Andrew has it right -- the spindle bases are different thicknesses to account for different width drums and offsets for rotors. The disc brake spindles are generally thicker at the mounting points than drum brake spindles due to rotor offset -- you'd think the opposite since discs have a 3/8" thick mounting bracket between the spindle and steering knuckle. This isn't much of a problem though. If the spindle is too thick a machine shop can grind them down on a surfacing machine. Don't try it at home -- the surfaces must all be exactly the same height and parallel. If the spindle base isn't thick enough you can get longer bolts and use grade 8 washers (they are hardened and won't crush) to space them out. How do you know if they are too thick or thin? Mount the new disc brake brackets and rotors, then see if the calipers will go on. Of course the pads need to be on the calipers. You should be able to easily see which way the rotor needs to move (in or out) for the caliper to slide on. Measure how far it needs to move and modify/space the spindle accordingly. If it just needs to move a very small amount -- under 1/16" -- you could grind one of the brake pads down to fit. That will take a little life off the pads, but shouldn't be a problem. ---------------- Date: Fri, 9 Dec 2011 11:27:53 -0500 (EST) From:adh@xxxxxxxxxxxxxxxxx (Sandwich Maker) To:amc-list@xxxxxxxxxxxx, Subject: Re: [AMC-list] Message-ID:<201112091627.pB9GRrl15607@xxxxxxxxxxxxxxxxx> " From: Vince Nitzvrnitz@xxxxxxxxxx " " " I have a 69 AMX with Bendix front brakes. Are the spindles with " bendix calipers the same as the spindles with Kelsey Hayes Calipers? " I want to use a set of wildwood brakes but they say only cars fitted " with the OEM Kelsey Hayes calipers. i don't know for sure; amc had a lot of spindle p/n and i know at least some of it was differences in the mounting flange thickness, but they all, disk and drum alike, used the same bearing sets [except for the '75-8 bendix setups, which used a different pair]. i would not be surprised if the wilwood kit would fit all amcs except for '75-8 with perhaps only a little work. -- Frank Swygert Publisher, "American Motors Cars" Magazine (AMC) For all AMC enthusiasts http://www.amc-mag.com (free download available!) _______________________________________________ AMC-list mailing list AMC-list@xxxxxxxxxxxxxxxxx http://list.amc-list.com/listinfo.cgi/amc-list-amc-list.com