I'm refurbishing the rear end on my '56 Mercury and have a question regarding the oil seals. When I pulled the old ones (originals?) out, the feather edges were facing out, meaning that the flat sides of the seals were facing in towards the differential.

It seems odd that one could install the seals with a seal installer (dowel, etc.) and not wreck the rubber feather edge. It would make more sense to have the flat side out, so that installing the seals is as easy as doing the front hub oil seals. The '56 manual was no help as it shows no detail for the seals.

Does anyone know the answer to this one? Remember that the hypoid oil does not flow out to lube the axle shaft bearing; I think this packed with grease when reinstalling.

Confused,

Dave

 

The lip on the seal should always face the fluid it is designed to seal. On a rearend housing this normally places the flat side of the seal to the outside. It appears that the seals on your truck were installed backwards.

 

Viking, thank you very much. I called two F-100 specialty dealers and neither could answer the question.

One more related question: the 1956 manual (pages 172-179) doesn't detail if the axle shaft bearing should be packed with grease before reinstallation. It only mentions to "lubricate the bearing bore".

With gear oil now being kept away from the outboard ends of the axle by the seal, I would assume that the bearing has to be packed with grease to run with any reasonable life.

Your comments, please.

 

The axle bearings are sealed, and lubricated for life. Be sure you put a thin coating of gear oil on the lip of the seal before you install the axle, so it won't run dry at first. Steve

 

Thanks, Steve.

I'll be soaking the seals in 80W90 for 30 minutes prior to installation, as per the book.

Thanks again for the reply.

 

after you put the seal in. it would be a good idea to run a bead of silicone around the outside of the seal between the seal and the "carrier" housing. when I installed mine, one side started dribbling dif oil out over the next few weeks, running that bead of silicone stopped the problem cold.

 

Everyone:

The seals went in perfectly using a seal driver kit and a three-arm gear (or harmonic damper) puller.

Soak the seals in engine oil (not the 80W90 I mentioned above). Use the adaptor from the kit that fits your seal, set the puller to pull against the hub flange on the axle tube, and the rod of the puller smoothly and positively inserts the shaft into the recess. No hammering, and the use of the puller ensures that the seal is parallel to the axle recess.