Common or Molded Rear Leaf Spring Bushings

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Shackle Bushings for Broncos and F-Series Trucks

The rear leaf spring shackles on the 80’s and 90’s Ford Broncos and F Series trucks can have different bushing styles and trying to find the right replacement for those bushings can be tricky. It is pretty easy to order what looks like the right replacement and is even labeled as fitting your vehicle but when it comes to actually installing the bushing you could find that they do not fit. This article will explain the differences and provide some help in finding a replacement that will work for your vehicle.

First off, there are two bushing positions on the rear leaf spring shackle – one connects to the leaf spring (rear upper) and one connects to the frame (rear lower). The bushing that could be molded or common is the one that connects the shackle to the frame or the “rear lower” position.

80-90 ford rear leaf spring shackle diagram

How to Tell the Difference

common or molded rear leaf spring bushing

The difference between molded and common shackle bushings is pretty simple:

  • Common Bushings have a metal shell around the rubber of the bushing and fit inside the spring eye
  • Molded Bushings are chemically bonded inside the spring eye – no metal shell

Identifying which kind of bushing you have can be difficult with the shackle connected to the frame, especially on trucks that have seen a lot of rough use, since the outer metal sleeve of a common bushing could be rusted or corroded to the shackle.

* If the bushing is just too destroyed, or missing altogether, buying a complete new shackle or measuring the dimensions of the spring eye itself (length, inner diameter, and bolt diameter) is going to be your best bet for finding a compatible replacement.

Getting a Closer Look

If replacing these bushings needs to be a one day job then you want to make sure you have the right replacements before going to the trouble of removing the bushing from the shackle completely. Sometimes the angle of the bracket combined with corrosion and rust makes it difficult to tell the type of shackle bushing on your vehicle at a glance.

To get a closer look chock the front wheels and jack up the rear of the vehicle until the rear suspension is unloaded. Then place jack stands under the frame and lower your vehicle onto the stands. Once the rear leaf springs are no longer under load you can use a socket to remove the bolt connecting the shackle to the frame. Once you have the shackle to frame bolt removed you should be able to rotate the shackle and get a better look at the bushing.

* Be sure you know the torque specs for the shackle bolt if you are not tackling the project yet and need to reinstall the shackle.


* 2019 F-150 4×4 Rear Shackle

Replacement Options

Once you have figured out what kind of bushing you have you want to select a replacement specific for that style of bushing with more confidence and get your vehicle back on the road quickly. There are three basic possibilities for shackle bushing replacements in these vehicles.

replacement shackle bushings 80-90 ford

* We should note that these replacements should be completed on both the driver and passenger sides to reduce the chance of future suspension problems.

  • Replacement Shackle with a Molded Bushing – If your vehicle has molded shackle bushings and you want a direct replacement you can find replacement shackles with the bushing molded in, like the originals. With this style replacement you will generally get a new shackle-to-spring bushing already installed in the shackle as well, which is convenient if that bushing is looking the worse for wear.
  • OE Style Common Bushing – If your shackle has a common bushing with a metal sleeve then that bushing can be removed and replaced. In this case the shackle and shackle-to-spring bushing can be reused saving some money, though the other bushings should be checked for wear or damage especially if they have not been replaced before.
  • Aftermarket Polyurethane Bushing – This is an option that is available for both shackle bushing styles. These bushings are free floating and held in place by the bolt alone so they do not need to be molded into the shackle or sleeved with a metal shell for installation. Poly bushings are also the most durable and long lasting option of the three though you sacrifice a little vibration damping for all that durability.

In Conclusion

The molded and common rear shackle bushings exist in a 15 year range of Ford F series trucks and Broncos and the only way to know for sure what you have is by looking. Hopefully you are now able to determine what you have and can make an informed choice about what replacement will work for your vehicle. If you are still unsure you can contact our customer service folks by phone or message.

If you want to DIY replace this bushing but do not have access to a press then check out our article about installing a bushing without a press.

To find replacement bushing kits or complete shackles for your vehicle check out

We hope this was helpful and from all of us at – Ride Smooth and Drive Hard.

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