[GreinTime]

So this just got towed into our shop!

Spindle end




Wheel seal outer ring... supposed to be interference fit into back of hub for those who don't know, not the whole way against the backing plate lol. There is no seal at all left, inside or out. The garter spring actually melted...


Outer race- kind of... its not really there, I'll show you the resultant damage to the innards in a second here


Actual spindle surface. Note that it is totally dry, with no residual oil left.


Drum after brakes had locked... hard. There is actually drum lining on the bottom shoe from where it tore it off the drum on the inner side of the shoe.


Air bag complete with hole from fire!


And finally, the moment you've all been waiting for! This is what's left of the bearings. The rollers are the thicket chunks, obviously, with the races being the wafer thin strips you can see as well. All damage to the hub cap was caused by bearings rocketing out the end of the hub.... YIKES!!!!


My tech thinks that the spindle nut was over tightened, however I personally feel its the opposite with how compressed the bearings are. There were little to no metal shavings/particles in the hub like I feel like there would have been had the bearing burned out. I doubt I will be here when they come and weld a new spindle on, but if I am I'll ask the Axle Surgeon if I'm allowed to snap some pics of his jig and stuff. Its pretty cool and its definitely not something most people are exposed to in their normal working environment.

[GreinTime]

Also, for sake of clarity, that is a 4 1/4 inch nut, and was pulled 1/2 inch out on one side, and the curly q you see in the first pic is part of the threads from the inside of the nut/outside of the spindle!

[Otto Nobedder]

You'll be stunned to know the preload specifications the company your dad works for calls out. 50 lb/ft on the preload nut(!!), and 250# on the locknut, with 50-wt synthetic transmission fluid as lubricant, underfilled almost 50%.

This works flawlessly, to my amazement, with Timken bearings, but fails every time with Chinese bearings.

I've seen similar damage on hybrid builds, like Hendrickson axles with hubs made in Pakistan (casting sand still present inside) and Chinese bearings. I warned, and was ignored. The trailer made it 35 miles.

Steve S

[GreinTime]

I feel ya man. As it turns out this was actually a unitized hub and we can't get one for 6 weeks. So I have no idea what the company is doing with it as it is not here right now.

With ConMet preset hubs (inner bearing, spacer, outer bearing) you torque the bearings to 250 lb/ft and leave it...granted they are preloaded by the spacer and are fine as long as endplay is between .001-.004in. With a traditional 4 piece retention system, Freightliner calls for 100 lb/ft while spinning, re-torque to 100 lb/ft twice while still spinning both directions, back it to 0, don't spin, and then torque to 50 lb/ft while spinning and finally back it off 1/6-1/4 of a turn. Then put the lock ring in, torque the outer nut to 300-350 lb/ft (or as my dad would say,"Just fu¢king jump on a 3/4 breaker bar until it won't turn anymore" lol). I was astonished as I was going through the manual.

This hub nut --- 500lb/ft as stated on the hub and nut.... that is a LOT of torque lol