Caliper Mounting Bolt / Steering Knuckle Question

I have a 2006 DC 2wd with 195,000 on it.

I was replacing my front brakes yesterday with new Advics rotors and pads ordered from Rock Auto.

Anyways, on to my problem - when mounting the passenger side caliper back on, the top mounting bolt stripped out. As a temporary solution, I ran to the auto parts store and bought some M12-1.25 x25mm bolts, they didn't have any of the flanged head bolts in stock, and my plan was to order some from Toyota online and get them here sometime next week.

However, I can already tell that the mounting hole for caliper bolt (on the knuckle) is not going to hold even a new bolt without stripping out. I managed to get the bolt in, but I did not attempt to torque it to specification for fear of stripping it out, as I can tell it is going to keep spinning.

Obviously, I am avoiding driving the truck until this issue is taken care of.

What is the best course of action here? Try a time-sert or Heli-Coil? Thread a larger hole into the knuckle? Or just replace the entire knuckle (trying to avoid this)?

Also, I just replaced my LBJ w/Toyota OEM and new tie rod ends.

Appreciate any advice in advance, thank you!

 

Yes.
Or just replace the entire knuckle
This is your second and only other option.

 

Heli-Coil or time-sert, do not drill and tap for a larger bolt. I've come across drilled and tapped over sized caliper bolts on other vehicles and what started as a quick job of replacing a caliper turns into a huge pain in the ass because that oversized bolt won't fit a stock caliper. If you do have to replace the knuckle later, you'll be looking at a new caliper as well. Drill it out and use an insert, put thread lock on it, personally I'd use red, and mark the bolt with a paint pen after you torque it and check it periodically at first. If it won't take the torque or ever starts getting loose, replace the knuckle.

 

If you do replace the knuckle, make sure you get one that's the same ABS setup. It's either drilled for an ABS sensor or it isn't.

 

@jbr98 just converted his 2WD to 4WD and may have a good knuckle to sell you.

 

FYI, 2wd and 4wd knuckles (spindles) are exactly same, but use different bearings. It's a huge pain in the butt to press the bearings in and out though. Like bfunke mentioned, finding a good used 2WD is the best. And what Shifty said about getting a knuckle that has the hole for the ABS sensor. I'd choose a Time Sert any day over a helicoil if you went that route, which i would definitely attempt first.

 

yep, L&R in good condition.
Let me know if you need it (op). Located in San Diego area.

 

Thanks for all the great replies, I appreciate it! I will try a time sert first and see how that goes.

 

Update - I was able to install a 15mm long time-sert (M12-1.25) into the steering knuckle. I also ordered some 24mm long inserts, but they were too long, so had to use the 15mm length.

I don't think I tapped the hole perfectly straight, because I could not get the insert to sit perfectly flush with the surface. It was still sticking out a very small amount (maybe 1mm or so). Since I couldn't get the insert all the way in with the insert tool, I also tried turning the insert further in with some pliers, but was only able to make a small amount of progress. I used red threadlocker while installing the insert.

Just a note about drilling and tapping in case anyone else sees this in the future, near the end of both drilling and tapping the hole, it became extra difficult, like the steel was harder in that area (not really sure why or how).

I went ahead and proceeded, and the caliper bolt fit into the threaded insert easily through the hole in the caliper. I applied red threadlocker to the caliper bolt and was able to torque it to ~70 ft-lbs or so. I decided to not go any further with the torque since the insert doesn't have the same amount of threads as the original hole did.

Anyways, all seems to be good for now, I have been driving the truck the past couple of days without issue. Thanks again for the help!

 

It will probably be fine. If the Timesert is sitting proud you may need to file it flush so the caliper sits true against the machined surface. You may want to pull the wheel and check that the caliper is sitting true and tight in a couple weeks after driving it.

 

Good idea - I hadn't thought of filing it flush with the surface, thanks for the suggestion.

 

Reco'd similar to @Weagle when he ran into an issue with his (tensioner pulley?) washer preventing the tensioner from pivoting. File will take you a long way when you need precision fits, things are off-kilter. Just gotta remember what you did next time, if the part is something you can remove and potentially orient wrong next time!!

 

I can’t imagine not using this as a great opportunity to order a knuckle on eBay, press in a new bearing and UBJ and having piece of mind long term.

 

Were you using an impact driver to install the bolts?

 

No, I always start bolts by hand first due to prior bad experiences using an impact incorrectly. I will use a battery powered one to run bolts in though, but never to apply any significant torque.

I think rust/corrorosion caused this issue, my truck is fairly rust-free, but this area seems to have been affected unfortunately.

 

I will probably go this route at some point in the future, I am also due for front suspension, so maybe I will tackle all of it at one time. I was going to go with the Bilstein 4600 and OME 2883 spring on the front. I just changed the rear shocks to 4600s a couple of months ago.

 

I did the Big Bang everything at once and you can, I’ll admit it was a bit much if you don’t have a 3rd vehicle.

You could easily break it up into pre refreshed knuckles and upper control arm bushings one day and then lower control arm bushings and struts/springs another.

you bought yourself some time to plan it which is great.