With vintage muscle cars being 35-plus years old, it won't be uncommon to find the factory rubber body bushings dried out and in need of replacement. As the bushings degrade, the body will slowly sink and the panel gaps will start to change. You could replace the worn components with rubber during your restoration, but those will eventually dry out as well. Luckily there is another option that will outlast rubber and also stiffen the chassis for better handling capabilities. We are talking about a polygraphite body mount kit from Performance Suspension Technology (PST). These bushings are stiffer and less likely to be eaten away by things like Father Time, oil, and road salt. If stiffer is better, then why not just solid mount the body to the frame? Because the bushings not only cushion the body, but also isolate road noise and vibration. A solid mount will transfer all that nastiness right into your interior. Plus, there has to be some sort of give or things could start to crack or even break. The PST bushings have a good balance of firmness and give, and handling is improved without things getting too loud or damaged. With these components being under the car and exposed to a pretty harsh environment, the hardware could also be on its way out. This was the case for the '66 Chevelle we have been tinkering with. Not only were most of the bolts flat out missing, the few that we did have were rusty. We picked up a new hardware kit from Original Parts Group (OPG) instead of trying to guess what we needed and hoping the hardware store had any. The kit came with the proper bolts and washers needed for the job, but we ended up using the washers from the PST kit. All the parts set us back a little over a 120 bucks and the job took an afternoon to complete. part number 3-4111, $99, comes with all the proper sized and shaped polygraphite bushings, inserts and flat washers. The hardware kit,part number 3-4111, $99, comes with all the proper sized and shaped polygraphite bushings, Here is the stuff we picked up from PST and from OPG. The PST kit, PN 514MH, $26.95, from OPG, came with the right 7/16-14 bolts and flat washers. Since we had duplicate washers we decided to go with the gold cad plated ones from PST.Here is the stuff we picked up from PST and from OPG. The PST kit, PN 514MH, $26.95, from There are five different sized bushings that go in different location on the frame. PST clearly numbers the bushings, which correlates to their appropriate location on the instruction sheet.There are five different sized bushings that go in different location on the frame. PST cl This is how the bushings will be configured, except at the core support. Starting from the bottom it will go washer, bushing, frame, bushing, and washer. The steel insert will run through the middle along with the bolt.This is how the bushings will be configured, except at the core support. Starting from the To start the job, all the factory hardware needs to be remove or loosened. Remove all the bolts from the side you will work on first and just loosen the other side. This will keep the body from shifting, but still allow it to articulate enough to change out one side. Don't forget the core support bolts that are hiding under the radiator. You may not have to remove the radiator fully just unbolt the top and see if you can shift the radiator around enough to slip the bolts out.To start the job, all the factory hardware needs to be remove or loosened. Remove all the It won't take much to separate the body and frame enough to slip out the bushings. We found a jack with the pad removed and a section of 2x6 worked just fine. If your car has a shiny paint job, then you'll want to pad the wood with some soft rags. Also, jack up the body very slowly and keep an eye on anything that runs from the frame to the body like fuel and brake lines. If they are binding, you will have to unhook one side of the lines for this job.It won't take much to separate the body and frame enough to slip out the bushings. We foun The car we are working on is just a shell so we didn't have a radiator to contend with, making the core support bushing much easier to change. The configuration of the core support bushings is basically inverted from the rest of the bushings on the frame. Bushing number 4052, with the steel insert already slipped in the middle, goes in between the frame and core support.The car we are working on is just a shell so we didn't have a radiator to contend with, ma Bushing number 4072 goes on top. The steel insert will hold the two bushings together enough that you won't have to hang on to it.Bushing number 4072 goes on top. The steel insert will hold the two bushings together enou Washers are placed above and below, followed by the new bolt. Once the rest of the bushings are in place and the body is lowered back down, the lock washer and nut can be installed.Washers are placed above and below, followed by the new bolt. Once the rest of the bushing For the rest of the bushings the hardware will come up from the bottom and screw into a nut plate in the body. It is highly recommended that you run a 7/16-14 tap through the nut plate to clean up the threads. If you strip the threads or break a bolt, you will have a lot of time invested in cutting open the sheetmetal to change the nut plate.For the rest of the bushings the hardware will come up from the bottom and screw into a nu After tapping all the nut plates on one side, bushing number 4049 was set on the frame along with a washer in each location, except for the one right behind the trans crossmember. Bushing 4050 with another washer and bolt will slip in from underneath.After tapping all the nut plates on one side, bushing number 4049 was set on the frame alo The only other oddball bushing is located right behind the transmission mount. This location has a different nut plate in the body so it uses bushing 4072 on top and bushing 4073 on bottom. There is also a different washer that goes on top that has a larger hole in the center to allow that nut plate to pass through.The only other oddball bushing is located right behind the transmission mount. This locati After all the upper bushings and washers were in place, the body was lowered back down and bolts threaded in. Some of the washers may move a bit, making the bolts a little hard to start, but raising the jack up just a hair should allow the washer to move enough to get the bolt in. Get all the bolts started before removing the jack completely and tightening them up-and don't forget the core support.After all the upper bushings and washers were in place, the body was lowered back down and By Calin Head Enjoyed this Post? Subscribe to our RSS Feed, or use your favorite social media to recommend us to friends and colleagues!
