help with 15w-50 M1
- Thread starter JonS
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Don't have your answer but it's good question. Think it's funny because a buddy of mine races Jaguar and uses one of the most notable Jag engine builders in the world. When you pay the fortune they do for motors you use what the engine builder says for oil. He runs mobile 1 15w50, has for years. Last time I was at his shop I asked if he knew the formulation has changed a few times. Nope, never heard about it. Told me latter his builder didn't know either. Just goes to show even the engine builders that are on top of their game know little about oil. Conversely many oil experts and chemists know little about engines.
IIRC, the gold cap is the extended service stuff and the silver cap is the old red cap. Read the back label carefully.
Lately all I've seen is the gold cap 15w/50, which is what I'm using in my Nighthawk until the end of this year, when I'm switching it over to Rotella T 5w/40. I've been using the red cap stuff for 8 years, and the gold cap for almost 2.
I have not seen a UOA or VOA on the silver cap yet. But Mobil suggested this version of 15-50 for my custom turbo Miata. They do not suggest the gold cap. In addition, I believe the gold cap was responsible for a recent turbo failure on my car.
Still, the gold cap oil did not coke up in the high boost turbo application. It was low on oil pressure under very high temp conditions and the result was turbo bearing failure. But keep in mind that the lower oil pressure was catastrophic only because the turbo has a restriction orifice.
What does this mean for motorcycles? High temp air cooled engines would probably be better served with Mobil 1 motorcycle specific oil (group IV-V), as it is not a group III oil. Water cooled bikes with should be fine with the Gold cap.
The silver cap is still an unknown in my mind, but if it is similar to the old red cap, it should be fantastic.
Chris
Still, the gold cap oil did not coke up in the high boost turbo application. It was low on oil pressure under very high temp conditions and the result was turbo bearing failure. But keep in mind that the lower oil pressure was catastrophic only because the turbo has a restriction orifice.
What does this mean for motorcycles? High temp air cooled engines would probably be better served with Mobil 1 motorcycle specific oil (group IV-V), as it is not a group III oil. Water cooled bikes with should be fine with the Gold cap.
The silver cap is still an unknown in my mind, but if it is similar to the old red cap, it should be fantastic.
Chris
Highly doubt there is enough of a difference in the Extended Performance to be the reason for your turbo failure. If that were truely the case you would have a liability issue with either the dealer since Mobil-1 15w50 grade is recommended.
resslera, my turbo setup is a custom race car setup. It has nothing in common with any production or "kit" turbo system.
I run very high boost, sometimes over 30PSI. The car is used at track events (road race) and has been quite a "test bed" for oil and bearings.
In short, the red cap was sufficient to protect if short OCI's were observed.
My experience with thinner oils was not positive.
I run very high boost, sometimes over 30PSI. The car is used at track events (road race) and has been quite a "test bed" for oil and bearings.
In short, the red cap was sufficient to protect if short OCI's were observed.
My experience with thinner oils was not positive.
Chris,
Seems that the F1 crowd is leaning towards thinner viscosities.
You know as well as I do that blaiming a failure on a particular oil is a stretch. Especially when the oil used is so very close to the same formulation as the fluid the mfg recommends.
I have trusted many of your observations over the years, but this one I gotta take issue with. The only difference in the two fluids is a boost of the add pack, and that is the oil you are blaming for causing your turbo to fail.
There has to be a deeper root.
Seems that the F1 crowd is leaning towards thinner viscosities.
You know as well as I do that blaiming a failure on a particular oil is a stretch. Especially when the oil used is so very close to the same formulation as the fluid the mfg recommends.
I have trusted many of your observations over the years, but this one I gotta take issue with. The only difference in the two fluids is a boost of the add pack, and that is the oil you are blaming for causing your turbo to fail.
There has to be a deeper root.
Jaybird,
The OEM oil was 10-30. Not really that close to the 15-50, or am I missing something? The OEM redline was 6800. I currently run the engine to 8K. There was no turbo in stock form. I am not sure what you are trying to say? Maybe you were thinking my car was a stock turbo system?
In any case, I am correct, the gold cap was not able to maintain oil pressure when hot. No stretch there, just simple facts. The red cap did better, and the silver cap remains to be seen. So far, the silver cap is OK in my car.
By the way, those with similar turbo miata to mine have the very same issues. I am not alone. Thin oil may be better in other turbo engines. Not this one. The big issue is con rod bearings. Thin oil results in 250+ppm lead. CR bearings last a year with thin synthetics in a turbo miata.
I do not have all the answers, like you, I am here to learn and share what I think I know. I was trying to be careful to "apply this to motorcycles".
Chris
The OEM oil was 10-30. Not really that close to the 15-50, or am I missing something? The OEM redline was 6800. I currently run the engine to 8K. There was no turbo in stock form. I am not sure what you are trying to say? Maybe you were thinking my car was a stock turbo system?
In any case, I am correct, the gold cap was not able to maintain oil pressure when hot. No stretch there, just simple facts. The red cap did better, and the silver cap remains to be seen. So far, the silver cap is OK in my car.
By the way, those with similar turbo miata to mine have the very same issues. I am not alone. Thin oil may be better in other turbo engines. Not this one. The big issue is con rod bearings. Thin oil results in 250+ppm lead. CR bearings last a year with thin synthetics in a turbo miata.
I do not have all the answers, like you, I am here to learn and share what I think I know. I was trying to be careful to "apply this to motorcycles".
Chris
My mistake was seeing "Mobil recommended" and thinking the "engine oem recommended"...
I find it very interesting that the Mobil1 EP formulation was thinning so much at high temps, yet the other formualtion didn't. This would indicate some differences in bases.
I think this situation falls in line with many of the observations that Dr Haas has made. I think I need to go back and re-read some of his stuff.
Btw..I was in no way trying to put down any of your information, as I too am here for the same reasons you are.
And I think your info is quite pertinent...I just want to understand what we are seeing with your application.
ps...is your race fuel leaded?
I find it very interesting that the Mobil1 EP formulation was thinning so much at high temps, yet the other formualtion didn't. This would indicate some differences in bases.
I think this situation falls in line with many of the observations that Dr Haas has made. I think I need to go back and re-read some of his stuff.
Btw..I was in no way trying to put down any of your information, as I too am here for the same reasons you are.
And I think your info is quite pertinent...I just want to understand what we are seeing with your application.
ps...is your race fuel leaded?
There aren't too many oils that work in motorcycles see the uoa's. Thin oils are not the answer in all cases . Cujet your engine is being pounded more than a stock engine.so stuff will happen. More pressures = more wear. Is the restriction orfice to reduce oil pressure to the turbo seals?
Is the restriction orfice to reduce oil pressure to the turbo seals? Yes, it eliminates exhaust smoke.
I use 93 octane pump unleaded with 20% toluene. It is enough for any boost level I will ever run. Leaded fuel would help valve seat life in some engines run to very high RPM, However I do not use leaded fuel.
On 4 stroke dirt bikes, I do use 100LL mixed at 50% from time to time.
Chris
Chris
I use 93 octane pump unleaded with 20% toluene. It is enough for any boost level I will ever run. Leaded fuel would help valve seat life in some engines run to very high RPM, However I do not use leaded fuel.
On 4 stroke dirt bikes, I do use 100LL mixed at 50% from time to time.
Chris
Chris
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