1978 Ford Bronco Suspension Parts: Shackle Flips Guide

If you own a 1978 Ford Bronco and want to improve off-road performance, a shackle flip is one of the most effective suspension upgrades. This modification relocates the rear shackle mount to increase lift, improve articulation, and reduce spring wrap. But choosing the right parts and understanding the process can be tricky. This guide covers everything you need to know about 1978 Ford Bronco shackle flips, from what parts are required to how they change your rig's behavior.

What Is a Shackle Flip and Why Do It?

A shackle flip reverses the orientation of the rear leaf spring shackle. On a stock Bronco, the shackle is attached to the frame at the top and hangs down, connecting to the spring. In a flip, you mount the shackle beneath the frame, so it hangs below instead. This does two things: it lifts the rear of the vehicle (typically 2-3 inches) and allows the spring to droop more, improving axle articulation. It also transfers some weight to the front of the spring, reducing axle wrap under acceleration.

For a 1978 Bronco, this is a popular way to level the truck after a front lift or to add extra clearance without installing a full lift kit. It also keeps the ride quality relatively mild compared to add-a-leafs or blocks.

Key Components for a 1978 Ford Bronco Shackle Flip

To perform a shackle flip, you'll need several suspension parts. Depending on the brand, they may come as a complete kit or you can source them individually.

1. Shackle Flip Brackets

These are the core of the upgrade. They are heavy-duty steel plates that bolt to the frame and relocate the shackle hanger from the top to the bottom of the frame rail. Look for brackets made from at least 3/16-inch steel with a corrosion-resistant finish. Popular options include kits from Tuff Country, Skyjacker, and Deaver. Ensure they are specifically designed for 1978-1979 Ford Broncos (the 1978 and 1979 models share the same suspension layout).

2. New Shackles

Many shackle flip kits include longer or strengthened shackles. Stock shackles are often weak and may not be long enough for proper geometry. Aftermarket shackles are usually thicker and have a greaseable bolt, which prolongs bushing life. Some kits use a “zero-rate” shackle that doesn't change the spring angle but provides a different mount point. Others include slotted shackles that allow fine-tuning of ride height.

3. Lift Springs or Blocks

A shackle flip alone typically gives 2-3 inches of rear lift. If you want more, you can combine it with new leaf springs or a block. However, blocks can reduce stability and are not recommended for serious off-roading. Aftermarket leaf springs from brands like Deaver or Alcan can provide a softer ride and more lift. If you keep stock springs, you may need to add a leaf or use a shim to correct pinion angle.

4. U-Bolts and Hardware

You'll need longer U-bolts to accommodate the added lift and thicker axle pads. Many shackle flip kits include new U-bolts, but if not, measure your axle tube diameter and spring pack thickness. Also get new bolts, lock washers, and perhaps Grade 8 hardware for safety. Never reuse stock U-bolts after a lift.

5. Shocks

Longer shocks are almost always required after a shackle flip. The increased droop will exceed the stock shock's travel limit, leading to damage. Measure your shock length at full drop and compression to choose the right pair. For a mild lift, consider Rancho RS5000X or Bilstein 5100 series. If you plan on serious off-roading, go with a reservoir shock for better heat dissipation.

Installation Overview

Before starting, raise the rear of the Bronco on jack stands, remove wheels, and support the axle with a second set of stands. The process involves removing the old shackle hanger, cutting or grinding off the rivets if it's factory riveted, and bolting in the new flip bracket. You may need to drill new holes in the frame. Then attach the shackle to the bracket and the spring. Adjust the pinion angle with shims if needed. Finally, install longer shocks and torque everything to specs.

Tools Needed

• Angle grinder with cutting wheel
• Drill with cobalt bits
• Socket set and torque wrench
• Jack and two sets of jack stands
• Penetrating oil for rusty bolts

Common Challenges

• Rivets: Factory shackle hangers are riveted; you'll need to grind off the heads and punch them out.
• Frame clearance: In some cases, the new bracket may interfere with the exhaust or gas tank skid plate. Check clearance before finalizing.
• Pinion angle: Adding lift changes the rear driveshaft angle. Use shims (or adjustable upper control arms if you have a four-link rear, but 1978 Broncos are leaf spring) to reduce vibration.

Pros and Cons of a Shackle Flip

Pros:

• Adds 2-3 inches of lift without a full spring replacement.
• Improves articulation for rock crawling.
• Reduces axle wrap, which can destroy leaf springs.
• Relatively easy DIY project.

Cons:

• Rear lift can cause the vehicle to sit “stinkbug” (front lower than rear). You may need a front lift to match.
• Excessive lift can cause driveline vibrations.
• Bracket quality varies; cheap kits may bend or crack.

Recommendations for a 1978 Bronco Shackle Flip Build

For daily driving and light off-roading, a complete kit from Tuff Country (ESK-1100 series) or Skyjacker ($150-200) is a solid choice. They include brackets, shackles, bushings, and hardware. Pair with a set of Bilstein 5100 shocks (near $100 each) and new U-bolts. If you already have aftermarket springs, you can just buy the shackle flip brackets alone from RuffStuff Specialties ($120) and use your existing springs.

For heavy off-road use, consider Deaver springs (around $400 per pair) with a Deaver shackle flip. This combo offers plush flex and long life. Expect to spend $600-800 total.

Final Verdict

A shackle flip is one of the best bang-for-your-buck upgrades for a 1978 Ford Bronco. It cleans up the rear suspension, provides useful lift, and enhances off-road capability. Stick with name-brand parts, take time to set pinion angle correctly, and upgrade your shocks. With proper installation, your Bronco will handle rough trails much better without sacrificing street manners.