Author Topic: Lower control arm issue  (Read 1311 times)

Offline Rich10

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Lower control arm issue
« on: November 08, 2021, 05:41:51 PM »
Hi guys,

I’ve got a ‘77 C10.

I needed to replace my lower control arms.  They were really bad.

We’ll, I screwed up. I ordered 3/4 ton c20 lower arms for my 1/2 ton C10. As far as I can tell, they’re the same as 1/2 ton except for the lower ball joint.  The problem is that the 3/4 ton ball joint is larger than a 1/2 ton and the ball joint won’t slide into the spindle.

Has anyone reemed their spindle for the larger lower ball joint?
Or
Is there a 1/2 ton ball joint that’s a large OD to fit the 3/4 size (like a combination ball joint)?

Any other options?

Thanks

Offline JohnnyPopper

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Re: Lower control arm issue
« Reply #1 on: November 08, 2021, 10:15:25 PM »
My understanding is that the 1/2 to 1 ton arms fit the same foot print. But as the wearable component grow to accommodate the higher load, the spec's change.

How bad were the original arms? Bushing, ball joints, aren't dependent on the arms unless they are deformed, bent, etc..

1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline Rich10

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Re: Lower control arm issue
« Reply #2 on: November 09, 2021, 06:24:53 AM »
My understanding is that the 1/2 to 1 ton arms fit the same foot print. But as the wearable component grow to accommodate the higher load, the spec's change.

How bad were the original arms? Bushing, ball joints, aren't dependent on the arms unless they are deformed, bent, etc..

Yes, the arms are the same size.  I think the only difference is the shaft and ball joint.

The old arms were rotted and bent. 

Offline VileZambonie

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Re: Lower control arm issue
« Reply #3 on: November 09, 2021, 05:51:34 PM »
as long as you are willing to and can properly do it, you could ream the knuckle to accept the shank. People do it all of the time on their Jeeps.
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74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline Chevygold

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Re: Lower control arm issue
« Reply #4 on: January 31, 2022, 07:31:20 AM »
Hi Rich, looks like I may need to do the same as 1/2t lower arms are like hens teeth, both my lower arms look to have been damaged by some rough recovery at some time distorting the eyes where the bushes fit.Could you give me the details of the reamer you used please so I can get the same to be sure the taper matches the larger ball joints. btw mines a 76 C10 1/2t.
Many Thanks
Graham