Jump to content
IGNORED

Moly grease for spline lubes - specs?


SWB

Recommended Posts

Have been told that the lubricant of choice for BMW drive splines is Honda's "Moly 60". I picked some up, but then found a can of "Coastal Industrial Moly EP Grease" in our petroleum products. Is this an equivalent product, or will it suffice. Anyone know the specs?

 

This product:

 

Lithium 12 hyroxy extreme pressure grease

Contains molybdenum disulfide

Water insoluble

Contains polyethylene for superior film strength

Antiwear, antirust, antioxidant

Recommended for NLGI No. 2 multi-purpose applications (auto chassis, wheel bearings, u-joints.

Satisfactory performance where Ford ESA MC75B and Mack Multi-Purpose MG-C is recommended.

 

Does that sound close, or should I stick with the Honda grease and add yet another opened tube stuff to my storage shelves.

Link to comment

The Honda Moly 60 is 60% molydimum (sp?) the plain vanilla moly grease for lube has well under 10% and is much less viscous (more runny). The Honda moly or indeed the castrol version used by BMW has the consistency of toothpaste and will not fling off, the other is, well just grease.

 

Put the can on your shelf and get either Honda moly 60 or the castrol optimol T as specified by BMW.

 

Andy

Andy

Link to comment

I went thru the same thinking. I have all types of Moly greases as work. I decided to buy the Honda grease since it was $10, and I would not have to think twice about it after I did the job.

 

The tube that I got is one of those mini grease gun tubes.

Link to comment
I went thru the same thinking. I have all types of Moly greases as work. I decided to buy the Honda grease since it was $10, and I would not have to think twice about it after I did the job.

 

The tube that I got is one of those mini grease gun tubes.

 

Well, my original line of thinking matched yours...what's $13 when I'm spending $2500 in other parts and repairs. Then my bright 19 year old son pulled a can of thick moly paste off the shelf and asked "why'd you buy more lub, Dad"? Since he's much smarter than I am in just about every area of life (or so he regularly assures me), I started thinking that I might be just duplicating supplies we already have once again (you know, 3 cans of WD-40, 3 half used cans of Carb cleaner, etc.).

 

But, my son ain't that smart (he'll learn that if he lives to the age of 25; I did. grin.gif), and I don't want to R&R the transmission on this bike again in my lifetime. So, Honda moly it is.....

 

Thanks.

Link to comment
I went thru the same thinking. I have all types of Moly greases as work. I decided to buy the Honda grease since it was $10, and I would not have to think twice about it after I did the job.

 

The tube that I got is one of those mini grease gun tubes.

 

Well, my original line of thinking matched yours...what's $13 when I'm spending $2500 in other parts and repairs. Then my bright 19 year old son pulled a can of thick moly paste off the shelf and asked "why'd you buy more lub, Dad"? Since he's much smarter than I am in just about every area of life (or so he regularly assures me), I started thinking that I might be just duplicating supplies we already have once again (you know, 3 cans of WD-40, 3 half used cans of Carb cleaner, etc.).

 

But, my son ain't that smart (he'll learn that if he lives to the age of 25; I did. grin.gif), and I don't want to R&R the transmission on this bike again in my lifetime. So, Honda moly it is.....

 

Thanks.

 

I have 3 cans of WD40 as well - each of them with a different amount in them grin.gif

 

I also have 3 or 4 different moly lubes, 2 wheel bearing greases, and all different types of spray lubes (CRC, Boeshield, PB blaster, etc).

 

I thought the same thing - WTF do I need another opened container of grease? Between what I have at home and what I have at work, there should be something!

 

I knew what would have happened if I used the Molykote® stuff from work, I would have worried I used some infeior product (even though this stuff is nuclear grade lube), and done the job over again with Honda moly wink.gif

 

I am the f-ed up crazy.gif

Link to comment

Don't use it!!!

 

The phrase "Contains Molybdenum Disulphide" means, when translated, it has a small amount of the stuff in it somewhere.

 

BMW's spec calles out for a moly grease made by Staburags that contains a very high percentage of MoS2, on the order of 60% or more.

 

The actual type of grease "carrier" is irrelivant. What matters is that you MUST have high MoS2 content, because it is the Moly high pressure solid lubricant that is stopping your splines from destroying themselves, not the grease it is mixed in with.

 

There are lots of suitable moly greases out there, but most are sourced from industrial suppliers. An example of this is Dow Corning's "Gn Paste" which works well, but you need to find a Dow Corning industrial supplier.

 

Honda's Moly 60 is easily available and relatively cheap. Use it!

Link to comment

I agree with all of the above except for

 

"The actual type of grease "carrier" is irrelivant"

 

greases perform differently under various conditions

Link to comment
Personally, I recommend Dupont Krytox 227 for the spline lube application - check out the specs >>HERE<<<.

I wouldn't touch this stuff with the proverbial 10 foot pole! It has no Moly in it at all as far as I can see. The purpose that this grease was created for (Extremely high and low temperatures) has nothing whatsoever to do with the requirements of driveshaft lubrication.

 

BMW states very clearly that a grease with high MoS2 content is mandatory. This Dupont grease has none. Why in heaven's name would you use a grease that has no moly in it (thus violating BMW's requirements), and is mainly formulated to excel in temerature extremes that will never occur in driveshaft lubrication use? This makes no sense!

 

Nothing on this earth is a better extreme pressure lubricant than Molybdenum Disulphide. The fluorocarbons (relatives of Teflon) that this Krytox grease contains do not even come close to moly in this respect. Their main claim to fame is that they remain stable at hundreds of degrees. How is that useful in this application??

Link to comment
Don_Eilenberger
Well, my original line of thinking matched yours...what's $13 when I'm spending $2500 in other parts and repairs. Then my bright 19 year old son pulled a can of thick moly paste off the shelf and asked "why'd you buy more lub, Dad"? Since he's much smarter than I am in just about every area of life (or so he regularly assures me), I started thinking that I might be just duplicating supplies we already have once again (you know, 3 cans of WD-40, 3 half used cans of Carb cleaner, etc.).

 

But, my son ain't that smart (he'll learn that if he lives to the age of 25; I did. grin.gif), and I don't want to R&R the transmission on this bike again in my lifetime. So, Honda moly it is.....

 

Thanks.

Correct - your son isn't THAT smart - besides the moly in Honda-Moly60 - the carrier grease is also important. If there isn't a good carrier grease - the moly will not protect your splines.

 

BTDT on one set of splines with some moly based 3M "Assembly Paste" - had about 90% moly in it. More was NOT better in this case. There was some significant wear on the splines next time I opened it up.

 

The big pluses to Honda Moly60 are:

 

o - Cheap (cheapest thing on a BMW is..?)

 

o - Well tested by the BMW community for this application (I was one of the original "spline-lube-gang" who tried all sorts of lubes with varying success.)

 

o - Designed for the application - it's made for Goldwing splines.

 

There have been no reports of spline damage that can be attributed to the use of the Honda product that I know of. There has been damage even when using it - but in these cases - it has turned out to be an alignment problem, not a lube problem.

 

Just a FWIW: Also - worth considering - is Wurth-3000 lube and RedLine Synthetic Moly grease. Both have been used with good results on K75's - which seemed the most problematical for spline problems.

 

The Wurth-3000 is an exceptionally sticky grease - it has the tenacity of chewing gum. The RedLine appears to be a moly variant of some sort. Comes out of the tube red, when it is "worked" (in the splines under use) - it turns black.

 

I have all of these on my shelf at home.. and have used all of them at some time on the splines on various bikes. I still would reach for the Honda-Moly60 if I was doing my own bike.

Link to comment
I agree with all of the above except for

 

"The actual type of grease "carrier" is irrelivant"

 

greases perform differently under various conditions

Agreed. But the actual "grease" in this application is not what provides any significant protection against fretting wear in the splines. It is the MoS2 that is doing the job, namely preventing metal to metal wear under extremely high contact pressure, between splines that barely move at all.

 

Remember, that in this situation, we have the worst lubrication problem possible, namely that two metal surfaces are pressed against each other with pressures of thousands of psi, while they rapidly move only very slightly against each other. The speed and magnitude of movement is not enough to allow an oil or grease film to build up between them, so without a solid lubricant to bond to the teeth faces, the constant near microscopic movement between faces causes them to wear away. This is termed "fretting wear".

 

Therefore, in this situation, what matters is the moly content, and quality. The grease is just holding the moly together, and keeping it in place for long enough for it to get burnished into the surface of the splines during initial operation after a new lube has been performed. Once that has taken place, the grease does very little (in fact, it is squeezed right out of the high pressure contact area). The moly is now burnished onto the spline teeth and stays there, providing a microscopic solid barrier against metal-to-metal contact.

Link to comment
I agree with all of the above except for

 

"The actual type of grease "carrier" is irrelivant"

 

greases perform differently under various conditions

Agreed. But the actual "grease" in this application is not what provides any significant protection against fretting wear in the splines. It is the MoS2 that is doing the job, namely preventing metal to metal wear under extremely high contact pressure, between splines that barely move at all.

 

Remember, that in this situation, we have the worst lubrication problem possible, namely that two metal surfaces are pressed against each other with pressures of thousands of psi, while they rapidly move only very slightly against each other. The speed and magnitude of movement is not enough to allow an oil or grease film to build up between them, so without a solid lubricant to bond to the teeth faces, the constant near microscopic movement between faces causes them to wear away. This is termed "fretting wear".

 

Therefore, in this situation, what matters is the moly content, and quality. The grease is just holding the moly together, and keeping it in place for long enough for it to get burnished into the surface of the splines during initial operation after a new lube has been performed. Once that has taken place, the grease does very little (in fact, it is squeezed right out of the high pressure contact area). The moly is now burnished onto the spline teeth and stays there, providing a microscopic solid barrier against metal-to-metal contact.

 

True - however the grease has to be able to withstand the temp, friction, and RPM (slinging) to hold the moly in place long enough for it to be burnished into the surface.

 

BTW - I have heard others using that Krytox as well. I use Krytox 240 at work with space applications. It has the consistency of a heavy hand lotion. I personally dont like that stuff for any use. It seems to dry out and almost crystallize.

 

We have some MoS2 powder that I was considering using to make my own brew of moly grease. But after having the Honda stuff available at the place right up the street, I figured why reinvent the proverbial wheel grin.gif

Link to comment
I agree with all of the above except for

 

"The actual type of grease "carrier" is irrelivant"

 

greases perform differently under various conditions

Agreed. But the actual "grease" in this application is not what provides any significant protection against fretting wear in the splines. It is the MoS2 that is doing the job, namely preventing metal to metal wear under extremely high contact pressure, between splines that barely move at all.

 

Remember, that in this situation, we have the worst lubrication problem possible, namely that two metal surfaces are pressed against each other with pressures of thousands of psi, while they rapidly move only very slightly against each other. The speed and magnitude of movement is not enough to allow an oil or grease film to build up between them, so without a solid lubricant to bond to the teeth faces, the constant near microscopic movement between faces causes them to wear away. This is termed "fretting wear".

 

Therefore, in this situation, what matters is the moly content, and quality. The grease is just holding the moly together, and keeping it in place for long enough for it to get burnished into the surface of the splines during initial operation after a new lube has been performed. Once that has taken place, the grease does very little (in fact, it is squeezed right out of the high pressure contact area). The moly is now burnished onto the spline teeth and stays there, providing a microscopic solid barrier against metal-to-metal contact.

 

True - however the grease has to be able to withstand the temp, friction, and RPM (slinging) to hold the moly in place long enough for it to be burnished into the surface.

 

BTW - I have heard others using that Krytox as well. I use Krytox 240 at work with space applications. It has the consistency of a heavy hand lotion. I personally dont like that stuff for any use. It seems to dry out and almost crystallize.

 

We have some MoS2 powder that I was considering using to make my own brew of moly grease. But after having the Honda stuff available at the place right up the street, I figured why reinvent the proverbial wheel grin.gif

 

now that we know what grease to use, what are the intervals for spline lubrication. i didn't see it as part of the normal service. thanks in advance.

john

Link to comment
now that we know what grease to use, what are the intervals for spline lubrication. i didn't see it as part of the normal service. thanks in advance.

john

 

That's not a new question, and I'll answer authoritatively only because I've read the answer 100 times. BMW doesn't prescribe any preventive maintenance for the splines. The closest it comes (from what I've heard) is lubricate the splines during normal service (e.g. when changing the clutch, transmission R&R, final drive R&R, & etc.).

 

Folks on this forum have been trying to identify the root cause of early spline failures on some R-bikes, and they've done everything from surveys to asking BMW, to trial and error engineering their own solutions (guess which approach worked best). If you go back 2-3 years and read up on "spline failures", you'll find a lot of enlightening info, but nothing that will tell you when to lubricate your splines. Opinions vary, with most indicating that every 30K to 50K miles it's not a bad idea to check the splines, and if dry or rusty, throw some 60% moly-lub on them.

 

A couple of the sharper guys on this forum have figured out that in at least some of the failed splines, the transmission case is misaligned with the engine housing (correct me if I'm wrong guys..), and the cause appears to be that the guide pin holes are misaligned. In that case, lubricating the splines might help, but you're probably headed for spline trouble no matter what service you perform. (In fact, though only a few reports have come in verifying misalignment diagnosed after a spline failure, I have yet to hear of anyone who had a spline failure, checked alignment, and found NO misalignment.)

 

The good news is, it appears that the misalignment causes spline failure relatively early in the life of a Beemer, so that if it hasn't happened by 30K or 40K miles, you're probably good to go. (However, most of us are going to lubricate splines on some regular interval no matter what, because we're one superstitious bunch of guys. NOT lubricating your splines will definitely mean that your drive splines will fail, even if lubrication has nothing to do with preventing it. grin.gif It's a proven fact ... lmao.gif )

 

I just R&R'd my transmission at 57K miles, and the drive splines look as though they just came out of a new parts box. No wear at all. (The transmission, on the other hand, was another story; I apparently got the Tustin, CA, police training bike. clap.gifdopeslap.gifclap.gif)

 

Anyhow, that's a half-a$$ed explanation. Others will quickly chime in to correct all my misstatements.

Link to comment
Don_Eilenberger
Agreed. But the actual "grease" in this application is not what provides any significant protection against fretting wear in the splines. It is the MoS2 that is doing the job, namely preventing metal to metal wear under extremely high contact pressure, between splines that barely move at all.
The carrier grease also provides protection against rust - which can also kill splines rapidly. Iron oxide from rust is abrasive - and that isn't something you want working itself into the splines. The ideal grease has a good carrier that has high temperature stability (so it doesn't do what BMW#10 did - which was melt and run off the splines) and an extreme pressure lubricant (the moly). Having a carrier grease that remains somewhat fluid also gives a source for refreshing the moly pressure-protective layer as it wears. Just dry moly won't do the job.

 

Paul Glaves mixes his own from Honda Moly60 and I believe Wurth 3000 last time we talked. This combines the extreme pressure capability of the moly with the cling and high-temperature characteristics of the Wurth grease.

 

At one point (quite a few years ago) Paul was more concerned about rust on the splines - and was using a boat-trailer wheel bearing grease, which was slightly acidic and would eat rust as it formed.

 

Dunno how much experience you have with splines - I do know on Paul's K75S (Ol'Smokey) - he had original clutch splines when it was totalled by an accident at 360k+ miles.

Link to comment

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...