I am puting new axle bearing in a f600 ford truck rear. Do i need to pack the bearings with grease? Or do i just pour 90w oil on them? If anyone can help i would really appreciate it very mutch. I need to put them back in tomorrow. Thanks Alvin.

 

On my 1958 F600 with Eaton 2 speed rear axle the bearings are greased and there is a seal on the outer end of the axle to keep the rear end oil out of the bearings. Depending upon which rear axle is in your F600 that may be true or not.

 

I always pack the bearings when i instal them
I also quit using the axle end seal decades ago and lube the bearings with oil in the hubs.Use oil seals instead of grease seals

 

My truck is a 1973 ford f600 with a two speed rear end.

 

I use a synthetic mobil 1 all purpose grease on my bearings. Never heard of using gear oil on them, doesn't seem any where near sticky enough to stay in the bearing assembly, thats why bearing grease is thick.

 

How often is the truck going to be used. If seldom, I would use grease and the axle seals if you have a choice. If you are going to use the truck everyday, as stated above use oil seals on the hub and leave out the axle seals. The oil will migrate back and forth down the axles to lube the bearings. If you haven't removed the hubs yet, I think you will find that it is probably this way(fairly recent axle) it already is. If you do decide to go the oil bath route, it won't hurt a thing to lightly pack the bearings with a little grease also.

If the rear has any kind of limited slip/locker in it do not use synthetic oil in it. You will destroy the clutches(Too Slick for heavy duty applications).

There is a reason that tractor trailers run all oil bath hubs. The bearings stay cooler and last longer.