The ball joints got loose on my diesel 1 ton dually dump bed, so I took it apart to put in new. I noticed the inner seals are worn so will put new ones in. I wonder if its a good idea to inject some new grease into the bearing and if so is there a special kind or will any good bearing grease work. The existing grease is 23 years old or so... The bearing is still perfectly tight and smooth at 120,000 miles.