Lower control arm shaft replacement 70 c10 help
 

So I’m replacing the lower control arm shafts on my truck. What a pain in the ass. 1-5/8” socket? Good luck, got a big ass crescent wrench from harbor freight...

Anyways got them changed, the passenger side is smooth and falls on its own when pulled up, I had to keep tightening it till the slop was out of it though.

The driver side, from the start was hard to tighten and once tight, is very hard to move up and down. I’m thinking that it will loosen after time, but which is right?

Should they both be really tight or really loose and free?

Shafts are centered, I greased them (driver side not before installing, passenger side had some kind of lube on it). I’m not ok leaving it lie this, something is wrong.

Help
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Re: Lower control arm shaft replacement 70 c10 help
 

I think if they're centered pretty well they should be ok. I had the same concern when I did mine last year. I tried to get the shaft oriented with the index best I could before tightening down. Had to push pretty hard to get the arm down for installing the spring. I have a few hundred miles on mine since then. Seems to be ok so far.

Re: Lower control arm shaft replacement 70 c10 help
 

Thanks, then my concern may be the loose one I think. Do I need to get a breaker bar and pinch the control arm ears inward to get it tighter?
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Re: Lower control arm shaft replacement 70 c10 help
 

Don't know about that. You said you used a crescent wrench. Do you think you got pretty close to the torque spec? If so, I think I'd just leave it alone.

Re: Lower control arm shaft replacement 70 c10 help
 

Well I did use my foot to achieve final tightness till I couldn’t anymore. So one loose one tight but both solid should be ok?
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Re: Lower control arm shaft replacement 70 c10 help
 

Were they like this when you started? I'm getting ready to change mine, so this helps.

Re: Lower control arm shaft replacement 70 c10 help
 

The original rear bushings had play in them. That’s why I replaced them.
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Re: Lower control arm shaft replacement 70 c10 help
 

What’s the torque spec?
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Re: Lower control arm shaft replacement 70 c10 help
 

You need to consult a shop manual for this. I think the 3/4 tons are like 155 lb-ft and you won't do it with a crescent wrench, I don't think.

Plus it has all the steps on how to keep it centered and so on. Here's one page, it's well worth having...

Re: Lower control arm shaft replacement 70 c10 help
 

So I’m thinking about it, and the tight one, if I loosen just one of the ends all the way, the one that’s still tight will keep it centered and it should relieve the resistance then I retighten just the one. Hmmm, I think I’ll try and find a socket first though...

Thoughts?
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Re: Lower control arm shaft replacement 70 c10 help
 

I just got done doing mine and use an air impact with a socket to get them on. The breaker bar and cheater pipe were killing me. I did grease the threads on the cups before I started. I didn't at first and then had second thoughts and pulled it back apart and put grease. When I got done and put the grease fittings in it didn't take much more grease to fill them up.

I ran them down with the air impact and then went the last little bit with the breaker bar and torque wrench. I'm pretty sure it took more torque than the final torque spec just to get them installed. I did have one that really wouldn't budge once it was tight and ended up loosening the caps a little because I couldn't rotate the shaft to line up the dimple. Put the torque wrench back on and it still clicked after loosening.

I'm not sure exactly what is being torqued here because normally when you are tightening a bolt you are stretching it a certain amount. Those lower shafts are so big I can't imagine they are stretching much.

This thread has some good info:
http://67-72chevytrucks.com/vboard/s...d.php?t=544901

I found that thread because I was looking for what MOOG said to torque the bolts to. 100 ft/lb which is less than the factory manual.

Mine ended up with one arm that would stay in whatever position you put it and one that drooped when you let go. I figured it would be fine since they both moved freely and had grease on the threads.

Re: Lower control arm shaft replacement 70 c10 help
 

Mine were about the same after torque and install ( with grease on the threads prior to assembly ). One was real tight and the other was much less tight, both centered. This was achieved with BIG pipe wrench and full body weight with cheater.

It's been fine since so I think you're going to be OK. These parts are so rigid and beefy it'd take a real bad install to create a safety issue ( except maybe for the U-bolts--get carried away with the torque there is not a good idea ).

-klb

Re: Lower control arm shaft replacement 70 c10 help
 

This looks like its for the uppers so the torque spec of 80 seems unreal for an 1-5/8" suspension nut.

Re: Lower control arm shaft replacement 70 c10 help
 

Ok so I got a hold of a socket and a nice sized 3/4” ratchet. I loosened the rear nut on the tight control arm, pulled it off, greased it again, and reinstalled. What do you know, it’s nice and smooth like the passenger side now. All is good!
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Re: Lower control arm shaft replacement 70 c10 help
 

When I did mine I counted each rotation or partial rotation so that the caps were turned on the exact same number of turns. Don't know if that's the "right" way to do it, but the wheels haven't fallen off yet!