Moly and wheel bearings. Yes I've searched

[Zukinut]

Ok, I've spent the last 2 days (about 10 total hours) researching grease for a Toyota truck 4wd front axle application. I've read some very good posts with some very good points but a true answer is never given. Maybe this thread will provide all the future searchers an answer, so here goes.

I'm rebuilding te front end in my 95 land cruiser. The factory specs a lithium based moly added grease. There are several options for this. Problem is Toyota specs a high temp wheel beating grease non moly for the bearings. Inside the knuckle it is absolutely impossible to keep the two grease separate. The knuckle geese will ALWAYS end up in the trunion bearings and vice versa. And in hot temps the liquified knuckle grease will travel down the spindle an mix with the wheel bearing grease, and vice versa.

In my non full time 4wds I usually just use high temp wheel bearig grease throughout, it doesn't get used enough to hurt the axles. In this and other full time Toyotas, having the moly is a bigger deal.

I say all this in an attempt to spare us all some time in the long run.

So can a 3% lithium moly such as cats moly3 or a 5% calcium sulfonate moly be used in the trunion and wheel bearings on a heavy 4wd vehicle. If yes, awesome. If not, then I'll just use high temp throughout and take it all apart and repack everything more often.

I apologize for the long post, but I wanted to try to cover most bases in the first post.

Thanks very much for your time.
Will

 

[Trav]

I would use this.. Great stuff!

http://www.redlineoil.com/product.aspx?pid=82

 

[Chris142]

i would pack all the bearings with the same grease and not stress over it.

 

[Tegger]

Originally Posted By: Zukinut
The factory specs a lithium based moly added grease.

That's for the inside of the knuckle, where the CV joint and "trunion" is. What's inside the knuckle is NOT a trunnion, but is a set of tapered roller bearings similar to those inside the brake disc hub.

The grease will mix between knuckle and CV joint, but that's OK, since both take the same grease.

Originally Posted By: Zukinut
Toyota specs a high temp wheel beating grease non moly for the bearings.

That's for the OTHER tapered roller bearings, the ones inside the brake disc hub. Those are quite totally sealed from the knuckle parts.

 

[Zukinut]

I mean no disrespect but the 2 are not totally sealed from each other. Birfield,knuckle,trunion (kingpin style tapered roller bearing, Toyota just happens to call it a trunion) grease will mix, it's all sealed in the same housing and will most certainly travel down the spindle and into the wheel bearing hub. I'm sitting here looking at what happens when 2 different greases are used. The previous owner used two different styles and it made a mess, and that's why I'm having to do this in the first place.

Trav, I can't get it locally and this is a project that has to be completed this weeked. I can go back in at a later date if I must, but this go round has to happen this weekend.

 

[Trav]

I would go with the Valvoline SynPower and call it a day. It seems to meet all the requirements.

http://www.valvoline.com/pdf/synpower_grease.pdf

http://shop.advanceautoparts.com/p/valvo...vv986/7070009-P

 

[Zukinut]

Trav, sounds good.

Why are some people against moly in wheel bearings. Is it to slippery or to thick for some or ?

Not questioning anyone, just trying to learn as much as possible.

Thanks again
Will

 

[Rand]

Originally Posted By: Zukinut
Trav, sounds good.

Why are some people against moly in wheel bearings. Is it to slippery or to thick for some or ?

Not questioning anyone, just trying to learn as much as possible.

Thanks again
Will


google and in 2.5 seconds found this nugget of wisdom

Greases containing moly are recommended for roller bearings subjected to very heavy loads and shock loading, especially in slow or oscillating motion such as found in universal joints and CV joints. If such greases are used in high-speed bearings, problems can be experienced with roller “skidding” where the bearing roller fails to rotate through the full 360 degrees due to reduced friction. As a result, the roller develops flat spots, and its service life is reduced.

 

[Trav]

As Rand posted it can cause skidding in higher amounts like 5% and up. 3% doesn't appear to cause any problems and most greases in this range like the Valvoline state it can be used in wheel bearings.

Ideally you would want a 5% moly grease in the CV and 3% or none in the wheel bearing but this is not an ideal application. IMHO the slightly lower moly content is a good compromise all round.
Using it in all parts also prevents cross contamination of base stocks, i would feel good about using it.

 

[AMC]

I use and recommend Valvoline synpower as well, especially for what you are asking here.

If you want a good general purpose, high temp, disc brake wheel bearing rated lithium complex grease without the moly, use Mystic JT6.

If you want the same as above but with more of a waterproof or marine flavor to it, Use Green Grease or Lucas marine grease. Both are lithium complex, high temperature, and very washout resistant. Green grease is especially sticky, stringy, tacky, plasticy and god awful to wash off your hands. It works great for harsh 4wd/off road applications.

 

[Zukinut]

Thank y'all very very much. This thing will never see more than basic fire roads and snow. Washout isn't a major concern.


One last question and I'll stop bugging y'all, can lithium bases and calcium sulfonate bases be mixed. If so I can get away with the 5% and 3% as suggested above. Synpower is available at advance so it's a closer drive than cat.


Thanks again very much.

Will

 

[Tegger]

Originally Posted By: Zukinut
I mean no disrespect but the 2 are not totally sealed from each other. Birfield,knuckle,trunion (kingpin style tapered roller bearing, Toyota just happens to call it a trunion) grease will mix, it's all sealed in the same housing and will most certainly travel down the spindle and into the wheel bearing hub.

I'm looking at the factory diagrams and instructions (which are VERY detailed and full of images), and I cannot see how it could possibly happen that the hub grease could ever mix with the wheel-bearing grease -- unless somebody left out a gasket or two.

You may be missing parts from your assembly.

And the word "trunnion" appears nowhere in the factory documents. Toyota is calling that part a "knuckle arm".

If you like, I can email you the three documents I have. Just PM me with an email address.

 

[Kestas]

Wheel bearings aren't considered high speed bearings. Moly fortified grease should be fine for wheel bearings and won't promote skidding, but isn't absolutely necessary. What is necessary is some type of EP additive.

I've seen lots of skidded bearings. None have been attributed to the lube being "too slippery." Skidding typically occurs only in high speed bearings when there is a combination of too much clearance and not enough lube.

 

[Zukinut]

Tegger,

Not trying to start an argument. The bearing is between the knuckle and arm. It's just like a closed knuckle with brass bushing. I have all the books as well, and I agree it shouldn't happen following the pictures but I promise it can.ba we know sometimes books dont equal real life. It comes down the spindle chamber. It doesn't happen often, or a lot, but when it does it makes a mess.

Plus why have 2 grease guns, bearing packers, etc, lol


Thanks again for all the help it's greatly appreciated.
Will

 

[Zukinut]

Tegger, while disassembling the other side I studied everything. When it's all buttoned up there is about 1/2" of axle shaft exposed past the spindle between spindle and drive flange. Thats how the two greases combine. Please don't take me as a smart alek or a know it all as I'm in no way trying to do so. Just trying to explain how the two greases can combine.

Thanks again
Will

 

[wokeupdead]

If i remember correctly, I used Moly CV grease in the birfield joints. The trunnion bearings(kingpin) should be ok with this same grease. Very slow motion, just steering pivots like ball joints. The wheel bearings use regular wheel bearing grease. Make sure you knuckle ball seals are good.

The only time I saw a big mess in the knuckle end of those axles is when the outer axle seal "failed" and differential oil filled and mixed with the CV grease for the birfield joints. Often the seal surface of the axle shaft was grooved, and would leak even with a fresh seal. So also inspect axle shaft where differential seal rides.

 

[cb_13]

Ford recommends their black Motorcraft grease in wheel bearings and for chasis lube. It contains moly. I used it for absolutely everything during the 10 years I worked at a dealership.

 

[artificialist]

I just use Valvoline Durablend everywhere, and I never have a problem.

 

[willbur]

So moly is OK for wheel bearings now? Lots of discussion here indicated it was harmful for wheel bearings. That it was abrasive and ment for sliding surfacess only, or that it was too slippery. So...which is it?

 

[SargeBB]

Here is my rationale: Many (including me) won't use Moly grease in wheel bearings. While it is true, Ford/Motorcraft recommends 3% Moly, some of us have learned the hard way. My stock 1993 SWB Ford 300 six 4x4 had steep driveshaft angles. All 4 u-joints were replaced under warranty. The needles were pulverized. The Ford mechanic properly packed them with the Motorcraft moly grease...I know; I watched him do it. Before the little 1/2 ton had 60,000 miles, I had to replace the joints, this time I did the work myself, using Spicers with zerks, packing them with Chevron Delo #2, non-moly. When I sold the pickup, those Spicers had over 100,000 miles on them and were in great shape. Bottom line: Folks like me say, "Don't use grease containing any moly in wheel bearings or universals." Some tell you moly is okay in such applications. Few experienced people, including most who use the moly will tell you that you 'must' use moly grease in w.b.'s & u-joints.