Words & Photos: John Gunnell
When the Camaro arrived in 1967, one of the selling features Chevy hyped was a rear mono-leaf spring suspension. A single-leaf spring system cannot be as strong and durable as a multi-leaf one. Over time it will weaken or break, causing problems ranging from bottoming out to complete loss of control.
In 1968, Chevy switched to staggered shocks to improve the mono-leaf suspension. This helped, but those cars are now over 50 years old and suspension problems are common. The springs weaken or break, the frame mounts at the front of the springs deteriorate and the shackles at the rear do, too – just take a look at the photo above, which shows a weak and rusty OEM mono-leaf spring and worn forward frame mounting bracket.
John Diermeier of John’s Custom Auto in Manawa, Wis. was restoring a 1968 Camaro convertible and the owner complained it was bottoming out. It turned out the car had all three of the problems mentioned above.
Close-up of OEM frame bracket with damaged and worn rubber bushing.
The front end of the rear spring was only wedged into the front frame bracket with nothing holding it. The spring itself was rusty and weak. Using Internet sites for Camaro buffs, John discovered that many reproduction mono-leaf springs available today don’t meet the OEM specifications. He also noticed the shackles were shot and found out that improved shackles are available.
After doing this research, Diermeier decided to convert the Camaro to four-leaf springs using a conversion kit made by Eaton Detroit Spring (www.eatondetroitspring.com). “They knew the problem and how to fix it,” Diermeier said. “They made springs for the car and I had them in my hands in a couple of days. They were pricier than other springs, but they were awesome.”
This is a close-up of the new shackle with red polyurethane bushings.
The brackets that attach the springs to the frame at the front were sourced from Classic Industries (www.classicindustries.com). These came with the bushings pressed in. Diermeier torched a little metal off the sides of the brackets. “Even the rusty factory brackets didn’t fit just right,” Diermeier said. “I bought all new hardware, too, and I would recommend that for anyone doing this job.”
Classic Industries front bracket comes with rubber bushings installed.
Because the four-leaf spring use a center-bolt to hold the leaves together and the axle spring seat does not have a hole to accept the head of the bolt, the top OEM rubber axle pad has to be replaced with a steel “spacer.” The bottom axle pad is still used. Since a four-leaf spring is thicker that a mono-leaf, there will be a gap between the shock plate and top spring seat, but this is no problem.
The gap caused by use of a spacer is not a problem.
At the rear, Diermeier used Classic Industries’ 32135R-1967-1981 Camaro Multi-Leaf Shackle Set with Red Polyurethane Shackle Bushings from Classic Industries. It’s designed to reduce wheel hop upon acceleration, prevent shuddering while braking and deliver better handling control. The $82 kit includes shackle plates, shackle bushings, shackle bushing sleeves and shackle bolts.
Here are the new four-leaf springs installed on the car.
The Camaro convertible now has multi-leaf springs that are stronger and more durable than the original mono-leafs. The Camaro’s owner prefers safety over 100 percent originality, so the car is now set up for a better and safer ride.