Forum Discussion
katysdad
Mar 16, 2014Explorer
Oasisbob wrote:
I to not consider using the grease fitting more than a false sense of security as I doubt much grease gets to the rear bearing. I proved this once on my boat trailer by using a different color grease then tearing the hub down to see. Grease put into the outer fitting never made the trip to the rear. May I ask of others why we service trailer bearings more than those of the tow vehicle?
Boat trailer bearing buddies with the zerk in the bearing cap were only designed to keep slight pressure in the hub to help prevent water intrusion into the hub. Todays axles with the fitting in end of the spindle send the grease to the back side of the inner bearing thru the center of the hub and then to the outer bearing. They work very well if greased properly.
How they work
If you have not repacked bearings recently I suggest putting in new quality grease seals with double lip before you follow the below procedure which is from Dexter Axle.
E-Z Lube⢠Lubrication
The procedure is as follows:
1. Remove the rubber plug from the end of the grease cap.
2. Place a standard grease gun onto the grease fitting located in the end of the spindle. Make sure the grease gun nozzle is ful
ly engaged on
the fitting.
3. Pump grease into the fitting. The old displaced grease will begin to flow back out the cap around the grease gun nozzle.
4. When the new clean grease is observed, remove the grease gun, wipe off any excess, and replace the rubber plug in the cap.
5. Rotate hub or drum while adding grease
"May I ask of others why we service trailer bearings more than those of the tow vehicle?"
Because they don't pack enough grease from axle manufacturer.
When packed correctly (fill center of hub between bearings with grease) I have never had bearing issues. I pulled wheels on a friends trailer recently and honestly don't know how it made it from factory to east coast. Hardly a trace of grease on seals and what was in the bearings would not fill a thimble. Center of hubs were completely dry.
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