Bearing Grease--What's the diff?

[surveytech]

Whats the difference between Red grease and White grease. Both are labeled for bearings, both say they are Lithium based but they seem to be slightly different. (other than color).

Red seems to be more tacky or clingy (is that a word?) and White seems to be more creamy. Sorry for the lack of technical terms.

I pulled the manual for my Dexter axle and it has a list of recommended grease for the bearings. Brand XYZ was on the list and its a red grease. The bearings came packed with a white grease. I know not to mix the different greases but.....

Is there any difference?

Thanks,
Walter

[asianflava]

Hmmm my Dexter was packed in red grease. Several board members said not to trust that they were done properly at the factory so I repacked the bearings in my new axle. Just so happened that the bearing grease I got from the auto parts store was red also.

High-Temp? Moly Grease? Sorry, I don't know the difference either.

[bledsoe3]

My bearings didn't come packed and I used black grease.

[Dale M.]

I use Molybdenum grease for my bearings and CV joint applications... Usually its recommended for hight temperature applications associated with wheel bearing where disk brakes cause higher temperatures .... I would say to look at "application temperatures" in grease specs and the higher the temp the better it will stand up to use...

Never like the idea of lithium "white grease" for bearing applications...

Dale

[surveytech]

I use Molybdenum grease for my bearings and CV joint applications... Usually its recommended for hight temperature applications associated with wheel bearing where disk brakes cause higher temperatures .... I would say to look at "application temperatures" in grease specs and the higher the temp the better it will stand up to use...

Yes thanks......thats what it sez on the can

Never like the idea of lithium "white grease" for bearing applications...
why would this be bad?

Dale

[Geron]

I prefer the molybdnum as per Dale.

However, the only hard and fast rule I follow with wheel bearing grease is

DO NOT MIX different greases. If you change grease clean and wash the old out before putting in the different grease. (A good idea if you use the same grease)

I don't know why, I just follow that rule.

g

[bobhenry]

Molybedenum Disulphide is a metal it is added as a ultrafine powder at 3 to 15 % by weight to the grease base. It is an excellent assembly paste at 45 to 60% blend. I dry coat pistons and crank bearings with just the powder during engine rebuilds. The reason to not mix greases is that there are about 6 popular familys of grease based on the method of suponification. A bentonite clay based grease will literally fall apart if mixed with the likes of lithiam or bariam based grease even with just small amounts of the contaminating remains. So always clean thoroughly and inspect the bearings for any abrasive scratches. Clean the hub assemblys as well . Resist the temptation to spin the bearing dry with compressed air (They can literally explode ) .
The red dye is to indicate the addition of a tackafier. ( yeah it makes it tacky or sticky if you prefer). The white is lead oxide usually used on areas where we folk may come into contact with it like car door hinge and door locks. White grease is more of a general purpose grease and I would be real reluctant to use it in a high temp situation. A moly/lithiam base grease would be my personal choice.

I worked 2 1/2 years in a lubricants lab blending and testing greases and lubricating oils and paints. Later managed the blending plant in Fort Worth.

[Steve_Cox]

Thanks Bob for the great info.

I experienced disastrous ($120K) results once from someone mixing two types of grease in the bearings of a 4 stage compressor. It had lithium based grease in the bearings and a calcium stearate based grease was added. It caused the oils to bleed out of the greases as they mixed under load and speed, causing bearing failure. Trouble with mixing different types of grease is it is hard to get a definitive answer to compatibility questions, So the absolute safest thing to do if you use a different type is a complete replacement. Would I do it on trailer bearings? No probably not. I would use high temp grease that was made for wheel bearings and not worry about it too much. Might be looking for bleed out at the seal after running a while just to be safe.

[Geron]

Molybedenum Disulphide is a metal it is added as a ultrafine powder at 3 to 15 % by weight to the grease base. It is an excellent assembly paste at 45 to 60% blend. I dry coat pistons and crank bearings with just the powder during engine rebuilds. The reason to not mix greases is that there are about 6 popular familys of grease based on the method of suponification. A bentonite clay based grease will literally fall apart if mixed with the likes of lithiam or bariam based grease even with just small amounts of the contaminating remains. So always clean thoroughly and inspect the bearings for any abrasive scratches. Clean the hub assemblys as well . Resist the temptation to spin the bearing dry with compressed air (They can literally explode ) .
The red dye is to indicate the addition of a tackafier. ( yeah it makes it tacky or sticky if you prefer). The white is lead oxide usually used on areas where we folk may come into contact with it like car door hinge and door locks. White grease is more of a general purpose grease and I would be real reluctant to use it in a high temp situation. A moly/lithiam base grease would be my personal choice.

I worked 2 1/2 years in a lubricants lab blending and testing greases and lubricating oils and paints. Later managed the blending plant in Fort Worth.

Heck, I knew there was a reason I didn't mix greases. I just didn't have all the words and couldn't put them together right if I had them.

Thanks Bob,

Edited:
Oh, BTW, also used Moly working on adult air rifles (Beeman, BSA, Etc). Used it to grease the pistons and springs. High compression and High temps. Oil (petroleum base) would detonate.

[surveytech]

Bob Henry thanks for the excellent explanation! I knew someone here could set me straight about the this.

Thanks!

Walter