority of them share the engine oil with the transmission and wet clutch. Friction modifiers can cause problems with slipage and engagement with wet clutches.(I just learned in the past year that there are "special" motorcycle oil friction modifiers that do not efect the wet clutch) Some motorcycles have seperate engine, clutch, and transmission oil supplies. Many folk that have these bikes, most noteably Harley Davidson, use a high FM oil in the engine, a non FM oil in the primary drive and clutch, and another with anti wear and extreme pressue additives in the transmission. Motorcycle specific oils usually have much higher ZDDP levels because of the wear potential of gear teeth against gear teeth in the shared transmissions. These gears will also sheer oil much more severely and quickly than an automobile that has no or very few gears in the engine. Motorcycle oils need to be very sheer stable.

There is a rather long thread here about friction modifiers. It is a few pages over and it was started by me. if you read those threads carefully and follow all the links, you will learn much about friction modifiers and can decide for yourself how important they are or are not for you.

 

[RangerDan]

Thanks everyone for the help...

RangerDan