1961-1978 F-100 Bolt-In S-550 Mustang Rear Mounting Kit

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  • Regular price $795.00

This kit is designed to allow the S-550 suspension to bolt to a F-100  (34" wide frame) using the factory subframe mounts on the 2014-2023 Mustang S-550 rear suspension. It also integrates mounts for a 12” coil-over. This setup allows for an unmodified bed and much lower than stock ride height, as well as modern, brakes, suspension, and a limited slip differential. The kit uses the leaf spring bracket holes to locate the assembly (be careful not to mangle the holes when you are removing the factory rivets!) and bolts to the side and bottom of the frame rails.  A small notch in the bottom flange of the frame rail is the only cutting you need to do (to clear the upper arm). You will need to drill some holes for installation, but the brackets act as templates to keep the install simple and straight forward.

Kit contains all mounting brackets and hardware required to mount the 2014-2023 Mustang S-550 rear subframe to your F-100 frame. Coilovers not included in kit. 


Current Lead time is 2 weeks.


Install Overview:

Install this kit by first removing the old suspension, including the leaf spring hangers. Then bolt in the front brackets using 2 of the leaf spring hanger bolt holes. At this point, bolt on the s-550 suspension to the front mounts, and mark & notch the bottom flange of the frame as required. Install the rear brackets to the s-550 subframe and clamp them tight against the bottom and side of the frame rails.  Drill and install bolts to hold it in place, then remove the subframe to allow you to finish drilling and bolting the brackets in.

A machined shock adapter is provided for the lower arm to allow a standard coil-over to bolt in place. A bracket is also included to slide the sway bar backwards if needed to clear your coil-over. The kit is designed to fit a 12” coil over (~12” eye to eye at ride height). We recommend a 350-400 lbs./in spring. Please note, coilovers are not included. 

 Enjoy your modern suspension, brakes, and limited slip!


Driveshaft Tip - You can get a standard yoke that fits the mustang diff (Ford P/N: F8TZ4851BA). This takes a standard 1350 U-joint and makes getting a driveshaft much easier.