001 Installing a bolt-in Heidts Rear Suspension Kit for a 1956 Ford F-100
Heidts’ four-bar rear suspension system for 1953-1956 Ford F-100s is almost entirely a bolt-on. The only welding required is to attach the axle and Panhard bar brackets. Scooter, the shop dog, supervised the entire installation between naps.

By Ron Ceridono – Photography by the Author

After installing some suspension components we’ve often heard our classic truck–building buddies sigh and say, “Well, if it was easy everyone would do it.” Recently we found something that came very close to fitting that description: Heidts’ 1953-1956 Ford F-100 bolt-in four bar rear suspension kits are so easy to install anyone with basic skills really can do it.

002 1956 Ford F-100 Suspension Upgrade from Heidts
The basic Heidts four-bar kit comes with frame and axle brackets, four adjustable bars, a new crossmember, and all the necessary hardware. We opted to include a Panhard bar and coilovers.

We install a new crossmember, coilovers, four-bars, Panhard bar, and all the necessary brackets and hardware–everything included in the Heidts rear suspension kit. For the most part this is a bolt-in kit, although some welding is required to attach the four-bar linkage brackets to the axle housing and the Panhard bar bracket to the frame. For those who don’t have the ability to weld, those chores can easily be farmed out after the bolt-in parts are in place.

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003 Old suspension bracket from the 1956 Ford F-100
With the rear leaf springs removed, the next task was to drill out the rivets holding the spring hangers to the frame.

One of the most time-consuming parts of installing this kit is the removal of the original components. Once the springs and shocks are gone, the four spring hangers and the original crossmember with the upper shock mounts have to be removed by taking out the factory rivets. While that can be challenging, we’ve found that a combination of grinding, drilling, and a big hammer gets the job done.

With the front spring hangers removed, the original holes are enlarged and the four-bar linkage brackets are bolted in place. The same holds true for the new crossmember that mounts the coilovers. Using the factory holes eliminates any possibility of positioning the brackets and crossmember incorrectly.

004 Ford F-100 Chassis bare before installing Heidts rear suspension kit
With the rear springs removed, the frame was leveled on jackstands (we used washers to shim the frame to make it so). We took this opportunity to measure the frame diagonally (left front corner to right rear and right front to left rear); it was within 1/16 inch.

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As we said some welding will be required to complete the installation of heidts rear suspension kit. In our case we rolled the rear end into place then approximated the correct pinion angle before welding on the axle brackets. Of course the threaded ends on the four-bar linkage provides the ability to dial in the pinion angle perfectly once the engine and transmission are in place, as well as making minor wheelbase adjustments to center the wheels in the fenders.

005 Drilling out chassis for Heidts rear suspension kit
After all four spring hangers were removed the holes were made larger with a 7/16-inch drill bit.

With the four-bars in place we boxed a short section of the frame to provide an attachment point for the Panhard bar bracket. On the axle end of the bar bolt-on brackets were supplied. Once in place the adjustable end on the Panhard bar allows the rearend to be centered precisely.

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Heidts has made installing a rear four-bar linkage system in a 1953-1956 F-100 quick, easy, and foolproof. Think of it as a four play for classic truck lovers.

006 New Upgrade Heidts rear suspension bracket for four bar linkage
The front four-bar brackets are marked left and right to avoid confusion. There are four bolts that attach each bracket to the side of the framerails.

Heidts Hot Rod & Muscle Car Parts
(800) 841-8188

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