Overthinking things again - Grease - Wheel bearings

[TechnoWeenie]

As usual, I tend to overthink things...

Realistically, in my opinion, with modern greases, any grease I choose should be better than what was around when the deuce was manufactured, but that's not always the case....

So, I'm looking at bearing grease.... and the options are endless..

Lithium, with moly, no moly, low moly, high moly, urea based, synthetic, and on and on and on....

I've searched everywhere, including other sites and even youtube and everyone has their own opinion, or just says 'it doesn't matter, just make sure you use the correct type of grease'.....

It would seem to me, that a high temp synthetic grease would be the way to go.... would it not? Are there compatibility issues like with the GO and not being safe for use with older metals? What about mixing grease? If I'm topping off grease do I have to worry about mixing the old and new and them not being compatible? Are there any issues running 'high temp grease' in applications that would normally call for a lower temp grease?

I was looking pretty hard atLucas Red n Tacky, but then also saw Mystik JT6 that seemed almost identical in spec..... but then fell down the rabbit hole...

Any insight?

 

[royalflush55]

It is not a good idea to mix different types of grease.
It is not a good idea to clean bearings with gasoline.
Use a good cleaning solvent instead, Then let dry completely.
Do not use compressed air and spin a bearing to dry it. This is very dangerous as the bearing can come apart very quickly!
I have used Mystik High temp grease and Lucas Red and Tacky in all my wheel bearings on the farm with good results.
They are both acceptable. Both stay put in a packed wheel bearing like intended and do not "melt out".

 

[bprzyw]

Lucas Red n Tacky all the way!!! Works on everything!

 

[Gypsyman]

I went with the red Mystic JT-6 (bucket and tubes) from Napa. It's a #2 bearing and chassis grease. I look at it the same way. Lubricants have come a long way since these trucks were produced and the LO was written.

 

[G744]

Just no moly grease. If it mixes with a small leak of gear oil, it will turn to a paste with little lube properties.

Seen it happen.

DG

 

[V8srfun]

This subject is full of opinions and they all have validity but that does not make any of them right or wrong. I personally use car quest wheel bearing grease I can get the part numbers if you want them but it is not as thick as many of the red tacky greases out there. My theory is that the thinner wheel bearing grease will flow better and help keep fresh grease in the bearing. I have been inside many hubs with the super thick stuff and it does not move from where you put it. I am hoping that the thinner grease that I am using will work and flow in through the bearing keeping it better lubricated.

the super thick greases will not flow on its own if you have a 5 gallon bucket of it and move it all the way over to one side it will stay there. Where the car quest stuff will level back out. My thought is that that will be the case in my hubs as well and the grease will push back in to the bearings while at rest. I will be able to prove or disprove this theory when my truck is apart again. If the grease has been circulating I will be able to see it.

 

[Mullaney]

This subject is full of opinions and they all have validity but that does not make any of them right or wrong. I personally use car quest wheel bearing grease I can get the part numbers if you want them but it is not as thick as many of the red tacky greases out there. My theory is that the thinner wheel bearing grease will flow better and help keep fresh grease in the bearing. I have been inside many hubs with the super thick stuff and it does not move from where you put it. I am hoping that the thinner grease that I am using will work and flow in through the bearing keeping it better lubricated.

the super thick greases will not flow on its own if you have a 5 gallon bucket of it and move it all the way over to one side it will stay there. Where the car quest stuff will level back out. My thought is that that will be the case in my hubs as well and the grease will push back in to the bearings while at rest. I will be able to prove or disprove this theory when my truck is apart again. If the grease has been circulating I will be able to see it.

.
I remember that forever we used Chrome Moly for wheel bearings. There may well be better stuff out there, but of all the things we had go wrong - wheel bearings "going dry" wasn't a problem.

The exception for trucks that were in swamps for months at the time... Even then it wasn't because of a bearing or grease failure. Just that swamp water had a tendency to have tanic acids in it that ate metal over time... (specific mention of purging of contaminants)

I discovered a posting from an industrial Lubrication guy and his "take" on grease is posted below.


Jack Koenig, Industrial Lubrication Field Application Engineer
Molybdenum disulfide (Moly) is a solid additive, most commonly used in extreme pressure applications. The Moly particles are intended to fill in tiny imperfections in the machined surfaces and protect against “welding” during shock loading and heavy loads; however, the material is also known to stick to surfaces and cause a coating to build up. There are a few different explanations for why Moly is used in greases. Some say this is to coat the moving parts in a bearing and protect them when they run out of grease, which would prevent wear. Others say that the Moly actually coats abrasive contaminants to prevent them from scoring the moving surfaces inside of the bearing. Whatever the application-specific reason is, Moly is used because it sticks to other materials and helps protect bearings that are not lubricated consistently.

Automatic lubrication solves the problem of inconsistent lubrication by reducing the human element. Automation allows the lubrication events to be scheduled and monitored so that consistent lubrication is virtually guaranteed. The automatic systems apply a small replenishing volume of grease, keeping a constant film of lubricant between the contact surfaces of the bearing. No more missed grease points, no more lost time and no more dirty grease guns on the floor. With automatic lubrication, there may not be the same need for Moly because every bearing will receive the grease it requires to keep it lubricated and purged of contaminants.

At Graco, we recommend that any grease used in our automatic lubrication systems be limited to 5% solid content or less. Moly is a solid. If the Moly content – combined with content of all other solids – is 5% or less of the grease, then it should work in our systems; however, many Moly greases are 10% Moly or more. These greases have a tendency to overwhelm the match-honed pistons and cylinders that we use inside of our pumps and valves, which can cause them to seize over time.

Graco is a product- and solution-oriented company, not a grease company, but we do offer a grease for the convenience of our customers. This is a solid-free lithium complex grease, and there is a reason for this. Grease compatibility is an issue because of what can happen when two incompatible greases are introduced to each other. This is important to consider when refilling a reservoir that already contains grease. Lubrication grease is a mixture of oil and soap or another thickener. The portion of the grease that determines the compatibility is the thickener. Lithium complex is the thickener that is most compatible with other thickeners. There are only a few other thickeners that are not compatible with lithium complex, when using one of the Graco greases.

Ultimately, Graco does not make recommendations for the grease used in a given application because choosing the right grease is really up to the equipment manufacturer and the customer. But where our pumps and valves are concerned, Graco recommends keeping the total solid content at 5% or less, including Moly content. This will help to ensure a long, dependable life from Graco industrial lubrication products.

SOURCE: Graco Vehicle Service & Heavy Equipment
.

 

[V8srfun]

.
I remember that forever we used Chrome Moly for wheel bearings. There may well be better stuff out there, but of all the things we had go wrong - wheel bearings "going dry" wasn't a problem.

The exception for trucks that were in swamps for months at the time... Even then it wasn't because of a bearing or grease failure. Just that swamp water had a tendency to have tanic acids in it that ate metal over time... (specific mention of purging of contaminants)

I discovered a posting from an industrial Lubrication guy and his "take" on grease is posted below.


Jack Koenig, Industrial Lubrication Field Application Engineer
Molybdenum disulfide (Moly) is a solid additive, most commonly used in extreme pressure applications. The Moly particles are intended to fill in tiny imperfections in the machined surfaces and protect against “welding” during shock loading and heavy loads; however, the material is also known to stick to surfaces and cause a coating to build up. There are a few different explanations for why Moly is used in greases. Some say this is to coat the moving parts in a bearing and protect them when they run out of grease, which would prevent wear. Others say that the Moly actually coats abrasive contaminants to prevent them from scoring the moving surfaces inside of the bearing. Whatever the application-specific reason is, Moly is used because it sticks to other materials and helps protect bearings that are not lubricated consistently.

Automatic lubrication solves the problem of inconsistent lubrication by reducing the human element. Automation allows the lubrication events to be scheduled and monitored so that consistent lubrication is virtually guaranteed. The automatic systems apply a small replenishing volume of grease, keeping a constant film of lubricant between the contact surfaces of the bearing. No more missed grease points, no more lost time and no more dirty grease guns on the floor. With automatic lubrication, there may not be the same need for Moly because every bearing will receive the grease it requires to keep it lubricated and purged of contaminants.

At Graco, we recommend that any grease used in our automatic lubrication systems be limited to 5% solid content or less. Moly is a solid. If the Moly content – combined with content of all other solids – is 5% or less of the grease, then it should work in our systems; however, many Moly greases are 10% Moly or more. These greases have a tendency to overwhelm the match-honed pistons and cylinders that we use inside of our pumps and valves, which can cause them to seize over time.

Graco is a product- and solution-oriented company, not a grease company, but we do offer a grease for the convenience of our customers. This is a solid-free lithium complex grease, and there is a reason for this. Grease compatibility is an issue because of what can happen when two incompatible greases are introduced to each other. This is important to consider when refilling a reservoir that already contains grease. Lubrication grease is a mixture of oil and soap or another thickener. The portion of the grease that determines the compatibility is the thickener. Lithium complex is the thickener that is most compatible with other thickeners. There are only a few other thickeners that are not compatible with lithium complex, when using one of the Graco greases.

Ultimately, Graco does not make recommendations for the grease used in a given application because choosing the right grease is really up to the equipment manufacturer and the customer. But where our pumps and valves are concerned, Graco recommends keeping the total solid content at 5% or less, including Moly content. This will help to ensure a long, dependable life from Graco industrial lubrication products.

SOURCE: Graco Vehicle Service & Heavy Equipment
.

The solid content percentage is a interesting topic.
I did not mean to say that the thick grease caused bearings to run dry but I can see how my comment may read that way. I was more saying that the thick grease does not move from where you place it so if the hub is packed full of grease you will just be wasting grease because you will have a hub full of clean grease and a bearing with used dirty grease side by side. My hope is that my hubs packed full of the thinner grease will get more action and the bearings will get to see some new grease through the service interval.

 

[ToddJK]

The lighter or thinner types of grease may be better for those who live in colder climates and the opposite for hotter climates. I'll see how mine hold up, as my wheel bearings have airplane type grease. All I can say so far is that my hubs have never been hot, just warm, no matter how long I've been driving. I've heard it works better as a lubricant and sudden temperature changes, but doesn't last as long, so I've been told by a few mechanics. When I have to replace my bearings, I'll probably stick with Lucas, just because it seems to work well on everything else.

 

[kenn]

I labored over it and got the masterpro high temp red wheel bearing grease in the 4lb tubs from Orielly using a 30% off discount code.

 

[V8srfun]

The lighter or thinner types of grease may be better for those who live in colder climates and the opposite for hotter climates. I'll see how mine hold up, as my wheel bearings have airplane type grease. All I can say so far is that my hubs have never been hot, just warm, no matter how long I've been driving. I've heard it works better as a lubricant and sudden temperature changes, but doesn't last as long, so I've been told by a few mechanics. When I have to replace my bearings, I'll probably stick with Lucas, just because it seems to work well on everything else.

I would agree for the most part (I live in central pa) so that would apply to me even tho I really didn’t think much about ambient temperature when I ordered the grease.

 

[topo]

I found this on Youtube and would like to share it is time to repack wheel bearings on my M52A2 the last time was 2016 and one hub is getting warm is seams like I just greased them . I used Napa wheel bearing grease for years no problem it is just what I have always used but maybe this Shell S3V220C is worth a try .

 

[87cr250r]

The best grease for wheel bearings is polyurea based. It has a higher oil to thickener ratio so you get more of the stuff that actually lubricates. You may or may not want EP additives for wheel bearings but polyurea is available with them. You don't want EP for ball bearings. The only auto parts store polyurea available I know of is Lucas Xtra Heavy Duty. Industrially, Chevron Black Pearl and Mobil Polyrex EP2 are available. If you don't need or want EP, Mobil Polyrex EM is common. Caterpillar has one called Ball Bearing Grease. Polyurea grease will run about 5x as long as lithium grease. The base oil is thinner as well so if you have a hot running hub it will run cooler.

If you are lubricating a throw out bearing you really must use a polyurea grease because they are shear resistant and resist separation by centrifugal forces. When the clutch is engaged there is no stirring effect to keep the oil and thickener mixed.

Do any modern vehicles use lithium grease anywhere?

 

[pmramsey]

Shell # 5

 

[Adrok]

My HUMBLE opinion...

Do NOT mix grease....No bueno. MANY react with each other, causing compounds to precipitate out, or the grease to lose or develop undesirable properties. The products balance the amount a oil 'liberated' at different conditions. Too much free synthetic oil will not withstand high temp and can weep from micro-pores. Too little will simply not lubricate. Mixing Moly grease with a calcium or aluminum complex ( heavy equipment grease ) leads to hardening and particulates to form.
If you are running the original / older bearing, or do limited high speed / on- road use, THICKER / HEAVIER / TACKIER. Red and Tacky for the win. It reacts very little ( if at all ) with other compounds.
If it is a newer bearing ( modern seals ) and you have a clean slate, with NO concerns or questions of previous wear / damage / use / product: Polyrex grease, or Moly. Better coating, especially for high speed or newer bearings with tighter tolerances.

Cheers

 

[Karl kostman]

I have been using Lucas Red and tacky for all my truck wheel bearings since it came out and its always done a very nice job!

 

[G744]

When one thinks about the environment of a tactical MV wheel bearing, remember they seldom see even 500 RPM. Definitely not a high speed operation.

When you take into account the massive size of the rollers/race vs the loads upon them, a good long-fiber grease properly packed is more than enough to keep them happy for a long time.

How many miles have you put on those trucks since they came to you?

For over 50 years of driving MVs, never have I worn out or had a wheel bearing fail because of the brand of grease it has in it. I'm willing to bet I put a lot more miles on them than most of you. (>25,000 on my M54A1 since buying it)

As to the matter of the grease I've used all those years is Majestic JT-6 for wheel bearings. I use the red stuff is for U-joints, as they turn a lot faster than most trucks due to the high ratio reduction RPM.

Don't overthink this, and a lot of the previous recommendations are valid choices.

My remark of not using Moly grease in MV wheel bearings, as you will probably find gear oil contamination in all or them, more likely in the rears as there is but one seal between hot oil and your grease. Gear oil mixed with Moly will turn into something resembling black mud, with little lubricity.

To my understanding, Moly came along when disc brakes (Hotter running than drum) were fitted.

 

[87cr250r]

Moly is for sliding and journal bearings. It works ok in roller bearings but must not be used in ball bearings.

 

[Jeepsinker]

Seriously, stop overthinking this. Just go grab a bucket of red Mystik JT-6 and you'll have what you need for two full truck hub and knuckle services, and you won't have any issues out of it.

 

[87cr250r]

I always laugh when grease labels itself as "high temp". It's true, high temp greases make bearings run hotter because they have thicker base oils and more thickener. When I have problem bearings that run hot I switch to low temp greases and the bearings run cooler.