Our Chevy 3600’s leaf spring suspension is in bad shape, but Davin isn’t bushed - Hagerty Media
The Redline Update 1950 Chevrolet 3600 is just hanging around the shop at this point. Quite literally, because the suspension was so walloped that putting the truck back on its wheels would have been just short of a death sentence. Leaf spring suspensions are simple in design, but when corrosion rears its ugly head, disassembly gets annoying—fast. The latest Redline Update shows how Davin dealt with this problem.
This Chevy continues to show that its previous life involved some hard work. Simply getting the rear suspension apart requires liberal usage of the oxyacetylene torch, using heat to break the bonds of rust that had fused together so many parts.
This all looks sweet in slow motion, but the fact of the matter is that cutting and disassembly are the easy parts. Once the rear suspension is apart, Davin finds that ready-to-install bushings are nowhere to be found for the shackles or leaf springs. Moments like these separate the enterprising gearheads from the parts replacers—Davin sets about making his own bushings.
He starts by taking a few measurements and then consulting the industrial supply site McMaster-Carr. There he finds bronze bushings which are really close to the right size. “Really close” proves to be workable; because Davin has access to the right tools to finish the fabrication, it’s more convenient to purchase the nearly perfect bushings rather than buy the bronze stock and spend an entire day at the lathe. With the “really close” bushings, he needs just one pass on the lathe to remove 0.010 inch from the outside diameter of one set before installation can begin.
The installation process has one extra step this time, though. Once the custom bushings are pressed into place, the inside diameter tightens up ever so slightly … just enough to prevent the pin from sliding through. No matter—there’s a tool for that too. A reamer removes material from a round recess in something, but it is not a drill bit. A drill bit punches a roughly correct diameter opening in solid stock; a reamer’s duty, on the other hand, is finishing a hole to an exacting diameter.
A quick pass with a reamer puts the bushings back in spec and allows Davin to quickly reassemble the rear suspension, making this truck one step closer to road ready.
There is still a lot more work to do, though, and more problems will inevitably crop up before Davin can hop in this truck for its first parts run. If you want to see how it gets back on the road, be sure to subscribe to the Hagerty YouTube channel to receive updates as each Redline Update goes live on Monday.