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Just Some Dude in Jersey
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Discussion Starter · #1 ·
If you don't like or don't want the harsher, sometimes squeaky, ride that polyurethane replacement bushings provide and want the softer ride of the oem rubber injection molded cartridge bushings, here's my experience getting them installed and some tips and tricks I learned along the way. If you envision yourself as a rally race car driver and want the more positive steering of the poly bushings or don't want to go through the difficult procedure to install the rubber cartridges, then by all means, read no further and just go with the polyurethane bushings. I have found that I REALLY like the oem rubber bushings, after 30 years and 200,000+ miles of having the poly bushings in my GT's.

The first time I did this was about 15 years ago and it stands as the hardest mechanical job I have ever done in my life. The Upper A-arm bushings were fairly straight forward and relatively easy to get out and somewhat easy to install with a vice, hammer, big washers, large sockets, etc.. It's the Lower A-arm bushings that are hard. The cast iron pivot that you have to suspend between the bushings prevents a simple pressing in of the new bushing cartridges. I had to do this procedure again this week on a new car and I started out like I did years ago and after 6 hours had only managed to get one in and the other halfway in on one Control arm. I still had the other Control arm to do. I asked for suggestions and looked on YouTube for advice. I found this video, which contained the key trick that made this job not so bad, and I was able to install the remaining 2 1/2 bushing cartridges in 2-3 hours.:


The GM control arms in the video are of a similar design as ours and the lower arm has that cast iron piece in the middle. The takeaways from this video that are of use to us:

1) Burn the rubber out of the cartridge shell, then use a hack saw to cut through the side of the shell so that you can collapse it.
2) Cut a piece of angle iron or pipe to fit between "arms" of the control arm to support them as you use a press, vice, hammer, etc. to get the bushings in. Shape the ends as necessary. It should be about 6" long. I used 1/8" x 1" piece of angle iron a hair over 6" long and it was the perfect size.
3) Use some lubricant. I used assembly lube. You could use some grease or oil if you want to.
Not in the video, but some other thing I did:
4) I tapered the leading edge of the cartridges with a grinder, so that they wouldn't snag and dig into the A-arm.
5) I also used a large file to round off and taper the sharp edge of the cartridge holes in the A-arms and slightly hogged out those holes a bit. I said "slightly".

I don't have a big ole hydraulic press, nor do I have a giant vice that can open 12 wide, nor do I have a giant c-clamp that can open to 12", so, for me, that meant that at some point I was going to have to start beating and pounding them in. I'm not going to go into all that, just use common sense and giant washers or giant sockets to spread out the force of your hammering. The bushings WILL skew and start going in cockeyed as they start going in. Take the time to try to correct this. Once they are about halfway in, the skewing will mostly stop. At first, I got them started going in by using some thick washers from the suspension, that were wider than the cartridge, and double the oem length 12.8 hardened bolts screwed into the cast iron pivot. This will hopefully get the cartridges started going in. But at some point early on, the "arms" of the Control arm will start bending inwards. Either right from the start or at this point, insert the 6" long piece of angle iron between the "arms". The angle iron is the critical trick that makes this whole operation doable. Continue tightening the bolts. As the cartridges eventually pass through the A-arm, the outer shell "MAY" or "WILL" start to hit your piece of angle iron. Adjust your piece of angle iron so that it doesn't interfere with the cartridge shell going in. At about this point you WILL start to encounter considerable resistance trying to tighten the bolts any further and you may risk snapping the bolts. Use good judgement and prudence and stop trying to use the bolts to squeeze the cartridges in. At this point you will likely have to pound the bushings in with a sledge hammer. It is essential that your piece of angle iron is in place at this point, the "arms" of the Control arms are very flimsy and bend easily.

I'm going to end my advice at this point, the rest is basic mechanics. Keep in mind that the method and the hammering are my own do-it-yourself ideas. At the time this morning when I was able to get them to go in without the whole process being a nightmare, the use of the 6" piece of angle iron to support the "arms" was an unproven method, by me. Now that I have been successful using that, I would now feel comfortable giving this job to a repair shop and have them press the bushings in. I DID NOT want to subject my excellent local repair shop to this ordeal and just hand them a bunch of A-arms and bushings and say "Here, put these in for me." They would probably charge me a fortune and I'd have to wait a week because they wouldn't really want to do this time consuming job. BUT, if I gave them all the stuff AND the 6" piece of angle iron, then all they would have to do is put it all in their press and it could all be done in an hour.

Pics of the angle iron in use and the successful install:

Bumper Gas Composite material Motor vehicle Engineering


Tool Gas Machine tool Engineering Automotive tire


Motor vehicle Hood Automotive tire Trunk Bumper


Pic of the easy to do Upper A-arm with cartridges installed:

Tool Bumper Household hardware Auto part Bicycle part
 

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Just Some Dude in Jersey
Joined
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16,409 Posts
Discussion Starter · #4 ·
FYI: DO NOT fully tighten the lower control arm pivot bolts until you have the front suspension in a fully assembled car with an engine. In other words, with the full normal weight of the car sitting on the suspension. This is the "neutral" weight position. Unlike the polyurethane bushings, which are free-floating/pivoting within the hollowed out oem cartridge housings, the rubber in the lower control arm rubber cartridges is bonded to the outer shell and inner sleeve. Tightening them in the "neutral" weight position assures that they aren't under twisting stress when parked, which over time could cause the rubber to tear loose from the metal.
 
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