So I was doing the rear brakes and come to think I should replace the seals while I have the apart. The inner diameter on the seal is 2 7/8" but I forgot to measure the outer diameter and the truck is back at the farm.
I found one that is 3.307" outer diameter and 0.46" width for a spicer 60 with 12"x2.5" brakes, is this the one I need?

Thanks.

 

I used National 417158 on my '90 D250. Axle is a D70.

 

hey-Hey!!!,
There are two seals for the D70. One for a 3" seal journal and one for the 2.875" Never measured the OD though...
cheers,
Douglas

 

This thread discusses your seal.

There are a couple different choices, based upon size. I think u2slow might be right there, as it was the correct one for mine as well.

https://www.dieseltruckresource.com/...d.php?t=296794


I haven't had one issue since I put the correct seal in there.

 

Thanks for the link, I remember that thread. I believe I need the one that is 2.875", I'll remove it and take it to the store to make sure I get the right one.