View Full Version : Broken hub bolt

April 3rd, 2008, 21:06
Oh damn.

I have sheared one of the 3 12 point 13mm bolts that holds the hub to the knuckle. The bolt sheared about 5mm down from the head. It is about halfway into what appears to be a slight taper (widening) of the bolt at the head end.

So I have the remainder of the bolt recessed about 5-10mm into the knuckle (from the back side) and the little nub of threaded bolt sticking out of the hub. I intend to replace the hub with a new one I have.

I've already realised the bolt isn't threaded in the knuckle... it only threads into the hub, correct? Since I sheared OFF the bolt head, technically the bolt is no longer securing the hub to the knuckle. I figure if I can release the remaining two bolts I can pull the hub off as usual. However, I worry that the taper near where the head of the bolt was will not pull through the hole in the knuckle (like, does the hole in the knuckle "taper-down" to snuggly fit the bolt?)

Oh, someone give me a yell on this one... I really could use some help here.

April 3rd, 2008, 21:21
If you take the other two out can you pull the hub off? Remeber the hub will rust to the knuckle so if you meet resistance it might not be the bolt. As I recall the bolts are only half threaded, so no they don't thread into the knuckle....

Blaine B.
April 3rd, 2008, 21:57
It should come out. X2 on the hub rusting to the knuckle if you are met with resistance.

April 3rd, 2008, 22:00
Yeah, pull the other two, and then it may take some massaging with a bfh to break the rust free, but that guy should slide right out of there.

EDIT: You live in Mass... Yes, it is a ginormous PITA to get the hubs off in the rust belt.

I highly recommend you grease the mating surfaces when you re-install.

April 4th, 2008, 08:31
see this wrieup about how to get it off without much trouble. I had to do this and Van of Vanco (as in the Vanco brake kit) pointed me here.

April 4th, 2008, 17:37
Here's the update:

After snapping one of the hub bolts near it's 12pt head, the majority of the shaft was seized in the bore running through the knuckle. The threaded tip was threaded into the hub. I had no way to back the bolt out and it would not just slide out like I had hoped (too rusted). The other two bolts removed with less trouble. So I had the hub hanging on by one seized up bolt.

I had to hack saw between the hub and the dust shield/knuckle. Once the bolt was cut, I had a free hub and the mother of all rusted bolt shafts lodged in my knuckle. I removed the knuckle and took it to the driveshaft shop that did my axle u-joints. They were nice enough to bring the knuckle out back and press out the bolt shaft with a 100-ton press! :yelclap: The gentleman that helped me said he'd never seen one of these bolts lock up in the knuckle so badly... he said it was amazing how much force it took to shoot it through. Never in a million years would I have gotten that sucker out on my own. Took some pretty hefty heating too. Many thanks to Dan at Mitchell Differential in Shrewsbury MA. Picked up new hub bolts at the dealer for $7 each.

Anyways, the hub is out, the knuckle is out and restored to life and I'm moving ahead with my ball joint job. What a day... much thanks to the responders.

BTW: I used the extension/turn the wheel trick on my other side hub and it popped free with no sweat.