Ways to determine grease compatability

[tractchores]

I have a trailer that is new to me and I want to add some grease to the bearings. I have no idea what type of grease is in there already. Is there a way to tell if the grease is compatible by mixing some of it with the new grease or any other methods when one type is unknown? Trying to avoid a repack as the bearings and existing grease are in good shape, I just want to add some.

 

[Einthewoods]

This likely won't be helpful, and I'll probably get stomped on by some PhD wheel bearing grease expert.... :laughing:

I wouldn't give it any thought and use whatever wheel bearing grease you have on hand.

 

[Beltzington]

I don't have and answer but like most of us I do have an opinion

Ask the previous owner, if they don't know you likely need to start fresh anyway. Even with similar base greases the manufacturer is hesitant to guaranty compatibility with other brands, you see words like "most compatible" etc. they all recommend starting with clean hub when changing brands. I'll play devils advocate, what are you going to do if you can figure out what is currently in it? Buy a second grease gun for one trailer? I hate messing with grease guns and tubes and I have an expensive Milwaukee powered model.

I'm assuming the hubs have a grease fitting and you will be pushing the old grease out. If this is the case I agree with Einthewoods keep adding grease until the color remains consistent and don't worry about it.

 

[Tractor Seabee]

Wheel hubs are not a good place to mix grease; especially if the existing is an unkown. Take apart, clean up and re-pack with the proper lubricant for the application. Ball and roller bearings are also vunerable the mixe grease. Metal to metal surfaces not so much. Definately don't mixed cley base greases with others. They also tend to harden with age and plug up the passages.

Ron

 

[Mace Canute]

Wheel hubs are not a good place to mix grease; especially if the existing is an unkown. Take apart, clean up and re-pack with the proper lubricant for the application. Ball and roller bearings are also vunerable the mixe grease. Metal to metal surfaces not so much. Definately don't mixed cley base greases with others. They also tend to harden with age and plug up the passages.

Ron

This is very good advice. :thumbsup:

 

[tractchores]

Figuring I probably just have to repack these... no way to contact the guy I bought it from. I was hoping I could scoop some grease out and mix it with the new stuff and see what happened.

 

[yomax4]

I have to do the same with a new one I just bought. Sucks for sure but piece of mind is king out on the highway.

 

[Fallon]

How to Understand Grease Compatibility

Pile of other similar charts out there. But that isnt super helpful if you dont know what's already in there. Lithium complex is the least likely to cause any interaction problems.

 

[sixdogs]

It's unfortunate but you have to start over and clean the bearings and old grease and start with what you know. That's what I've always done. You could have the old string grease or who knows what. I've found dried out grease lots of times and to just grease over that wouldn't have worked.

 

[kenlip]

How to Understand Grease Compatibility

Pile of other similar charts out there. But that isnt super helpful if you dont know what's already in there. Lithium complex is the least likely to cause any interaction problems.

Even the charts can't be relied on with confidence.

How to Determine Grease Compatibility and Why It's Important - Machinery Lubrication India