We’re back with our Cadillac Coupe de Ville. This vehicle came in with the goal of fitting a 28-inch wheel, which means pretty extensive suspension modifications.
In this case, the factory front suspension is a double wishbone, meaning there are physically pairs of arms on either side of the vehicle that move up and down at the same time as each other. In this case, we have a lower control arm which mounts to the frame of the vehicle and can pivot up and down. And then we have our factory upper control arm, which would normally rest right here to hold the upper portion of the suspension. Because this is a boxed piece of steel, it doesn’t allow for a lot of motion. Additionally, because of the bushing housings that are in it, there’s very little thickness where they attach, meaning this is a pretty weak component. So we’re t’ throw it away.
The new ones that we custom made for the vehicle are made out of 1 ½-inch tubular steel, quarter-inch wall chrome-moly, the same stuff roll cages in NASCAR vehicles are comprised of. Additionally, we were able to use a factory 6184 bushing that is 2 inches wide on either end of the arm, rather than the factory half-inch wide bushing, giving us four times the surface area contact to ensure strength and rigidity of the suspension. Last but not least, we bolted these together with a standard half-ton Chevy pickup ball joint that bolts directly into the control arm. Long gone are the 30-year-old design of pressing a joint, pressing in a part, buying an arm every time the suspension needs a repair. With the way we built the suspension, 10 years from now, if it needs a ball joint replacement, he can simply buy a $30 part off the shelf rather than find some specialty shop to custom make something else again or try and track down a 40-, 50-plus-year-old part. Not only does this give us strength, but reliability and consistency of use.
Now the reason that we did this on this vehicle is to gain more suspension travel.
Because the owner wants to fit a larger wheel, we need to push the suspension downward to create more room in the wheel well. By using a tubular control arm that is physically twisted 90 degrees down, we’re able to lower the entire knuckle of the vehicle almost 6 inches from its factory position. What that means is, rather than sitting tucked up high, we’ll physically move the suspension down without affecting the range of motion. So even though it still moved with 6 to 8 inches of travel before, we have effectively lowered the suspension out of the vehicle without modifying its range of motion. The owner will still be able to drive it over speed bumps, still be able to hit potholes, and it will still drive down the freeway like it did from the factory.
If you’ve got a resto, a donk, a lowered or slammed vehicle, or one lifted to the sky, and you’re having suspension issues, or you just want to make sure that it gets done once and done right, please let us help. We’re more than happy to take the time at no cost to sit down with you and spend a few hours going through a game plan for your vehicle, start to finish.