The second choice when selecting a rod end is the spherical rod end.
Spherical rod ends, also referred to as the Heim Joint named after the inventor Lewis Heim who founded the Heim Bearing Company, can be used for these heavy-duty applications but are also used in linkages where the load is much lighter. They are available in a wide variety of sizes and construction, so you must choose the one designed for the application you intend to use it for. This can be quite a challenge because no one wants to be liable for anything that happens to you if the part they recommend is not proper for the application.
The sources that I used for spherical rod ends are placed in two categories:
1-Those primarily serving the aircraft and military / aerospace and industrial markets. This includes: Aurora Bearing Company and RBC Bearings / Heim.
2-Those who specialize in serving the automotive market. This includes: QA1, Speedway and DMP Fasteners / FK Rod Ends.
All of these sources were very helpful in supplying technical information and making recommendations for which rod end that I should use for a given application. However, they must deny any liability for anything that happens as a result of the use of the rod ends because they have no control over the way that you use them.
My roadster project uses both types of rod ends. The split wishbones utilize the standard OEM style rod ends. The tie rod, drag link Panhard bars and shock links all use heavy-duty spherical rod ends. I could have used the spherical rod ends for the split wishbones but the OEM style tie rod ends were part of the original PSI kit.
The original spherical rod ends for the tie rod, drag link and Panhard bars were all installed in the ‘70s, so they were replaced with new stainless heavy-duty rod ends because spherical rod ends have improved considerably in both strength and quality since then.