Fruehauf wheel bearing torque

[caterpillar guy]

I'm having a problem with a couple wheel seals leaking on our dump trailer. I have always just tightened them up till I could not turn them or they turned hard, then back off till I could turn them smoothly and reasonably easy not to easy but easy with a bit of drag sort of. Any one who has done semi wheel bearings knows what I mean. These are Fruehauf axles on a 98 or 99 tri axle dump trailer an old coal bucket so it has the bigger axles with the 7foot high sides and lots of space. We changed over to the hub piloted wheels last year and dropped it down a bit with short 22.5's instead of the tall 24.5's. I was looking for a better way to torque the wheels bearings. It has the big 8sided nut with about 4inch od nut. I tightened it up till it was tight and could still turn it albeit was stuck for a second then turned reasonable with a drag like it might be to tight. I am thinking they may have been to loose for the reason the seal went to leaking since I can't find a problem with the seal nor the wear ring on the spindle. Any ideas welcome. I'm going to close it up for tonight and see what the results are before closing it up for permanent.

 

[Phil9N3667]

If you can feel any end play with just the hub on, snug it up to the next hole and put the cotter pin in if it's the old style nut. Otherwise, a few foot pounds of torque is OK. Use a CR/SKF seal that has no wear ring and I believe you'll be rid of the leakage issue. Otherwise, pack it with grease!!

 

[Phil9N3667]

This is what I've found to work for me and I've had very few leaking seals and NO bearing failures in almost 46 years of doing wheel ends.

 

[caterpillar guy]

Phil I ran over the road for a lot of years and local Detroit to Chicago daily for several before that and found the only seals that lasted over time on my trailers were the Stemcos with the wear rings. I have tried all of the C/R,national ,barrier,mechanix,and any of the others I left out. 3 years was the max on them. The Stemco's will go 10 years with good results. I don't know what happened with these 2. I put them in the same way /I did with the rest of them. One difference I can see is the axle looks like it has some kind of a sleeve or ring that is part of the axle for the wear sleeve to go onto. The wear ring goes on like it should not to tight nor to loose and seems to fit. I did put some permatex on the spindle and wear ring this time which I have not done on the last 20 years. I did not use it on the seal though. If that place is out of round a wee bit I suppose it could cause it to leak but then would not the others also? When we changed hubs last year it had those seals with the rubber on the spindle side of the seal that turn inside of themselves. Maybe I will have to go to those. Don't know.

 

[caterpillar guy]

Phil I've been playing with wheels close to that long when I started in the 80's with my tandem and working for another farmer fixing his trailers. Probably not near as many axles as you though.

 

[Janicholson]

When it is in the too tight mode, hit it with a heavy blow that sets bearings and races deep against their ridge, This can result in a more solid adjustment when backed off to modest force spinnng the wheel. Jim

 

[wore out]

Contrary to common opinion, generally, bearing mfg's such as Timken recommend one to three thousandths of endplay for HD wheel bearings of the type you are dealing with, rather than preload.

 

[caterpillar guy]

Wore out I was reading that on Timken's website in a PDF tonight. I just don't see how you would wiggle a hub that heavy to read that fine a measurement alone. And I don't have a magnetic base for a dial indicator to read it. I set it by tight then check that it would turn okay and closed it up with the ring on the nut and set on the tab on the inner nut and locked the outer to it then put the little screw in the ring with the lock tab for the keyway and holes in it. I'll see about pictures tomorrow of the other one I have left to do. Pictures of before,during and after.

 

[MARK ROBKE]

I worked on trucks and trailers for forty years-done countless wheel seals. CR seals, hands down are the best. In the 70's we used Stemco with the wear rings on the axle. We even had a fleet that needed seals constantly-until we switched to CR. But there should be no preload on a wheel bearing; about .003 is the spec. I was taught how to 'feel' end play, by setting on my heels and bouncing the wheel assembly with my knees. You will hear a little clunk noise, each time you bounce the wheel, if you do it right. If it had 2 nuts the inner would be loose, with more end play, and when you tightened the outer nut, you would get your'.003'. Later axles came with single nuts with a built-in lock that the socket released when you put it over the nut. This nut had a specific torque, that I do not recall, but I think it is on the face of the nut. I think there are some variations of nut, but we had very few to replace in my last years, due to better design, I guess. We also were taught to set up the dial indicator with the magnetic base, but I could check myself with the 'feel' method and be right on. Another thing that is very important, is CORRECT seal installation-using the correct seal driver, and making sure the seal is bottomed correctly and not mashed in. Mark.

 

[moresmoke]

Tighten nut tight while turning to seat bearings and seal. Back off 1 turn, retorque to 50 ftlbs while turning, back off nut 1/4 turn. Install locking ring and jam nut. Torque jam nut to 3-400 ftlb.

 

[farmer656]

while tightening the nut spin the wheels , this loads the bearings you have done enough to know when it is correct , you have what they call a propar axle