Wheel seal leaking again in 50k?

If it's any consolation, I've never had any luck with national seals .Like really no luck, hate those things.
I use skf/CR. Never a problem.

 

I know a lot of people around here have been changing out the oil for 00 grease in trailer hubs that sit for long periods like storage trailers and container chassis. 00 grease is thicker than oil and is what they call semi-fluid. The theory is that it won't leak past the seals as easy.

 

Are you using those one piece Stemco seals, by chance?

 

a few things to pay attention too, look for a grove worn in the surface of the spindle where the seal rides, if one is present use a seal with a wear sleeve, also bearings as well as races. look for races that have spun if they have a few dings with a hammer and a punch will typically cure that problem. also bearings close inspection if in doubt replace them. now is the time to do it if you have it apart. my truck has over a million on it so i normally just throw bearings and races in automatically on any seal job. also proper bearing pre-load is critical.

also apparently making sure you bend the lock tabs over isn't common sense. had new s-cams and bushings put in one of my tri axle trailers a few month's later i started loosing a bunch of wheel seals, found not one lock tab was locked and all my bearings were loose, one lock nut had backed itself completely off and was rolling around in the oil bath hub cap.

 

on local trailer we installed 4 different wheel seals. All hubs had mobilith 007 inside and properly adjusted. National (standard version) started to leak at 110k miles. SKF PlusXL started to leak at 180k and it was leaking from sitting area. SKF Classic went 240k miles. National 38 series gold is not leaking yet. it has almost 320k miles now.

 

I am not a big National fan but I do not have their tooling. Normally use Stemco Grit Guard with great success. Probably do not have the correct tools for some Mack drives. Have had some problems there.
CR and SKF are the same company any more. Those metal drive in seals are very good if the surfaces are OK and I have some tools.
If you have no tools get some push in seals.

 

A shop I worked at years ago did a bunch of seals on one before someone figured out the hub was cracked.

 

I realise that This is An OLD thread. But, have you checked to see if the Axle breather isn't blocked/clogged with crap..