Johnny Joint Primer Needed

AndyG

Because some other guys are perverts
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When I go to the website , i see joint after joint that look similar and my brain just melts-

On an upcoming LJ project I think i need left hand and right and with 1 1/4” threads, and pretty sure I need 1” or 7/8 “ left and right hand for the uppers-

What are the critical numbers to look at when ordering? How do I read these to know the bolt size and bracket fitment.

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Chris can you put this in the TJ section please , thanks sir.
 
What are you trying to do?

The "size" of the Johnny joint is the width of bracket you'll need on the axle or frame. So, the LCA's for our TJ's are a 2.5" Johnny Joint. Uppers are a 2." Your brackets should be about that wide inside.

As far as the threads for the tubing it screws into, you need to match whatcha got, or if you're threading your own, its dealers choice. The Rock Jock MFG ones for a TJ are 1" - 14 for the lowers. The uppers are 1" tube, so I'd assume they are a 3/4-16 thread...but I haven't verified that.
 
What are you trying to do?

The "size" of the Johnny joint is the width of bracket you'll need on the axle or frame. So, the LCA's for our TJ's are a 2.5" Johnny Joint. Uppers are a 2." Your brackets should be about that wide inside.

As far as the threads for the tubing it screws into, you need to match whatcha got, or if you're threading your own, its dealers choice. The Rock Jock MFG ones for a TJ are 1" - 14 for the lowers. The uppers are 1" tube, so I'd assume they are a 3/4-16 thread...but I haven't verified that.
Thanks, replace CA joints on an unknown set up-

Do all accept basically the same bolt to bolt them to the bracket?

I’m thinking I need one each 2 1/2” right and left hand for each lower arm with 1 1/4” x 12 threads and 2” with the 7/8 x 14 threads for the uppers, provided the arms are threaded that size, and new bolts.

All the ball size numbers confuse me and making sure the bolt diameter is correct is a concern -

Does that make sense?
 
the ball size is the bolt size. a .640 is gonna be close to 5/8" the .718 is like an 18mm. both to big.

IIRC you want 7/16 on top and 9/16 on the bottom.

2.625 is 2 5/8" and that what our lower links mounts are.
and again IIRC the upper it 2"

but the holes you want are like .54-.56 (lower) and .43-.45 (upper) . more in this ball park, those you have shown require larger bolts.

1.25" shank is pretty common on the lowers but you sure the uppers not 1"?

D to F to MM.PNG
 
the ball size is the bolt size. a .640 is gonna be close to 5/8" the .718 is like an 18mm. both to big.

IIRC you want 7/16 on top and 9/16 on the bottom.

2.625 is 2 5/8" and that what our lower links mounts are.
and again IIRC the upper it 2"

but the holes you want are like .54-.56 (lower) and .43-.45 (upper) . more in this ball park, those you have shown require larger bolts.

1.25" shank is pretty common on the lowers but you sure the uppers not 1"?

View attachment 283239
Makes sense, i just picked a shot at random- makes perfect sense and huge help