Thread: Use of graphite or moly in diffs?

I remember it being the thing many years ago. I may still have one of the moly sachets out in the garage. Dunno if it worked.

I'm pretty sure it was called MolyBond.

Ron

why bother ?
just use a premium gear fluid and don't think anymore about it. The state of play in lubrication these days is so far ahead of even 10 years ago it's staggering, but if you really wanted to add something, I'd use MOS2 over graphite any day.
Texaco/Caltex used to use a lot of soluble moly (the only type of moly that should be used in engine oil) but use a very trick borate ester base in their premium gear oils these days.

Me, I just use Castrol SAF-XA (80W-140) and Syntrax (75W-90) PAO/ester based synthetics as I can get them easily and are top shelf lubes.

Originally Posted by Brian Hjelm

Anyone had any experiences of adding graphite powder, colloidal graphite or molybdenum disulphide products to LR diffs, not to quieten, but as a lubrication enhancer and insurance policy?

NEVER add Graphite Powder to any mechaincal device that has BALL or ROLLER bearings, the graphite will build up on the balls and rollers and the races and cause siezing. Years ago some used to add graphite powder to engines with worn slipper bearings, a mate of mine thought he would cure the crook Ball and Roller bearings in his 650 Triumph Trophy, he got less than 200 metres before it through him off, with a totaly stuffed siezed engine, Regards Frank.

Originally Posted by rick130

why bother ?
just use a premium gear fluid and don't think anymore about it. The state of play in lubrication these days is so far ahead of even 10 years ago it's staggering, but if you really wanted to add something, I'd use MOS2 over graphite any day.
Texaco/Caltex used to use a lot of soluble moly (the only type of moly that should be used in engine oil) but use a very trick borate ester base in their premium gear oils these days.

Me, I just use Castrol SAF-XA (80W-140) and Syntrax (75W-90) PAO/ester based synthetics as I can get them easily and are top shelf lubes.

What Rick said - modern oils are a long way ahead of any of the old-tech additives. When tolerances were huge and lubricting oil was something you squeezed out of a whale, the the additives may have had a benefit...

I once worked with some lubricant R&D chemists/engineers - they always used to laugh at end-user-added additives.

Solid additives such as graphite or MoS2 are only useful in the event of the liquid lubricant failing - in the case of a diff this would be when you lost all the oil. And in that case, the lubrication would be inadequate for it to last long, and the solid lubricant provides no cooling. Remember that the sliding tooth contact in spiral cut gears requires an extreme pressure lubricant - and the tooth contact needs cooling.

As Tank comments, graphite is not indicated for roller bearings, and I don't think MoS2 is much more desirable - both have their place only where you have sliding contact, and particularly where you can't be sure the liquid phase will stay on the surfaces. I have seen MoS2 used in gearboxes, without either apparent benefit or harm, can't remember seeing it used in diffs though.

John

What about the modern version, teflon.
I use Nulon in my BW transfer case as AFAIK its good for chains. Considering the cost of a new chain any help is accepted.
I believe it is also beneficial in diffs. I have had it in for extended periods (years)with no obvious ill effects, and hopefully some good effect.
Regards Philip A

Originally Posted by PhilipA

What about the modern version, teflon.
I use Nulon in my BW transfer case as AFAIK its good for chains. Considering the cost of a new chain any help is accepted.
I believe it is also beneficial in diffs. I have had it in for extended periods (years)with no obvious ill effects, and hopefully some good effect.
Regards Philip A

I USED to be a great believer in the Nulon Teflon range of products, using them for years [nearly 10 ?].....I was even convinced that it had allowed me to drive a V6 Volvo from Byron Bay to Sydney with a blown head gasket leading to no coolant leading to temp guage off the end of scale and resultant no oil pressure [i.e. 800klms @avg 100 kph !!!!!].....even with all that the car drove around for nearly another year, just locally - using about 2 L of water per 5-10 klms!

However I chanced upon a website that so fully debunked, in a very sound scientific way any possibility that Teflon could or does work as claimed. In fact, even Du Pont Corp [maker of Teflon] has sued and won an injunction against makers of these products [NOT Nulon, but others in U.S.] from using the brand Teflon in any advertising or labelling etc, on the basis that Teflon does not and cannot work or be used in ways like these guys claimed, they now buy the stuff as a generic which is mage in India.

A great pity as I said.......I haven't got the relevant URL's at the moment......but Google it - it's a real eye opener!........as I said, I was shattered!

Originally Posted by Brian Hjelm

Anyone had any experiences of adding graphite powder, colloidal graphite or molybdenum disulphide products to LR diffs, not to quieten, but as a lubrication enhancer and insurance policy?

I put in a slurry of about 2 cups of Molybdenum disulphide Grease and 90 EP to "top up" my transfer case in my Disco 1 3.9 and FINALLY got a smooth and easy lock-unlock function!!! [Hi to Lo and back had always been OK, but lock-unlock and back was always a fiddle]

I've been using a 50/50 slurry mix in the spheres of all my LR's for years now also.