GM 10 & 12 Bolt Bolt-On Rear Disc Brake Kit

• Bolt on rear disc brake kit for 10 and 12-bolt rear axles with no welding required
• Substantial performance upgrade over stock drum brakes
• Fits GM 10 and 12 bolt rear ends in midsize cars. Will not fit full size cars, pickups, 7.5" 10 bolt axles, or applications with staggered shocks
• Includes two bolt-on caliper brackets, two vented rotors, two new GM metric calipers with or without emergency brake, pads, and hardware
• Rotors have both 5 on 4-1/2" and 5 on 4-3/4" to accommodate a variety of wheels
• Fits axle with a maximum flange diameter of 6-1/4" OD and brake register size of 2.78" or smaller

Rear Disc Brakes for Performance and Safety

We tend to look back at the muscle car era of the 60’s and 70’s through rose-colored glasses. Everybody remembers lumpy solid lifter camshafts, big compression ratios, and blinding straight-line acceleration. But in the six decades or so that have passed since those big block-powered dinosaurs ruled the roads, we’ve gotten used to some modern performance and safety features that become conspicuous in their absence when we jump in the old Chevelle or Camaro for a trip across town. Those drum brakes that were just fine in 1969 can lead to some panic inducing near misses in modern traffic. To add some performance and peace of mind, don’t drop the bucks on a rebuild of those archaic rear drum brakes. Instead, consider a bolt-on rear disc brake conversion that won’t cost much more than a drum brake refresh, but will add some serious performance and safety to your GM midsize or ponycar.

Complete Bolt-On Rear Disc Brake Kit

Back in the day, only factory hot rods like the Z/28 were fitted with rear discs. The rest of the herd was saddled with heavy, fading rear drums. This Speedway Motors GM 10 & 12 Bolt Bolt-On Rear Disc Brake Kit makes it easy to bolt up the brake setup that was a trick high performance option when your GM midsize muscle car rolled off the line. This kit comes with everything needed to bolt GM Metric calipers on your 10 or 12-bolt GM rearend housing with no welding required. The caliper brackets in this kit simply bolt-on to the housing flange, making the install an afternoon job, not a full-on fabrication project.  You can choose calipers with or without an emergency brake and the calipers come complete with brake pads and slide bolts. This kit also comes with a pair of vented 11-1/4” rotors. There may be bigger and more expensive rear disc brake kits out there, but this one delivers impressive performance at an affordable price while still looking more trick than those rusty old drums when viewed through big-inch Pro Touring-style wheels.

Note that GM made many variants of the venerable 10 and 12-bolt rear. The brackets in this kit are configured to fit housings that do NOT have staggered shocks. There’s a full list of applications below, but typically, you’re going to find these in midsize cars like Chevelle and Cutlass from ’64 into the 70’s as well as first-gen Camaros and many years of Chevy II/Nova.

This kit is designed to fit 10 & 12 Bolt rear ends from:

• 1964-77 Buick Skylark
• 1964-73 Chevy Chevelle
• 1964-79 Chevy Nova/Chevy II
• 1964-77 Chevy El Camino
• 1967-69 Camaro
• 1970-77 Chevy Monte Carlo
• 1964-71 Oldsmobile 442
• 1964-77 Oldsmobile Cutlass
• 1964-73 Pontiac GTO
• 1964-77 Pontiac LeMans
• 1964-70 Pontiac Tempest

This kit is NOT designed to fit the following:

• 12-bolt truck rearends. (For truck applications, see 136159 Speedway 63-70 GM C10 Rear 6 Lug Disc Brake Kit or 136163 Speedway 63-70 GM C10 Rear 5 Lug Disc Brake Kit)
• The later 7.5” 10-bolt (For 7.5” axles, check out 91031928 GM 7.5 Inch 10 Bolt Bolt-On Rear Brake Kit w/ E-Brake)
• 10 and 12-bolts in fullsize cars like the Caprice, Bel Air, and Impala. (For full-size rear disc kit, see 916645634 Speedway Rear Disc Brake Standard Kit, 55-68 Impala)
• 10 and 12-bolts with staggered shocks. (If your car is so equipped, our 916645629 Staggered Rear Disc Brake Kit, GM F/X Body, 10 & 12 Bolt is for you)

 To verify that this kit will work on your axle, you can double check that the flange where the caliper bracket will bolt up has the following dimensions:

• 3-1/8" center-to-center distance for the top two bolt holes
• 2-11/16" center-to-center distance for the bottom two bolt holes
• 2-7/16" distance from the center of the top bolt to the center of the bottom bolt

Also check that the axle flange where the lug studs are pressed on has an outside diameter that is no larger than 6-1/4” and a brake register (the raised part at the center) that is no larger than 2.78".

91031919 Instructions (PDF)

Axle Flange Identification Chart (GIF)