I need to replace the trailing arm bushings in my 78. I've never done this before. Some concern with shims. Any tricks/tips/advice I need to know?
Thanks in advance.

Mike

 

Start soaking in penetrant two weeks in advance. Including shock mount. I had more trouble with the shock mount than the TA bolts. Keep track of the shims as you remove them. Put them back exactly as they came out, specifically which side and how many and thickness. There are YouTube videos by Gary Vosberg that are excellent for removing TAs .

 

i tried soaking mine for days. hell, I used heat and still ended up cutting them off. keep a sawzall with long blades handy just in case. you might be ok if the car doesnt have much rust in that area.

 

Mike,
Do not sweat the shims...they more than likely going to change. It happens and that will be corrected when you get the rear aligned...WHICH YOU BETTER DO! This area is dealing with the toe of the alignment...and it is IMPORTANT. So if you think you are going to install new bushings and put shims in and be done...GUESS AGAIN.

I personally/professionally do not waste my time with penetrating oils. I jump right in and get the shims out....and if the bolts does not move..I cut it out....using a sawsall

AS for the lower shock bolt. I use the correct tool to aid in knocking it out. If I hit it two or three GOOD times and I can not see the bolt moving. I STOP. I remove the concentric bolt from UNDER the rear differential and take the strut rod with the trailing arm when I remove it from the car.

When the trailing arm is out of the car....I burn out the rubber for the strut rod bushing at the trailing arm end. This allows me to gain access to the INNER SLEEVE of the strut rod bushing that has SEIZED to the shaft of the lower shock bolt. I heat up the inner sleeve carefully and knock out the lower shock bolt. THE MAIN thing is not to beat the lower shock bolts so much that you actually snap an ear off your bearing support.

Chances are that the lower shock bolt is no good anyway due to very WEAK splines in the bolt that LOCK into the casting of your bearing housing. So I do not worry about trying to save it...95% of the time ..they are no good.

DUB

 

This is the same procedure I found worked with my 78

Also check the rear bearing end play while you have the trailing arms out. But this is good advise on how to proceed.

Once you remove the shims and loosen the pivot bolt and you still cannot move the bolt just cut them out. I spend 3-4 hours on the first TA until I have up and cut them out. The second TA came out in 30 minutes.

 

'Mikes c3'

If you are replacing the trailing arm bushing with the rubber design type. You are aware that it requires a special staking fixture tool to do this. And if you have this tool and put them in....BEFORE you do that....make sure that your trailing arm bolt will go through the inner sleeve that you will stake to keep the trailing arm bushings staked.

AND...when you have it staked an you take off the tool...MAKE SURE that you file or GRIND FLAT the crush sleeve that you just staked...because it will often time protrude PAST the large washer...and this needs to BE FLAT...so when you place a shim against the LARGE WASHER...it LAYS FLAT against this washer...and the inner crush sleeve is not causing the shim to lay flat. You might need to do BOTH sides.....LOOK at the factory ones...you will see what I mean

AND when you get that all done...NOW you can see there is NO WAY that the shims are going to work in the same spot...because there is NO WAY that you can perfectly reproduce what GM did when they staked the trailing arm bushing in originally.

IF you are installing the polyurethane design trailing arm bushing that you can do at home...just be aware that it is WIDER than the original..and if the trailing arm is 'tweaked'....due to the aftermarket polyurethane trailing arm bushing NOW being wider...you may run out of adjustment possibilities. DO NOT ask me HOW I KNOW this!

DUB