J Body Control Arm Refresh.

Since I’ve done this a few times now, I thought I’d share my experiences with freshening up the Sunbird’s control arms this time around.

Ball joint removal:
If they’ve never been replaced, you unfortunately are going to have to get the factory ball joint rivets out first. You can either attempt to drill them out, or grind the heads and press or pound them out. Each method has its difficulties.

For drilling, one side of the rivets has a center indentation to start the drill. At this age, they may no longer provide a good center to drill anymore due to rust etc. The other tricky part will be setting the control arm up to get a straight hole, since they are not exactly flat on the opposite side. One more thing about this method is, I wouldn’t advise using a .500(1/2)” drill as others do – the hole is actually closer to .453(29/64)” and you want to minimize material loss which may weaken the mounting points. If your hole is not dead center, you’ll want to go smaller still. Only drill out enough just to get it out, and make sure your hole is as centered and as straight as possible and you will be ok. The bolts that replace the rivets are 12mm in the kit I got, so you may have to drill out the hole a bit to fit them, but that is better than blowing the hole out too large and probably also changing its location when trying to get out the rivets.

To be able to press out the rivets, you’re going to have to use a cutoff or grinding wheel to get the head off at least one side of the rivets. The heads on the lower side are shallower than the top side, so to make it a little easier, grind them off. You may want to try to grind the head a little below the surface of the arm if you can, while trying to avoid grinding the arm. Any lip remaining will make it hard to press out, especially if you are going to try to hammer it out. With a hydraulic press, it is not quite as big a deal, it will just fold the small amount of lip over as it goes.  Pressing them out can mushroom the mounting holes in the control arm a bit on the far side. I would suggest you put in some ball joints (new, old, or .281(9/32)” thick material) and vice, C clamp, or hammer them carefully back to flat before putting things back together.

Bushing removal:
You can burn bushings out with a torch, but I don’t find it necessary due to their design in this case. They are somewhat hourglass shaped, so they don’t contact the entire inside of the arm, making them a little easier to get out because they fuse to the arm in fewer places. If you do want to torch them though, I’d keep the heat toward the center of the bushing or the steel bolt tube; these aren’t the most rugged of control arms, and you could probably distort or melt the stamped metal pretty easily. Another word of caution when doing this, and I have a feeling this is pretty rare, but somehow I had one of them build up pressure once and shoot the center tube right out of the bushing. (It wasn’t a J control arm.)

I found on my factory 128k mile control arms that all that had to be done for 3 out of 4 was hacksaw one side of the rubber bushing flange around the outside edge to weaken it enough so it would fold up when I pounded them out the other side of the housing. You also can hack the whole “rubber flange” part off if you like. On the fourth, I had to resort to drilling some holes in the rubber to weaken it and loosen the rubber’s hold.  Just be careful of chewing up the inside of the control arm housing when doing this, the drill wants to walk. Also, when this happens, it may leave some rubber behind in the bore which you will have to find a way to scrape out before installing the new bushings.

Installing the new bushings and ball joints is pretty straight forward. The ball joints simply bolt in with three new bolts (usually supplied with the ball joints,) and the bushings you should be able to push or tap in easily after you’ve greased them, assuming you’re upgrading to polyurethane while you’re in there – which you should, and you won’t have to do this again for a long time, and will also improve handling while you’re at it.

The only other thing of note when going to install the control arm and spindle, is just as you may have already found if you’ve taken them out, it may be easier to install them as a unit. Once the driveshaft enters the picture, there is no room to install the castellated nut on the ball joint, or any way to torque it either.

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