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Discussion Starter #1
Had a couple hours this afternoon in the shop while the hired hand was changing oil in the truck, hehe. (benefits of bossing.) So I grabbed the 'front end' with the forklift and hauled it to the shop and removed the upper A arms. Then I disassembled them per instructions in the "Mustang Restoration Handbook" by HP Books. It took a 1-1/4" box end wrench with a cheater extension to remove the bushings and pivot shaft, but they came off with no problem. ( Man, were the rubbers inside all worn! ) A vice to hold the A arm works really well. Then it was easy to remove the ball joints and spring perches. One perch had seen better days.

All in all, the A arms are in excellent shape and I'll blast and paint them when I re-assemble. This will save some money on the suspension rebuild by re-using the old A arms. The bushings threaded out ok, but the threads in the A arms were worn on one side. After re-installing the new bushings, we will carefully tack weld the bushing nut to the A arm itself.

The only challenge I see is getting the spacer shims for the front end alignment installed in a manner that will be fairly close, as the shims fell out when I removed the front end last summer and I didn't count the shims before I turned the wrench. Document, Document.........
 

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I'm confused... The upper A-arms I installed in my '66 didn't have any rubber in them (just the spring perches and the rubber boot around the ball joint). There are two metal "bushings" (the outer side threads into the upper A-arm stamping itself and the inner threads into the clevis, which allows has two bolts holes in it). The end of each bushing is hexoganol in shape and has a provision for a grease fitting.

Is this what you're talking about? If so, the purpose of threading the bushing onto the A-arm is to allow for adjustment and removal of the clevis as it wears. I suggest you don't tack weld the bushing to the A-arm, as this may affect the clevis wear rate.

I had both A-arms replaced with new parts (only one A-arm was replaced but both clevises and all four bushings) and adjusted for $100. I was worried about preload on the A-arm; I'd do it myself if I replaced them again.

Yup, I understand your comment on shims: how many and which bolt did it go under. I've had the same problem and now capture them in a suitably marked zip-lock baggie.

Oh yeah, one other thing: my lower A-arm joint (unibody side) moved off center on me. The suspension shop I had adjustments made at (toe-in, camber, caster) welded that back in place, centered of course. You might want to do the same.
 

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Discussion Starter #3
OK, now I'm confused. So tommorrow I'll inspect that bushing closer. What I thought was worn rubber inside the hollow part of the bushing may have actually been grease formed around the inside of the bushing. I thought originally the "bushing" was a two piece affair, ie, the hex nut with a rubber insert inside that the clevis ends fit into. The clevis ends do have a very course looking "thread" on them and I assumed you thread the ends into the rubber insert to allow for cushioning and anti rattle. I'll just need to check it out closer. The idea behind tack welding the bushings in is because of the worn threads on the A arm stamping. From what I understand, there is not a tremendous load on those bushings anyway, and a tack would help hold the bushing in place and could be ground later to allow for future adjustments. I may be ok with the threads on the A arm as they are, so they may not need extra attention such as welding. Its also hard to find a huge tap that size to clean up the threads, another rreason to try and justify the tack welds.
 
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I think there are o-rings or similar seals in the pivot bushings to hold the grease.

MustangSteve recommends tack welding the nuts to keeps them from working loose overtime. Check out www.mustangsteve.com and look of the FAQ page.

Personally, when I put in my new arms, I didn't tack weld them.
 

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Take a 1/16" cutoff wheel and make a groove across the threads. Here's an earlier post. Info is in the middle:

Here's a post from MustangSteve's web site on rebuilding:

Re: Question about rebuilding upper control arm
Posted by MustangSteve on 7/8/2002, 10:59 pm , in reply to "Re: Question about rebuilding upper control arm"
64.156.79.3

Pitch of shaft threads is exactly 1/2 that of the control arms, so they go together just fine. Read my FAQ article on installing upper a-frame bushings. Even if the 1-1/4" hex nut bushings DO tighten up to the torque specified, they will put the threaded bushings in a bind if you do it that way. You should adjust them so they turn freely on the threaded shaft, then tack weld them to the arm. Your misthreaded original a-frames are better than the reproduction unoits in my opinion,and are cheaper to rebuild and better in the long run.

Upper A-Frame Bushing Rebuild
When you remove the 3/4" nuts from inside the engine compartment, retrieve the alignment bushings from each of the 4 bolts (under the fender). Keep track of which ones went where and then put them back in their original locations when you reassemble. Tighten the 3/4" nuts very tight and they won't come loose. The real challenge is getting the new bushings screwed into place with the shaft centered exactly between the bushings and also not putting the bushings in a real tight bind by torqueing the large threaded bushing into the a-frame until it feels tight. The bushings will likely NOT tighten up in the a-frame without bending the sides of the a-frame towards each other. I tighten them until they are all the way in, but not necessarily tight. Then tack-weld every other flat on the hex of the bushing to the a-frame to keep them from backing out. IF YOU DON’T DO THAT, THE BUSHINGS WILL EITHER WEAR VERY RAPIDLY OR THE BUSHINGS WILL UNSCREW FROM THE ARM. (That is not a good thing).

Before putting the bushings onto the shaft, take a die grinder with a 1/16" wide cutoff wheel and cut a groove from the end of the shaft, across the threads, cutting slightly deeper than the root diameter of the threads, then into the o-ring sealing area. Do this only on the BOTTOM of the shaft. If you check the physics of it all, that side is never loaded, so it won't cause any additional wear. Deburr the slotted area. That slot achieves two things. 1. It allows the grease to have a path so it can reach EVERY thread on the shaft. Without it, the grease you pump in with your grease gun only gets to the first couple of threads, leaving the rest to give a SQUUEEEEKKK every time you hit the speed bump pulling into the local cruise night. and 2: It gives the grease a pathway to leak (slightly) past the o-ring so it doesn't hydraulically blow out the o-ring when you set the car back on the ground as the threaded bushing turns on the shaft, decreasing the volume of the area where the incompressible grease resides. Nothing worse than watching your brand new o-ring come oozing out from inside the bushing when you lower the car.

Before you let the car down, shoot the bushings full of grease, then remove all 4 zerk fittings. Let the car down slooowwwly and then bounce the front end up and down as much as you can. Now, reinstall the zerks and your bushings are properly greased with plenty of, but not too much, grease.

Here's the web site:
http://members.boardhost.com/MustangSteve/
 

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Discussion Starter #7
Thanks for the assistance guys. I appreciate the insight and the help. This will make the rebuild more sensible.
 

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Dan - Something you might consider before you invest a bunch of time and trouble (and $$) in those old arms. Canadian Mustang and Laurel Mtn both sell complete new control arm assemblies including new pivots, ball joints and (midolyne) bushings for about $130/pair. Just bolt them up. They are concours-correct (if that matters...) and guaranteed for life.

IMHO, beats the heck out of 40-year-old steel stampings that have been driven around for 200,000 miles.
 

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Man, Bill, those arms are beeee-utiful! How does their price compare with TCB and GW?
 
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