Doesn't that kind of defeat the purpose of solid rod ends if the there is a difference between the ID of the ball (.625" on a standard 3/4" rod end) and the OD of the OEM M12 bolt (.472" nominal according to https://www.google.com/url?sa=t&sour...GNIR344ws3ho_Q and https://www.google.com/url?sa=t&sour...4US1unmUmCDNSA)? That leaves over .050" max slack. Or are we supposed to presume the bolt and nut torque is high enough to hold the rod end's ball still?

 

We machine rod-end spaces that insert into either side of the rod end to take up the space between the width of the rod end and the factory mount. We also drill the centers on them to more accurately fit the 12mm bolts

 

Like BMR said. Most if not all aftermarket lower control arms that use 3/4" spherical rod ends will supply the arms with reducer bushings. These bushings will go from .750" to 12mm along with taking up the extra space between the rod ends and the chassis/axle mounts.

 

This was my nightmare for awhile with my aftermarket tubular suspension components. A lot of noise in the rear even with poly/rod combos. Like you said, the stock bolts are metric and most aftermarket parts are SAE poly/rod ends. To make matters worse my new panhard bushings were 9/16''id and the stock bolts are 12mm.... clunk clunk bang

I have since bored out my stock mounting locations to SAE 1/2'' and 9/16'' grade 8.8 to match. Most of us dont plan on reusing the stock components anyway.

 

Boosted, that's what I saw somewhere that other guys have done. I'm guessing now the parts makers are machining the spacers to also be the SAE to metric "adapter" as well. I know that in the pro mod world, there are NAS bolts designed to be extra strong in the shear load vector that are solid with no threads until the very end for the washer and nut. Thinking about going that route.

 

I just remembered I bought correct SAE grade 9 yellow zinc - not 8.8. I forget whats equivalent to metric 8.8-10.9. Grade 9 is strong enough, and fastenal sells them online for a steal. They have shouldered versions.