Last week I changed my brake pads and rotors for the front of my 97 TJ. When I removed my driver side caliper, the lower caliper bolt was VERY loose and came out by hand. Uh oh. Looking at the bolt, it was painfully clear that the bolt and or knuckle were stripped. I tried the upper bolt and it did the same thing. So… stripped knuckle.

So I began the search to fix this problem, thinking I would need to replace the entire knuckle, which would be a LOT of work on the front end. I then found mrblaine. He told me about his new product that addresses this VERY common problem.

Due to the soft metal nature of the knuckle and the super small threads on the caliper bolts, this could happen easily enough and he’s built up a kit that addresses not one, not two, but all four caliper bolts, so I picked one up.

The kit is pictured above. Inside the kit was the above listed items.

To get started, all I had to do was remove the tire, caliper and rotor just as if this were part of a regular brake job. I’ll cover one side, but it is done to both.

The caliper mounting bolts will no longer be needed, so I got rid of em.

Hang the caliper out of the way using a coat hanger or something similar.

Once you have a good line to the caliper bolt holes, load up the provided drill bit into your trusty drill. If you have a weak battery powered one, I’d recommend a corded drill. I have a strong cordless drill and it worked wonderfully. This bit is VERY strong and eats through the metal quickly. I’d still recommend a full charge before starting though. Note, you do NOT need to coat the bit or the knuckle hole in oil. The sharp, strong bit and soft metal makes this unnecessary and will lead to issues later in the install process.

Drill the bit straight through the hole, pressing gently so as not to force the bit through to fast and have a rough cut. Be sure to not do this at an angle. New bolts will not fit if you do. :)

Once the holes are drilled, use the provided tap and thread these holes. I did this from the inside towards me so I’d be sure the thread inserts would go the way I wanted to.

Once the tap is all the way through, reverse it out slowly and carefully to make sure you don’t mess up the threads you just made.

At this point, the threads are ready to go in, but they need to be prepped a bit first. Before you install them, notice that they have a thin layer of oil on them to protect them. This oil needs to be removed for the loctite to function at its best. Take some brake cleaner and shoot them liberally. Let them air dry.

Once they have dried, take those stainless nuts that come with the kit and put them about halfway up the thread on the provided bolts. Take the thread inserts and thread them up the bolt, starting with the end that has the grooves for a screwdriver. It should look something like this:

See how deep those threads are? They’ll catch the metal of the knuckle MUCH better than the threads on the OEM bolt!

Now you can use the loctite and put a layer around the outer portion of those threads.

Now, thread them from the inside of the knuckle out towards the end of the hub. The bolt and nut will help you install the thread. Install it until the bolt stops against the knuckle. This will ensure the thread is flush. At this point, you have 2 options.
1. Leave the bolt installed and let the loctite cure overnight. This will give a strong bond.
2. Remove the bolt carefully and continue reattach the rotor, calipers, etc. The pressure from the caliper and bolt being on there should also help create a strong bond.

I did both - 1 on the driver side and 2 on the passenger side. We’ll see if there is any difference. I don’t think there will be. Anyway, with the thread installed, it should look something like this:

Reinstalled, everything should look normal. Make sure you torque the bolts down to OEM specs (about 11 lb/ft).

This kit is yet another excellent example of what mrblaine can put together. You have his Safety Thimble, Tough Stuff products, the Vanco Big Brakes, and now this (I’m sure there are others). I would HIGHLY recommend this kit to ANYBODY running stock knuckles. This stripping can happen at any time by anybody, professional or shade-tree mechanic.

-Paul

Just a quick note here from mrblaine on the install:

Very nice Paul. I appreciate the kind words. A few notes- Don’t worry as much about overtightening. Of course you shouldn’t, but the inserts are high quality and not as susceptible to stripping out as the softer cast iron the knuckle is made out of. You also have a bit more thread engagement to aid in preventing that as well.

If anyone else does this in steps as in one side and then later on does the other side and in the process loses the small tube of Loctite, don’t substitute any other kind. I did a lot of testing with various forms of threadlocker including the dry patch that came on the inserts and nothing works as well as the LIQUID Red 271.

I had to send the inserts back to EZ Lock to get their dry patch removed because of how inconsistent it was. Only 1 out of 4 would hold after the recommended 24 hour bond interval.

There is also an option of two different drill bits. The standard full shank and a reduced shank for those that don’t have access to larger than a 3/8″ drill motor.