8n with too much axel preload

[jzimmer238]

I have a 48 8n that has been in my family for 40 years. I am replacing the brakes and plan on fixing the oil leak into the brakes. I pulled the left axel from the shaft and posted pictures of the differential end of the axel. Does this look like normal ware or was there not enough shims installed? I plan on touching up the ends to remove the sharp edges. Do I need to consider the shorter axel shaft when adjusting the preload?

 

[wore out]

I have a 48 8n that has been in my family for 40 years. I am replacing the brakes and plan on fixing the oil leak into the brakes. I pulled the left axel from the shaft and posted pictures of the differential end of the axel. Does this look like normal ware or was there not enough shims installed? I plan on touching up the ends to remove the sharp edges. Do I need to consider the shorter axel shaft when adjusting the preload?

The axle bearings are NOT "preloaded", the correct setting is three to five thousandths (give or take a little) of "endplay".

The weight of the tractor and the traction loading carried by the tapered axle bearings forces the ends together in use.

When traveling straight forward with matched rear tires the axles turn at the same speed, so there's very little relative movement where they butt together.

Even while turning there's no HUGE speed difference between the shafts.

The greatest speed difference would come about when on wheel "spins out" while the opposite wheel is stationary.

I would smooth the shaft ends, then check for the desired endplay upon assembly and see what you have, GUESSING what to do ahead of time won't solve anything.

 

[jzimmer238]

Thanks Wore Out. I did not realize that the 2 axels butt together during normal operation. Since it is end play and not bearing preload I should be fine as long as there is .002 to .006 of end play. Axel shaft ware would only be a concern if end play was greater than .006 with all shims removed.

 

[Btzj02]

No that is not normal wear. I believe the shop manual has a good description as to how to correctly shim the axles. The result of a correct set up is that when turning one axle in one direction the other axle should turn in the other direction. If both axles turn the same direction you need more shims.

 

[jzimmer238]

Btzj02, thanks for answering my question about normal ware. With the axel ware as it is, are there other components that may have been damaged other than the bearing and retainer that I should check before I put it back together? I understand the endplay adjustment now.

 

[Btzj02]

Btzj02, thanks for answering my question about normal ware. With the axel ware as it is, are there other components that may have been damaged other than the bearing and retainer that I should check before I put it back together? I understand the endplay adjustment now.

My 8N51 had worn axles where they spline to the hub. The splines actually looked very good but when tightened they pulled up to tight. The result was the outer edge of the break shoe rubbed against the drum. I "modified" the break shoes to fix the problem because it looked as if the real fix would have been new axles and I wasn't quite ready to do that!

 

[DN-N-TN]

My 8N51 had worn axles where they spline to the hub. The splines actually looked very good but when tightened they pulled up to tight. The result was the outer edge of the break shoe rubbed against the drum. I "modified" the break shoes to fix the problem because it looked as if the real fix would have been new axles and I wasn't quite ready to do that!

I had the same problem on my old NAA, so, I did a short term fix till I could get some hubs. I removed the drums and install 5/8" flat washers between the hub and the drum on the lug bolts to space it out some. The fix worked well enough that I left it like that for the next twenty years (still there). Everything stays tight with no scrubbing noise.