Ball Joint Control Arms

[jamesbissland]

Hi All,

Are the top control arms on a ball joint beam the same casting, with the ball joint just being pressed in from the opposite side?

Some retailers sell them as the same, and some sell as left and right handed

Thanks in advance
James

[FJCamper]

James, the ball joints press into a taper fit, which would make a left and right hand part. I've never hear of a universal left/right upper arm. It's true you can slide an upper arm on either side of a torsion tube and the geometry stays the same, and I'll take it as possible that some mfg has made universal arms.

Now you've given me something to worry about! Anybody got a better answer than me?

[jamesbissland]

Thanks FJC!

The problem i have is, Ive pulled my trailing arm out, had the old ball joints pressed out and then stripped ready for new balljoints and painting, but now I cant tell them apart!
The ball joint alignment marks (what I can see of them) appear to be on the same side for both arms
I tried to do a bit of research into any distinguishable differences, and found this tech info from a reputable parts dealer / website, which made me think maybe they are the same...

Screen Shot 2021-04-25 at 7.10.20 AM.png

They both have the VW symbols on with a couple random numbers, but neither make any sense

So, if I was to measure the diameter of the hole for the ball joint with some calipers I should see it taper in the direction that the ball joint would be pressed in?

Is there any other way of telling them apart?

Thanks so much in advance!
JB

[Ian Godfrey]

i have always relied on the marks for lining up the ball joints.
that is odd you seem to have 2 the same. I'll be interested to see if you find a taper.

[jamesbissland]

So the plot thickens.......

I have 4 sets of vernier calipers.. do you think I could find any of them? Another trip down to the hardware store tomorrow.

I found another set of control arms from a local guy who had also already pressed the ball joints out.
I cleaned up the area where the mark are usual found... these have them!... on both sides!!

So no further ahead with identifying what one is left and what is right.

I tried measuring the holes with a tape measure to see if there was a obvious taper, but couldnt distinguish a difference. Had to try

Does any one have any further info?

[Bruce2]

There isn't any taper.
I've purposely swapped them L to R to see if it can be done. It makes no difference what side they go on. The ball joints press in with the same force either way.
On a couple of control arms, I thought I saw a slight chamfer on the end that VW originally pressed the first BJ into.

[FJCamper]

Bruce, thanks for the info. In that all we have now is used or rebuilts, a universal left/right fit is a good thing.

[jamesbissland]

This is fantastic info!

Thank you to all who have contributed both direct to me and publicly on this forum.

Hopefully this information will help others out that have found themselves out in the same predicament as me in the future!

Cheers!