U joint grease

[Cruiserdrew]

Yep, lithium soap is what thickens oil into grease. Lithium is a soft metal. Grease liquifies (drops) at about 180C, the melting temp of lithium. I use Mr Moly grease, it's thickened with clay, giving it a crazy high drop temp.

It is a good point about the soap clogging zerks, I wonder if my clay thickener might leave my zerks plugged worse?

Hang on here Scott. The melting point of Lithium metal (356F=180C) has nothing to do with the discussion here. There is no Lithium in it's metallic form anywhere near the tubes of grease available everywhere.(If there were, it would be a very bad thing!) It's Lithium soap where Lithium is the cation and in it's ionic form. Any soap probably does have a lower melt point than clay, but that is not really relevant to this discussion. Toyota calls for a Lithium based grease. You should use that. Most "moly" greases are lithium greased with moly added as a wear agent. Most, but not all, moly greases are rated for wheelbearing use (Like Amsoil, Valvoline durablend, Valvoline "Ford") etc. Using any of them will be fine in this application.

Also, remember this. Most people NEVER grease their zerks. Sad but true, so some grease is better than none. U=joints are not a high temp application. Any grease will work. Wheel bearings are a high temp application, but only because of the heat generated by the disc brakes.

I like the old quote from the 80s list--"where grease is, water is not", so grease is your friend. I don't think what grease actually goes in the u-joints matters much at all. If it says grease on the outside of the tube, it will probably work.

 

[Tools R Us]

...
Also, remember this. Most people NEVER grease their zerks. Sad but true, some some grease is better than none. U=joints are not a high temp application. Any grease will work. Wheel bearings are a high temp application, but only because of the heat generated by the disc brakes.

I like the old quote from the 80s list--"where grease is, water is not", so grease is your friend. I don't think what grease actually goes in the u-joints matters much at all. If it says grease on the outside of the tube, it will probably work.

Exactly, if I had to guess u-joint bearings turn at less than 100 rpm, glacial speed in the bearing world. I have changed tons of them, the vast majority were lubrication related, as no lube, don't ever remember never seeing one with evidence of incorrect lube failure.

On most, when a cap is removed, rust dust falls out. Rust doesn't easily form in the presence of oil, so the lube went away and it continued to operate long enough to rust. This wouldn't happen with a higher speed bearing, even a wheel bearing (what ~500 rpm) would heat and weld it's self together when oil starved.

Grease zerks can be removed and cleaned, brake, carb cleaner works well. If the bore inside the joint is gummed, plugged your best bet is to take the joint apart and clean.

 

[Tools R Us]

Doing grinders today so popped a seal and shot a pic, not ‘80 related, but may give some idea of lube need.

This is a typical R12 bearing, it’s the lower spindle bearing in a 4 hp air grinder that spins a 6x3” 7lb stone/backing plate at 6000 rpm, two shifts a day or ~10 hours a day run time. Between the ball is a blob of grease, there are 4 around the inner race, that's it. This bearing takes a huge beating, will run about 1 year before needing replacement. It will fail from debris, if we could keep the debris out it would run several times that long with only that much grease.

 

[scottm]

Between the ball is a blob of grease, there are 4 around the inner race, that's it.

That seems like less than the 15-20% mentioned by Tools, kinda surprising.

 

[Tools R Us]

That seems like less than the 15-20% mentioned by Tools, kinda surprising.

Bearings have several specs, precision, seals, etc. When specifying a bearing for rpm, one of the biggest changes is grease loading, higher rpm = less grease. This bearing is used in several applications, some spin 24K+, so if I had to guess it's spec is ~25-30K rpm.

When I started doing these tools the bearing was an issue, they would fail in a couple of months. We changed bearing spec a couple of times, made several types of dust seals/shields, etc, now they are lasting about as long as other components, so the bearing is no longer an issue.

 

[veeLC]

I used to work on helicopters and they would always use the red stuff. Must be good after all theres no where to pull over up there. WalMart has it cheap next to the moly stuff.
aloha

 

[jonheld]

FWIW I have heard the same things about moly grease causing sliding. I spoke to an Amsoil engineer about that and he said it is possible, but not likely to happen in the real application.

I've been using Amsoil moly grease in birfs, wheel bearings, uni joints, pretty much any application that requires any kind of grease, for the last 8 or so years and it works pretty well. I'm still on my original front drive shaft from 1991 with the original bearings and zero slop so I can't complain all that much. Just shy of 200K miles on a set of bearings doesn't suck.

The original poster has mentioned several times how "critical" universal joints are, and I agree, but they are also replaceable parts. Nothing lasts forever. Don't stress too much over something that doesn't warrant it. Use any quality grease regularly and you will be fine.

 

[scottm]

The original poster has mentioned several times how "critical" universal joints are, and I agree, but they are also replaceable parts. Nothing lasts forever. Don't stress too much over something that doesn't warrant it. Use any quality grease regularly and you will be fine.

Yeah, come to think of it, I replaced all the bearings when I did my front seals, it wasn't that much of an added expense. So I'd probably be ok with moly grease. Still, it wasn't an extra effort to use general purpose grease in the wheel bearings.

 

[Cruiserdrew]

It's funny, and driveshafts aside, but I use Moly grease in the birf and knuckle and Mobil1 in the wheel bearings. Not really sure why, I've just done it like that for 10 years and don't really think about it. Amsoil moly grease lives in my grease gun and that what goes in the u-joints.

 

[MoGas]

My U-joint gun is loaded with Valvoline Cerulean #2.

 

[landcruiser3DP]

so was there a consensus here on a single product for yokes and ujoints? i was kind of hoping to keep it to one gun and i see there are multiple experts assembled here. THANKS.
edit: oops. looks like Amsoil GPTR2 might work?

 

[Bambusiero]

As a reminder to anyone here who has not heard of this - be careful not to over grease the zerks that feed the sliding spline on the drive shaft. Doing that can hydraulically "jack up" the drive shaft (which you can actually watch happen), preventing it from be able to shorten as you go over bumps. That will put LOTS of stress on everything.
You can unscrew the zerk and let any excess grease squirt out - might need to get the spline to slide / shorten a bit to force out the excess.
I have done this as a "once in a great while" - super spline greasing service. otherwise - just a couple of squirts to freshen up.
All of this is not a concern for the U-joints - just watch for some fresh colored grease to ooze out the seals - wipe up - done.

Personally, I've been using Green Grease for the drive shaft for a long time now.
Not that that proves anything. It just seems to me - fine for this application, plenty sticky, stays in place just fine, rated "EP" extreme pressure.
And...the main thing... I absolutely HATE GREASE GUNS - one in my shop is enough - refuse to screw around with others for some vague "betterness".

 

[Tachycardic]

I keep Valvoline Palladium in my grease gun.

If the needle bearings don’t like it, they haven’t told me about it.

 

[Bambusiero]

I like Valvoline Palladium too, but don't keep it in a grease gun. It stays in the original tube until spooned out for whatever purpose. I decided to use it for front wheel bearings as well as the Birfs. It's rated for wheel bearings, and I just don't care about all that worry and hand wringing about molly in "high speed bearings", which wheel bearings are not, anyway. Aside from the dark gray color (which gets on everything), it has a nice soft buttery consistency, and has never oozed or separated on me (have some red wheel bearing grease that does that - yucky mess dripping around).

So - 2 greases for me:
- Green Grease in the gun for drive shaft only.
- Palladium in the tube for Wheel bearings & Birf)
That's it - everything is covered.