Madison Motorsports
Wheel Bearing Castle Nut - Printable Version

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+--- Thread: Wheel Bearing Castle Nut (/showthread.php?tid=11415)



Wheel Bearing Castle Nut - ViPER1313 - 04-01-2017

Looking for some advice here. I have had persistent problems with the front wheel bearings on my Talon - the castle nuts do not want to stay torqued down. The last time I replaced them 10k miles ago, I ran into the same issue, and attributed it to tracking the car 1 day after installing new bearings without re-torquing after installation. When they got lose last time, I battled them repeatedly coming loose until I wailed on them with a breaker bar, far exceeding the factory torque spec. They stayed tight, but the right front bearing ate itself in very short order, from what I can only assume was the excessive pre-load on the races.

I just replaced my right front wheel bearing before coming down to the auto show. I had a garage press in a new bearing into the existing hub and reinstalled with the old lock washer and a new castle nut to factory torque spec (144-188 foot lbs, I set it to 175, checked with 2x torque wrenches). Drove 1 mile, retorqued (it was slightly loose). Drove another 20 miles, it was loose again (it was resting on the safety wire). Drove another 30 miles, it was loose again. I said F-this noise and torqued to 250lbs + another good heave to what I can only assume was 300+ ft lbs. Drove to the car show and back (roughly 150 miles) - after coming off the highway, the bearing was "popping" when moving at very slow speeds (it felt almost like a sticking brake pad.) It stopped popping after (what I can only assume) it cooled down from all the excessive load, nut was still tight. Got home, center of the hub was noticeably warm. I cranked down the nut with a breaker bar, loosened and re-torqued to 150ft-lbs; haven't driven it yet.

What the hell is wrong here? Bearing not pressed correctly into the hub? Hub warn out? Bad alignment eating the bearings? Needs new lock washer? Use loc-tite on the castle nut? I am at my wits end with this project.


Re: Wheel Bearing Castle Nut - ScottyB - 04-02-2017

whoa, weird. not to insult your intelligence, just trying to get a picture here, but this castle nut has no provisions for a cotter pin? that's weird if not.

if the hub was worn i'd imagine you'd just get janky alignment specs but not actually a bolt that wants to exit itself from the car.

for the bolt to loosen itself like that so often my first thought is that there is some kind of expansion/contraction happening that's extensive enough for the bolt to loosen itself even at high torque loads. is there anything else on that hub that would be pouring heat into the hub like a dragging pad?

that castle nut should bolt down on your axle shaft right? i wonder if there is also some kind of play in the shaft that is in turn adding clearance to the castle nut binding area and allowing enough movement that the bolt can back itself off. there has to be some kind of movement somewhere because i strongly doubt that nice new bearings are going to do that to you, and over tightening them is as bad as having them too loose.


Re: Wheel Bearing Castle Nut - Sully - 04-02-2017

Is it possible to drill a provision for a cotter pin? I don't have much experience but the couple times I've seen castle nuts, they've also used pins. I thought that was the point.

How is the safety wire done? Is there a hole through the rod that you have wire through? I guess that's unlikely

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Re: Wheel Bearing Castle Nut - .RJ - 04-02-2017

The cotter pin wont stop the nut from loosening, only from coming off once it does.

Something is wonky in there - either the hub, carrier/upright or axle, or all of them - but any movement in there will cause the bearing to fail prematurely.

Torquing the axle nut down like that should NOT cause the bearing to fail quickly like it did. Its common practice on track cars to torque those nuts to 250 ft-lbs or more.


Re: Wheel Bearing Castle Nut - HAULN-SS - 04-02-2017

Are the thread pitch on the stud and the nut the same?


Re: Wheel Bearing Castle Nut - ViPER1313 - 04-02-2017

There are holes for cotter pins and I have one in there. Like RJ said... the pin stops the nut, but only after its 1/8 turn loose and at 0lbs torque.

Threads on nut are the right pitch. .


Re: Wheel Bearing Castle Nut - .RJ - 04-02-2017

HAULN-SS Wrote:Are the thread pitch on the stud and the nut the same?

Kentucky locknut


Re: Wheel Bearing Castle Nut - BLINGMW - 04-02-2017

A) I don't suppose there's a washer missing?
B) Shouldn't have to, but loctite sounds like a hey-why-not to me


Re: Wheel Bearing Castle Nut - Senor_Taylor - 04-03-2017

Have you looked at the other side and compared? Maybe it's something really simple missing that your mind is glancing over.

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Re: Wheel Bearing Castle Nut - D_Eclipse9916 - 04-03-2017

.RJ Wrote:The cotter pin wont stop the nut from loosening, only from coming off once it does.

Something is wonky in there - either the hub, carrier/upright or axle, or all of them - but any movement in there will cause the bearing to fail prematurely.

Torquing the axle nut down like that should NOT cause the bearing to fail quickly like it did. Its common practice on track cars to torque those nuts to 250 ft-lbs or more.

All this except don't overtorque your wheel bearings. It will lead to wheel bearing failure (honestly your failure sounds different though).


I am of the mindset you have a bad hub or spindle (or installer error :lol: ). Just checking, you didn't put any lubricant on the threads did you? (still think at the torque of the wheel bearing it doesnt matter anyway).


Re: Wheel Bearing Castle Nut - JustinG - 04-07-2017

stop using those 20yr old used talon bearings