Use of graphite or moly in diffs?

[Bigbjorn]

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?

[p38arover]

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

[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.

[Tank]

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.

[isuzurover]

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.

[JDNSW]

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

[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

[byron]

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!:(

[byron]

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.;)

[UncleHo]

G'day Brian Hjelm :)

I have used "Wynns Gear and Diff Additive" in both Gear/Transfer/Diffs. for years now, and used to use it in all my other cars as well, Holdens Toyo Crowns,BMC's, and V8 Fords (SV's) as insurance, and quietening;) works well n the Series Vehicles. I got into using it during the 60's at Castlereagh's 1/4 mile strip.:D


cheers

[Bigbjorn]

I have been aware for many years that Nulon does nothing except lighten your wallet as do most other oil additives. We always put moly or colloidal graphite in the diffs of our heavy trucks as the combination of excess loading, heat, & bad roads in a number of cases caused temporary distortion at the diff. head to banjo joint and thus major oil leaks. Treated diffs would tolerate low oil levels and even a few cases of water intake before we learned to fit elevated breathers to all road train units that did wet crossings. We also found that treated diffs had a longer service life between overhauls. I was wondering if it was worthwhile treating my LR's diffs even though they are not going to get anything like this sort of work.

[byron]

I have been aware for many years that Nulon does nothing except lighten your wallet as do most other oil additives. We always put moly or colloidal graphite in the diffs .......... Treated diffs would tolerate low oil levels and even a few cases of water intake ........... We also found that treated diffs had a longer service life between overhauls........... I was wondering if it was worthwhile treating my LR's diffs even though they are not going to get anything like this sort of work.

I think in the case of Moly. I'd be thinking/saying Yes, give it a go, it certainely won't harm, and it's cheap enough............as far as colloidal graphite I've read a lot about it that makes me say no, don't add it!

[shorty943]

For what it is worth, I am inclined to agree with Unca Ho. I've been using Wynn's products, in industrial engineering for years, can be a little pricey, but, you get what you pay for.
Saw a demo of Wynn's auto oil stabiliser years ago in the NT, that convinced me. 202 engine, sump doctored with Wynn's, then the sump was dropped and left off. Drove from Darwin to Alice for the annual show, drove around Alice and the showgrounds, all with no sump.
Just don't use a dry coloidal graphite, like most say, it makes ugly lumpy stuff and kills bearings dead. Pity about that Trumpy Trophy, sweatest bike ever built I reckon.

Shorty.

[lokka]

G'day Brian Hjelm :)

I have used "Wynns Gear and Diff Additive" in both Gear/Transfer/Diffs. for years now, and used to use it in all my other cars as well, Holdens Toyo Crowns,BMC's, and V8 Fords (SV's) as insurance, and quietening;) works well n the Series Vehicles. I got into using it during the 60's at Castlereagh's 1/4 mile strip.:D


cheers


Yep im with uncle ho on this one ive used wynns gearbox and diff treatment for years now and have never had a oil problem yet evcept for when i got oil in my rear diff and broke it due to a non functioning diff breather ...

Good reminder tho when im in super crap on friday to get me sum for the oil change in the lt95 ...

Cheers

Chris

[Tank]

For what it is worth, I am inclined to agree with Unca Ho. I've been using Wynn's products, in industrial engineering for years, can be a little pricey, but, you get what you pay for.
Saw a demo of Wynn's auto oil stabiliser years ago in the NT, that convinced me. 202 engine, sump doctored with Wynn's, then the sump was dropped and left off. Drove from Darwin to Alice for the annual show, drove around Alice and the showgrounds, all with no sump.
Just don't use a dry coloidal graphite, like most say, it makes ugly lumpy stuff and kills bearings dead. Pity about that Trumpy Trophy, sweatest bike ever built I reckon.

Shorty.
Great motorcycle the old Triumphs, had an ex-cops parade bike 69 Trophy, only had 400 miles on it, loved it, just wondering, how did they get that holden running without oil to pump up the Hydraulic lifters, I seen this Demo somewhere as well, I asked about the lifters, they told me to
Pi$$ off, always thought there was something not quiet right about that, Regards Frank.

[JohnE]

Aside from the new generation oils and advances in lubrication technology, I know an older 4wder who swears by molybond, I think its real name is molebdium disulphate.This bloke told me the germans developed it in the second world war.
Just a little bit here and a little bit there, is all you need.
Must be something in it as they are now moly coating projectiles( bullets for the uninformed) to slide down barrels without any drag.


john

[rick130]

I have been aware for many years that Nulon does nothing except lighten your wallet as do most other oil additives. We always put moly or colloidal graphite in the diffs of our heavy trucks as the combination of excess loading, heat, & bad roads in a number of cases caused temporary distortion at the diff. head to banjo joint and thus major oil leaks. Treated diffs would tolerate low oil levels and even a few cases of water intake before we learned to fit elevated breathers to all road train units that did wet crossings. We also found that treated diffs had a longer service life between overhauls. I was wondering if it was worthwhile treating my LR's diffs even though they are not going to get anything like this sort of work.

Brian, I used to talk regularly with a bloke that runs a fleet of trucks up and
down the eastern seaboard and his whole fleet was converted many years ago to full synthetic oil usage after working with both Castrol and Mobil in field testing lubricants. (he worked for Texaco in Europe in the late sixties)

He said that the final drive temps have dropped dramatically using Syntrax, (they actually got it approved by Eaton/Fuller after proving how much better results it was giving over the specced lubes) hub seals now tend to last the life of the vehicle and they no longer have to re-race Road Rangers every 400,000km, (Mobil SHC 30 or 50, from memory) although he did say that could be a combination of lubricant and better QC on Eatons part.
Here's a couple of Doug's posts on another message board.

my trucks are rated at 68500kgs (170700lbs) but we are legal at 42500kgs(93500lbs)and are always loaded at that (truely!). We do no empty running at all!
All of my trucks are OEM speed limited to 100kmh (62mph) and spend a lot of time between 80 and 100kmh. They run 1650rpm at 100kmh (4.33 diffs)

The DS462Ps are rated at 46000lbs and I use RTLO 18918B boxes (with oil coolers)

In my operation we have a few long & steep climbs but about 80% of the running is flat to mild undulating terrain

We found that running synthetic SAE50 (instead of mineral SAE50 or GL1 SAE90) preserved "new shift" feel to way beyond 1.3 million kms regardless of the Driver's skills - or lack of)
If a Driver is caught making clutchless shifts they are fired without arguement!

We change the transmission/diff oils every 1m kms or at four years! We replace gearbox filters at 150k kms and our clutches generally last for 800k kms (500k miles) on average

Our operating ambient temperatures range from -10C to 42F+ and this could be experienced on the same day!......


.......for many years I used Shell then Castrol's synthetic oils
We then tried Mobil 1 and the results have been identical

The gearbox synthetic is great at improving cold oil shifting

I still have a "soft spot" for Castrol's gear lubricants....

......In 1997 Rockwell ( then ) and Eaton ( then ) would not approve a synthetic GL5 75w-90 for use in their diffs. in Australia

I challenged their logic as it was already approved in NA at 38C> and had been since the early 1990s. Of course they could not explain their reasoning except to mention shock loading at high ambient temperatures. This was simply due to a lack of knowledge about their own Company's previous testing regime

We did our own ambient monitoring and found long distances - 800kms - at or below 2C overnight in mid winter ( up to +30C daytime )
We monitored the diff. temps and they rarely showed above 60C in these conditions
In the end and after producing the facts we obtained written approval from both Manufacturers

The change to 75w-90 also resulted in a 20C diff temperature reduction in mid summer days of 40C+

[Bigbjorn]

This is a normal medium service highway application with a six axle rig. I would expect the gear to last that long. This application is not to be compared with livestock road trains in Western Queensland on appalling roads/tracks and a gvm in excess of 100tons. We solved the problem of diff. oil leaks caused by housing distortion by machining an o-ring groove in the gasket face of the diff. head and eliminating the gasket with an o-ring which had enough resilience to cope with the distortion. I did the first one on our flat belt driven forty y.o. (then) Van Norman mill, which was replaced with a second hand ex tech. college 7 ton Stankoexport. Best milling machine I ever used. It could take a 1/2" cut in steel with an 8" slab mill with out a chatter.

[PhilipA]

Look, I do not want to get into a slanging match BUT.
I personally met a VC Commodore driven from Singapore to KL with no oil but treated with Nulon( publicity stunt for launch in Malaysia) when I was a Trade Commissioner. I have no relationship with Nulon.
To answer the question on lifters, they fitted solid ones.
The car had a radiator hose blow off while idling on the causeway, yet still made it to KL with no oil. It was a wreck when it got there , but get there it did.

With regard to teflon as a lubricant, I think many of you are confusing two different functions. I think the argument about "plating cylinders" etc is probably very overdone, and maybe there is no need in an engine.

However the function as a suspended solid lubricant in a metal on metal environment is quite different and there are numerous tests using test rigs that show that teflon is good in that usage.

I would use Molyslip if it were still available, but I think it has been discontinued. I went onto the relevant site and could find no mention.
I have also not seen it or a product like it for many years.

If someone knows where to get it please advise.
Regards Philip A

[rick130]

Aside from the new generation oils and advances in lubrication technology, I know an older 4wder who swears by molybond, I think its real name is molebdium disulphate.This bloke told me the germans developed it in the second world war.
Just a little bit here and a little bit there, is all you need.
Must be something in it as they are now moly coating projectiles( bullets for the uninformed) to slide down barrels without any drag.


john

molybond is just a % of molybdenum disulphide in a mineral oil carrier. There's no doubt MoS2 is brilliant in low speed, low temp situations when the main lubricants hydrodynamic film breaks down. It's ability to shear and plate metal parts, preventing galling and wear is well known, but if the lube already works fine under all operating conditions it's wasted, and in some situations can be deleterious, eg. in engine oil. A much better form of moly in engines is soluble moly, and these days it is being replaced with more exotic additives such as Boron.

Anyway, I always use a moly fortified (only needs to be 3-5% max) lithium complex NLGI 2 grease on any sliding coupling (splines) CV's, ball joints/tie rod ends, etc. Even uni joints. An old F100 I had still had the original king pins, tie rod ends, tail shaft spline and uni's with no discernable play on any item when I took it off the road after 500,000km using plain old Castrol LMM.

I just wouldn't bother adding it to any quality fully formulated lube. It may even be a component of the blend, (including antimony) although Boron and Calcium Carbonates are generally being used instead these days.

[JDNSW]

...... I think its real name is molebdium disulphate.....
john

Actually Molybdenum Disulphide, MoS2 is the active ingredient. Molybond has it in suspension in some kind of oil, probably with other additives as well.

John

[landrovermick]

i have been thinking of adding cleenfuels addetive on the next change - their fuel product and oil system cleaners are great

see here :

http://www.costeffective.com.au/

Mick

[MacMan]

Must be something in it as they are now moly coating projectiles( bullets for the uninformed) to slide down barrels without any drag.


FYI, use of moly on projectiles doesn't result in total loss of drag, and the main reason it is used is to reduce copper fouling in barrels. The fouling doesn't reduce life considerably during match use (most of the wear is in the barrel throat from the 50,000psi high temp explosions!) but it does reduce accuracy. There is a VERY small amount of copper vapourised by powder as it burns and this vapour is deposited inside the barrel. If there is enough relief in the bore surface it can gather enough to gaul and damage subsequent projectiles. When moly is used, it takes a number of firings to lay down a coating, but once established this coating prevents the gauling.

[landrovermick]

yeah our rounds at work are coated with black teflon type stuff for this reason - or at least i think thats what they tell us

Mick

[stevo]

I have used that shc50 mobil oil in my old series 2 landy what a difference that made,we had a fleet of 4wd trucks with snow ploughs and using 90/140 oil we would have to replace the bearings after the winter months were finished,switched to the synthetic oil the transfer cases did not need touching again just changed the oil every year.

[shaunp]

Never put graphite in any thing that has roller, ball, timken bearings. These beargings need to roll not slide, graphite makes them slide and flat spotts them. Same reason you use different grease in wheel bearing/unis to ball joints, one slides one rolls. I run Castrol SAF-XA synth in all diffs

[JohnE]

Macman, sounds like your a benchrest guy, i have read all the articles about moly coating and the subsequent bedding in procedures. Too much mucking about for me. i used it as a simplified description for the other uses of moly.

Mick, the SXT rounds, have a sort of wash, like a dark copper, on them, its not a moly coating.( check the packets at your next shoot) Instructors know all, are the gurus and when they don't know an answer they make it up.
the practice ammo has that coating on it to stop the barrels leading up, there was the green slime ,the black slime and the clear slime, don't know when you did you conversion course, but the first few I ran in the early days of glock conversions, you could peel the lead out of the barrels at the end of the course.( but that was in the days of the 900 rd conversions,)
That became a problem because the armourer at a well known facility west of sydney split some glock barrels , allegedly because of the leading( i saw a couple they were split/cracked under the breach) but thats another story.
Because the tolerances are so tight, the slime was added to the lead as a coating but it isn;t moly.


john

[Larns]

If the grease that is installed in the front CV housing is good enough for the extream pressures that the CV's undergo then surely this could theoreticaly be used in diffs..............this would solve the problem of leaking diff pinion seals, and cross contamination from the CV housings into the diffs.............hate doing axle seals, such a time consuming job for such a simple quick replacement.

Cheers

[JDNSW]

If the grease that is installed in the front CV housing is good enough for the extream pressures that the CV's undergo then surely this could theoreticaly be used in diffs..............this would solve the problem of leaking diff pinion seals, and cross contamination from the CV housings into the diffs.............hate doing axle seals, such a time consuming job for such a simple quick replacement.

Cheers

Problem is, that while diffs have sliding contact on the teeth, they also have roller bearings. See the various posts above - MoS2 seems to be OK in diffs but not graphite.
However, you need to have a liquid lubricant in the diff as if you just had grease it would soon (as in a few revolutions) get squeezed completely off the teeth, and would not run back on like the oil does. Also, the liquid helps helps to cool any hot spots. The CV joints can live with grease as most of the time there is very little movement on the joint itself - and it can be made into a grease tight container itself as with open drive axles. Where it is in an oil filled ball swivel as in most Landrovers, the lubricant has to be at least semi-liquid.

John

[Larns]

john
The grease that goes into the LR swivel housings (that you get off LR) is a very liquid type, you can actually drain it out of the drain plug (abait it takes longer that gear oil). An the one shot satchet that you can get off LR dosn't fill the swivel housing, in fact it dosn't even come close to the bottom of the fill plug.
I'm awear that very few people actually use the LR stuff so I do see your point of view. If they were to "make" it as alot of people do, and it was too thick it would be no good for diffs at all.

How about this angle then, as I do use the grease from LR. As it stands now, I have grease from my swivel housings leaking into my diff housing. Will the added moly in the diff oil be detrimantal to my diff center and bearings, from reading the above posts I would assume not?

Any other thoughts?

Cheers

[Blknight.aus]

I swear by moly in landrovers and just about every thing else thats not going to be exposed to freezing conditions or salt water on a regular basis.

I avoid intentionally using it inside of engines but dont get upset if some gets in there.

Ive been doing it for years and as of about 3 years ago the ADF has switched the swivel hub lube to a special moly based grease.

so good enough for them, good enough for me...

Just dont go adding too much to diffs or tcase's it should still flow otherwise your going to have overheating problems due to poor heat transferance through the "oil".

[byron]

I personally met a VC Commodore driven from Singapore to KL with no oil but treated with Nulon( publicity stunt for launch in Malaysia) when I was a Trade Commissioner. I have no relationship with Nulon.
To answer the question on lifters, they fitted solid ones.
The car had a radiator hose blow off while idling on the causeway, yet still made it to KL with no oil. It was a wreck when it got there , but get there it did.

that show that teflon is good in that usage.



The website that debunked Teflon I referred to earlier also shed some interesting light on this "old one"......

.......Nulon did the same with a Commodore driving from Sydney to Melb. sometime in the 80's.......lots of publicity and boy!, did they flog that in their advertising........not these days though, ever wonder why on earth not?:o .......

......Coz in the U.S. Briggs and Stratton Co. did a public demo wherein they took one of their engines, new, ran it in as normal, then drained the oil out and then ran it for "x" number of hours or even days.......it ran OK........was totally f****d at the end of it, but it did run the distance.;)

[PhilipA]

I did some research yesterday to see if there were any recent unbiassed tests.
I didn't find much but I did find that Du Pont now sells a line of greases an lubricants containing Teflon.
www.dupont.com/lubricants/en/literature/pdf_files/H-79785-1.pdf (http://www.dupont.com/lubricants/en/literature/pdf_files/H-79785-1.pdf) .

They also now do greases for bicycles which to me would imply that in this case teflon is OK in roller bearings.
http://www.sandsmachine.com/pace.html

Now Du Pont at one stage came out with a statement that Teflon was not effective in engines, but seeing they sell a grease, and talk about anti scuffing etc etc one would have to assume that they see benefits in Teflon in gear lubrication.

Even though Byron selectively quoted me ( not a politician are you?) , my point was and is that even though Teflon might not be useful in engines it is OK in transmissions.
Seeing no one has come back with a source for Molyslip or similar, I will keep using my Teflon.
Regards Philip A

[shaunp]

The best oil for diffs is synth, why 2 reasons, 1st because if you get water in it will cook out as long as you keep driving and keep the diffs hot, second because synth is simply a better oil in most cases and gives better protection. I say in most cases because this is not the case in a flat tappet engine where you need zinc in the oil to make the cam live. Most modern engine oils lack zinc compounds to protect the cat convertors.