Front Hub Bolt Repair Question

[fjryan]

I'm disassembling the front hub and when I remove the hub bolts to separate the rotor from the hub, I discover that some chicken f#cker forced a 1/2" x 13 bolt into the axle hub and it doesn't appear that the redrilled or tapped the hub before doing so. I'd like to repair it with a helicoil and hopefully get a OEM bolt to go back in there (Bolt Flange - Toyota (90080-10395)). My question is for the repair. Is the OEM bolt a M12x1.25 or M13x1.25? I don't have a way to figure the diameter but the threads are 1.25. Any help will be appreciated!

The involved components.

Mr Toyota's fine equipment on the left and, on the right, the unfortunate result of some marginally functional mouth breather that should have been put down at birth.

Thanks in advance!

 

[I Lean]

The brake caliper bolts are M12x1.25 for sure...so try to thread that bolt into the caliper mounting holes and see.

I'd be surprised if they weren't 12mm also.

 

[JunkCrzr89]

M13 is damn near an obsolete size, since it’s basically 1/2”. I’d go all in on the correct size being M12. Home Depot, etc have cards in their nuts and bolts aisle that you can use for free to determine the size. Just take one of the correct bolts in there and measure it.

 

[2001LC]

It is a M12X1.25. I just busted my thread restore tool in one I'm doing now. I've got wheel hub at the machine shop now, to have tool burnt out a helicoil insert job done.

Service: Wheel bearing, Steering Knuckle, Rack OE rubber mounting bushings, Ball joints, Transmission flush W/Surprises!

forum.ih8mud.com

 

[cmck]

I hate when I break up a “set”, of anything. I love when I correct something done wrong by doing it right, even if I was the one who did it wrong the 1st time.

 

[2001LC]

I find loose or a cross thread bolt here about 20% of the time. One I'm working now is the worst and first busted I seen.

Cross thread happens for one reason. Not starting thread by hand, and at least three full turns. Clean threads can almost always be threaded all the way on by hand. These guys at brake shops use impact wrench to start and finish. They don't even know what a torque wrench is. It is fast but should be a criminal offense.

 

[fjryan]

Yup. Thanks for the help, fellers. The caliper flange bolt and O’Reilly’s confirmed it. Now to get a helicoil set.

Any recommendations for a home mechanic that’s only work on metric cars for the foreseeable future. Trying not to spend a lot but I’d guess this won’t be the last time I deal with this issue.

And 2001LC, if they do criminalize it I hope they nab the monkey that honked mine up.