Stupid grease question

[natvet]

I am in the middle of mini truck disc swap.(Thank God for 73Guppie's write up). Had a quick stupid grease question. I bought good quality bearing grease. Can I pack the knuckle with this or should I get Moly grease? I see that 73Guppie used 2 different types in his write up. Thanks guys
Nathan

[lostmarbles]

I'd use the moly grease Nathan.

[orvis17]

Please explain to me why the Moly would be superior to a high quality grease...

[lostmarbles]

Originally Posted by orvis17

Please explain to me why the Moly would be superior to a high quality grease...

Damn. I was hoping to avoid that Nathan.......

It's just that I've always used moly grease in that area and it is specifically recommended for CVs whereas the ordinary grease used in most bearing applications (and universal joints etc) is not.

I think it has better "stickability" and still provides some lubricating qualities when it has "dried out a bit" (by the oil being thrown out of it by centrifugal force). When you think about - A big CV joint spinning around would have a high tendency to fling out oil. (And oil does tend to separate out from all greases.)

Sorry - Not a very technical answer.

I always use moly grease on balljoints too. Now I wonder why I do that? ....................I guess it is the "still able to lubricate when it has dried out" characteristic. And the grease there tends to ooze out its oil a bit too.

Lots of what I do now has become "pure habit" after owning my cruiser for 27 years. - But I really don't think "wheel bearing grease" is ideal for your knuckles no matter how good quality it is. (On the other hand - if you were to use it there - I wouldn't expect you'd to be able to notice any wear problems occurring -------for a very long time anyway.)

So I guess I'm saying stick with moly for your knuckles because there is NO DOUBT that it is designed specifically for that sort of application.

PS.... I must have got it right anyway - Cos at 240,000km I'm still on original balljoints and I've never had to replace or adjust anything in the knuckle area.

[natvet]

Lostmarbles...... Thank you very much for your time and opinion. I am off to the store for some moly grease to pack'em with.

Nathan

[andrewfarmer]

Originally Posted by orvis17

Please explain to me why the Moly would be superior to a high quality grease...

Basically because it slides better.

w/b grease is a carrier for the oil that lubricates the 'turning' bits - plus wont melt at hi temp.

Moly grease slides and is good for things that slide but dont turn, like tres, birfs, etc

That's the theory I work on anyway

YMMV!

[theo]

Originally Posted by andrewfarmer

Basically because it slides better.

w/b grease is a carrier for the oil that lubricates the 'turning' bits - plus wont melt at hi temp.

Moly grease slides and is good for things that slide but dont turn, like tres, birfs, etc

That's the theory I work on anyway

YMMV!

That's how I see it too.

From the little reading I've done on grease formulations, molybdenum disulfide forms a thin, solid coating on metal surfaces that protects better in cases of high pressure or shock loads, like what a steering knuckle sees.

I read one account of some antique auto owners who used it on close tolerance mainshaft bearings. Their bearings burned up and they figure that thin coating was just enough to make the clearances too tight.

I would stick to wheel bearing grease on the wheel bearings and moly in the knuckle.

[mustardfj40]

I've just installed a set of chromoly longfields, and the longfields came pre-packed with grease which is thick and looks like wheel bearing grease to me...But I kept the moly grease in the knucles.

[crushr]

FSM specifies moly grease for CV Joint and knuckle. As does every CV joint vehicle I've ever owned or worked on.

In BOLD letters on pages 6-9 and 6-10 of the 1980 FSM, detailing assembly of CV (Birfield) joint: "Coat with molybdenum disulphide lithuium base grease before installing"

On page 6-16 of same manual, detailing final assembly of knuckle: "Pack molybdenum disulphide lithium based grease into the knuckle to about three fourths of the knuckle volume."

Good enough for me.

BTW - mixing types of grease (e.g. different for birf v. knuckle) is likely a very bad idea unless you know they are compatible. Incompatible greases can cause lubricant matrix breakdown, resulting in a watery mess and component failure.

[orvis17]

Thank you...our family runs some ag equipment and I am trying to convince the father-in-law that it is worth the extra money, but he thinks because of the tackiness that it will attract and hold contaminants more readily...what do you all think?

[John Smith]

Originally Posted by orvis17

Thank you...our family runs some ag equipment and I am trying to convince the father-in-law that it is worth the extra money, but he thinks because of the tackiness that it will attract and hold contaminants more readily...what do you all think?

Use what the factory manual calls for. To save a few cents on grease your FIL would rather risk a much more expensive repair?

[orvis17]

its actually quite a bit more than a few cents...the grease consumption is amazing...some of the apparatus call for grease after every 10 hours of use...it adds up quickly, and of course there is the quantity...

[John Smith]

Originally Posted by orvis17

its actually quite a bit more than a few cents...the grease consumption is amazing...some of the apparatus call for grease after every 10 hours of use...it adds up quickly, and of course there is the quantity...

If I made the investment in big $ equipment I would use what the manufacturer called for. They specify a particular lubricant for a reason. I wish your FIL the best of luck with his experiment.