My F350 4x4 front Axle has a seal just inside the universal joint behind the Brake rotor and the seal seems to be torn or parted,not the seal on the locking hub side but the axle tube end.also the axles seem to have some movement in this area if I grab it and move it .is that normal and has anyone else noticed that seal going into the axle tube being bad.
I really can't figure out how it would even create a good seal if it was'nt torn cause it does'nt really seem to seal at the tube end? cause it spins as the axle rotates in 4x4 mode.
Nothings leaking I just don't want crap getting in there.
Any help would be appreciated.
Thanks.Steve

 

Hi Steve,,

Sounds like your referring to the axle tube dust seal.. About 3" in diameter? Usually don't see late model/lower mileage seals coming apart, but pretty common in older builds and even more so if the 4x4 is used consistently or severe duty.. They will eventually split, and the outer most portion of the seal will just 'tumble' around on the shaft.. Or,, they can dry out and wear the contact lip off then aren't real effective for sealing other than blocking large trash from entering the tube.. The seal is pressed onto the axle yoke, and when the axle is installed the seal lip is forced against the axle tube opening for seal tension.. The inner axle seal (installed from inside the diff housing) will keep the lube back and resist the debris/water.. When I reseal a front axle, I usually see dust/rust/debris inside the axle tube even when the worn seal is intact.. Certainly worse when the seal comes apart, but the internal tube gets cleaned before the new seals go back in.. If it's not leaking gear lube out of the tube, I wouldn't worry about it since sometimes pulling the front axle to change the dust seal can cause the inner axle to leak if debris is pushed or run into the seal during the axle install or if the inner axle seal looses is seal.. Not worth the work involved IMO to change just the dust seal, but understandable if you want to.. Is yours ESOF? Some axle end play is normal...

 

I am getting ready to have my 3rd dust cover put on my 05 f 350. I am glad to hear it is really not a hole lot to worry about. So maybe I will wait now that I have to do the work now that the warranty is up. Does anyone know if there is any service bulletins or recalls on this issue?

 

Weather or not its a worry IMO,, really may depend on the amount of off roading you do and the conditions you do it in.. Only occasional use, or if heavy mudding/severe duty, deeper water ect. although the seal really isn't a water tight seal.. It would certainly be better if the seal 'stayed' intact to hold back the elements,, but they dry out, drag, then rip on the 'thin' flexable sides leaving the contact lip portion spinning on the yoke.. I took a walk around the parking area with my trusty camera and found 2 trucks out of about 6 with blown seals that aren't in for axle reseals.. Most owners never even know their gone.. If I were only using the truck for 'normal to light' use under 'reasonable' conditions then the dust seal wouldn't be a big worry for me..

Here's a pic of the one of the trucks, and the seals hang'n.. Notice that the contact lip is in fairly good condition, and the seals thin sides (works like a bellows) has failed and torn.

 

So if I do not do any serious off roading will I be ok. However I do use the truck to plow , do I really need to worry or just keep an eye on and if it starts to leak the worry , and get it fixed.

John