I have to agree with arron on this. If you have grease in the front of a 4 wd tractor, how is the grease going to get down to the bearings in the front wheels?These roller wheel bearings need to be soaked in a liquid gear oil.If the seals are leaking , replace them. I guess you could pack the wheel bearings in the front like a car,but then there are the gears that need to be lubed also.