What Size Bolts Are Needed To Install Caliper Mount Bracket For Kodiak Disc Brake Kit K2HR79E?

Question:

I have a 2010 Heartland Bighorn 3055RL with Lippert 6,000 axles and 8 on 6.5inch 9/16inch lugs with 16inch wheels. Axle part number is 30817. I ordered the K2HR79E kit 7K lb primarily due to the 8 on 6.5inch lug pattern and 16inch wheels. Watching the installation video, it was recommended that you knock out the brake flange bolts and replace them with 1/2inch x 1 1/2inch bolts due to the thickness of the caliper bracket. While waiting for delivery Ive pulled one electric brake hub off to check that the spindle measurements matched the #42 spindle bearing and seal measurements, and they do. However, I noticed that I do not have 1/2inch studs in the brake flange. They are 3/8inch as are the holes in the flange. Am I correct in assuming I will need to open the 3/8inch holes to 1/2inch and use the longer 1 1/2inch bolts? If so, it appears that bolt heads, washers, and nuts are going to interfere slightly with the swelling where the flange meets the axle which would require a bit of grinding to provide clearance. Am I missing something? Was this the correct kit to order or is there one with 8 on 6.5inch lug patterns and 3/8inch brake flange bolts? I didnt think it would be appropriate to just use longer 3/8inch bolts if the holes in the caliper bracket are 1/2. Help. Also what is the diameter in the hole of the bracket that goes over the spindle?

asked by: Ronald M

Helpful Expert Reply:

I had our warehouse measure the diameter of the mounting bolt holes in the caliper mounting bracket included with the Kodiak Disc Brake Kit - 13" Hub/Rotor - 8 on 6-1/2 - E-Coat - 7,000 lbs # K2HR79E you were looking at, and you will need 3/8" x 1-1/2" bolts instead of 1/2" x 1-1/2" bolts.

I also had them measure the center hole of the bracket and it measures 3.244" as you can see in the included diagram.

I included a video of the # K2HR79E for you to take a look at.

expert reply by: Samuel C