How to put some grease in trailer axle bearings, without taking them apart?

It will work, but will a take a huge amount of grease to fill the back bearing, not real practical. I have done that on farm equipment, but the capacity was much smaller.

 

Either get a set of bearing buddies or drill a tiny vent hole so that you do not overpressure the grease and push the seal out the back side of the hub. Bearing buddies are designed for exactly what you intend to do, they have a spring loaded plate to keep pressure on the grease and in the bearings, they also have a vent hole to indcate when the cavity is full.

 

Just google "bearing buddy".

 

your trailer isn't an oil bath system, that uses hub oil? most over the road trailers you pop off the plug and pour in hub oil. it usually light duty trailers with grease trailer bearings

 

Kind of what I was thinking. Most trailer hubs take oil.

 

OP,you forget something.
If it is time to put new grease into a bearing then it is also time to check the wear off the bearing.
So you are not paying someone to grease them,you are also paying him to make shure your bearings are still in good shape.

 

when I bought my flatbed rated to haul 80,000 lbs. it came from factory with grease in the hubs. not oil. 1 bearing went out & I liked the ides of oil better than grease. I had the truckpro cross reference the bearing, race & seal. turned out they used all the same parts. I put oil in the repaired wheel & also put in the other with the grease. yes I put hub oil mixed with the grease already in the hub. it gave me no problems for several years.