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| C4 Corvette Chassis |
| 1957 Corvette RestoMod Project - Page 6 Front Bushings and Ball Joints The front-end bushing and ball joint upgrade continues. First order of business is to remove all control arm bushings. I plan to replace these black rubber pieces with new polyurethane red bushings from Energy Suspension. Rubber is nice but PU is better. Polyurethane produces a stiffer ride due to the strength of these pieces, but they also last much longer. Rubber is susceptible to road and weather damage. To see this, look at your bushings, and if they are cracked or breaking off, time to replace them. Chapter 5 of my book goes into detail on how exactly I removed the bushings. I hope to have the completed book on building a complete chassis out in just a few months; however, individual early chapters are now available from the bookstore! The upper control arm ball joints are also included on this page. |
| Picture above left is the front assembly cradle, seen upside down. You can see the upper control arms have not been removed yet. But, the spring is out and lower controls are out as well. Above right is a puller tool set that will make disassembly of the front and rear ends much easier. This one is made by PowerBuilt and really helped me with this job - cost, about $130. |
| The task of removing front-end control arm bushings and ball joints is complicated by the control arm's material. The C4 Corvette has cast aluminum control arms, which are very strong and light weight, but aluminum is not as tough as steel. I had to be very careful not to damage the arms in any way. The process is complicated because to press out the bushings and old ball joints takes a lot of force. And without a machine press, the job needs to be well thought out before beginning. BE CAREFUL! |
| At left, the upper ball joint is riveted to the control arm from the factory. You can also see a pilot hole drilled into one of the rivets. Also seen is the grease fitting in the middle. Once all the rivets are drilled out (no easy task I might add), you can see the old rivets, the removed ball joint, and the control arm opening. Be very careful not to drill at an angle, otherwise the soft aluminum control arm will be damaged. |
| The upper control arm is smaller than the lower control arm. This contributes to the incredible handling of the C4 Corvette suspension system. Many of these C4's have been used for autocross competitions due to their excellent cornering characteristics. Combined with the high-torque ability of the LT-1 engine, the C4 platform was a tough car to beat. Autocross is like a miniature version of road racing. Cones are used in a "parking lot" setup of the course and tight turns are the norm. Next, I tackled the removal of upper control arm bushings. Read on... |
| Picture left is one of the upper control arms. My plan was to remove the bushings and pivot bar by pushing the bar and bushings through the eyelets of the arm. Please note, the force needed to press the bushings out of the eyelets is high. This force will probably bend the arms out of shape, again because they are aluminum. So I came up with a jig on my well-worn B&D Workmate. The jig would secure the arm and allow sufficient force to be applied to press out the pivot bar and bushings. |
| If you want to know how I built my upper control arm jig, see Chapter 5 of my new book - sorry, I can't give away all my secrets here! The pressing out of the pivot bar and bushings is done by forcing the left end of the bar (as pictured above) through the left eyelet. This moves the inside washer of the right eyelet to the right. This washer is smaller than all other bushing washers in the control arm. And it's small enough to fit inside the right eyelet. Again, a lot of force is required to push both bushings. I tried to secure the upper ends of the "Y" of the control arm, but this proved insufficient in preventing possible damage. The "Y" arms started to bend too much. My final solution for this was easily accomplished using materials around my garage - materials that I'm sure you have as well! |
| Pictured right, the front and rear bushings have been removed from the upper control arm and pivot bar. Notice the outer end of the rear bushing and inner end of the front bushing have been torn away. I did this so that extra material did not have to be forced through the eyelets too. It was hard enough just pushing the bushing - I didn't want the "outside" bushing material squeezed through the eyelet as well. |
| The lower control arm bushings and eyelets are pictured left. The top picture is of the bushing before extraction. The bottom picture is after. A press is perfect for removing lower control arm bushings, if I had one. The puller tool shown at the top of this page was worthy enough to get the job done. The bushings didn't go down without a good fight though. One thing to always keep in mind and be cautious of is damaging the control arm. Always be aware of how your tools make contact with the arms. And ALWAYS test your method first and watch to see if the arm's shape integrity is being altered or compromised. |
| Well, the upper and lower control arm bushings are successfully extracted - whew! And, the upper ball joints have had their rivets drilled, punched out, and the ball joints literally fell out of the upper control arm. But what about the lower ball joints, you know, the ones in the larger lower control arm? Good question! I tried the same puller tool I used before to push the lower ball joints out - no luck. No ladies and gentlemen, this extraction is going to take more force than I have in my little garage. |
1957 Corvette RestoMod