Motorcycle oil in a diesel?

[shakescreek]

Not sure if this is in the right section for this question but I have a light duty diesel that sees pretty heavy duty use so this seems as good as anywhere. The engine in question is a 1.9 vw pd(unit injectors) tdi that I have in a welded aluminum jetboat. The engine was rated 160hp stock but I have pumped it up to about 230 hp with larger turbo and remapping. In my application the engine sometimes runs at constant 3200rpm for 4 to 5 hours at a time at which speed the impeller is absorbing 130 hp. This is much higher stress than it would ever be likely to see in a car. I have about 2000 hours on it so far in this use and so far have been running mainly redline 15-40 diesel motor oil on 200 hour oci's. I have been considering switching to the redline 10-40 motorcycle oil on the next oil change. I know the motorcycle oils have to be designed for use with wet clutch systems, so my question is would there be anything added for the motorcycle clutches and transmissions that would make it unsuitable for use in a diesel engine? What I like about the 10-40 motorcycle is it has quite a bit more zinc, phosphorous, and moly in it, 2125-2100-425 vs 1225-1206-120 for the 15-40. It also has a slightly better noack at 5 vs 6 for the 15-40. HTHS is the same for both at 4.7 and vis@100 is the same at 14.5.
So does any one have any thoughts as to whether there would be any downside other than slightly higher cost to switching to the 10-40?

 

[CleverUserName]

In before the slew of members telling you to use a Low Saps 507 oil in this diesel...

Is this 10w40 a low detergent oil since it is for racing? If so, probably not good unless you plan on changing it every time it’s out on the water.

Do you really need 2000+ ppm of phoshourus? Reason I ask is there are a number of diesel specific oils available which have ~ 1500 ppm phosphorus with good detergency. Amsoil makes a new high zinc racing 20w50 and their old cI-4+ Oils SAE 30, 10w40, 20w50 and 15w40 are excellent with ~ 4% NOACK.

 

[FermeLaPorte]

I would keep using it since it's working but I wouldn't give it a long oci just for peace of mind

 

[Kamele0N]

How are your camshafts looking and tappets? Since its PD engine wich needs vw 505.01 OR vw 507 oil with special EP/AW additive in it...

 

[JAG]

That is a demanding application. With diesel engines, the oil’s ability to finely disperse the spot is very important for wear control. Detergent and dispersant additives do that. The 15W-40 Red Line may be better than the motorcycle oil in that regard. What I would do:
- Ask Dave, at Red Line for his opinion
- Install a by-pass oil filter
- Do UOAs

 

[Olas]

Any xw40 from redline will be fine, as will any 505.01 approved lube.

 

[krismoriah72]

Rotella 15w40 or 5w40

Proven in motorcycles, atvs, utvs, as well as diesel engines all over the world on land and sea. Not to mention OPE and generators.

 

[racin4ds]

I'd honestly stick with what you're using. You're running the snot out of that little TDi and it needs a good, syn diesel rated oil. My bet is if you change to something inferior it won't last long...

 

[shakescreek]

Redline does not class the 10-40 motorcycle oil as a racing oil and they state it is good for "Extended drain intervals over other brands due to higher quality base stocks and excellent dispersants ", although I'm not sure what extended drain intervals really means in the context of motorcycle use. Which additives are used for soot control? Does anyone know what additives are added for wet clutch systems and what there effect would be in a diesel? I did call Redline and talk to Dave. He recommended I stay with the 15-40 due to higher tbn, but he kind of beat around the bush and never really answered my question about wet clutch additives. Is tbn likely to be an issue with 200 hr oil changes and modern ulsd fuel? UOA's would be difficult for me to due due to my remote location, as ups, purolator, loomis, ect do not serve this area, and the post office wont accept motor oil. I do run an amsoil bypass filter on the engine.

 

[Elgouyo]

In my opinion, these two oils may be good for this marine application.
I couldn't find Redline 10-40's TBN. High TBN should be suitable in case of high sulfur diesel gas use.
In case of wet clutch system, there should be less 'slippery' additives, like friction modifiers. Nevertheless, many motorcycle oils contain friction modifiers. For exemple, Red Line Motorcycle 10w-40 oil contains 425 ppm of Moly. In my opinion, this motorcycle oil has far stronger base oil than any car-designed 10w-40.
On tdiclub forums, I read that Pump-Düse TDI had good results too with Top-Tier Diesel Truck oils, like Rotella.

Just to figure out how this engine lives hard times, could you tell me its oil and water temperatures ? How is it cooled ?

 

[shakescreek]

Pretty much unlimited cooling is one advantage of the marine environment. My engine coolant flows through a tube type heat exchanger with river water cooling it and stays very close to 90*C no matter the load. The engine has the stock oil cooler on it which in the stock configuration has the 90* coolant flowing through it to cool the oil, but I have replumbed it to have the raw river water through it. The river is glacial water so is never more than a few degrees above freezing. I don't have an oil temp gauge on it, but after hours of hard running I can keep my hand on the oil filter housing not indefinitely but for quite a while(probably 15 or 20 seconds) before it becomes uncomfortable enough to want to let go. Intake air is cooled post turbo with an air to water intercooler with glacial water through it and keeps intake air temps in the single digits even at high boost. I run about 32 psi of boost at cruise speed to keep egt's down to about 950-1000*F.

 

[CleverUserName]

Originally Posted By: shakescreek
Redline does not class the 10-40 motorcycle oil as a racing oil and they state it is good for "Extended drain intervals over other brands due to higher quality base stocks and excellent dispersants ", although I'm not sure what extended drain intervals really means in the context of motorcycle use. Which additives are used for soot control? Does anyone know what additives are added for wet clutch systems and what there effect would be in a diesel? I did call Redline and talk to Dave. He recommended I stay with the 15-40 due to higher tbn, but he kind of beat around the bush and never really answered my question about wet clutch additives. Is tbn likely to be an issue with 200 hr oil changes and modern ulsd fuel? UOA's would be difficult for me to due due to my remote location, as ups, purolator, loomis, ect do not serve this area, and the post office wont accept motor oil. I do run an amsoil bypass filter on the engine.


Calcium / magnesium are dispersants and primarily used for soot control. The CI-4+ was heavy on the calcium, then many of the newer formulations in CJ-4 and CK-4 started using a higher % of magnesium.

Not sure what addives are used for wet clutch applications. Since the RL 15w40 has a higher TBN I would guess it has more calcium than the motorcycle oil in question. Most RL oils I’ve seen are weak on magnesium and primarily use calcium as the detergent/dispersant additive.

You could also get some of the RL ZDDP concentrate and add it to the 15w40 to get you where you want it to be. A can of Liqui Moly 2009 Mos2 would also give you another 300+ ppm of molybdenum.

 

[Hammehead]

Bike oils also have a good ammount of dispersants to cope with the insolubles from the clutch wear. Nonetheless, bike oils have to have pretty nice Viscosity Index Improvers to withstand the hot gear meshing. So, I´d say bike oils are as good or even better than HDEO in the viscosity stability regard. I feel that you´re preocupied with viscosity maintenance from its severe use.

 

[jongies3]

I guess I don't see the benefit in paying extra for motorcycle oil when any quality brand HDEO will do the job for a lot less?