Rod Ends & Heim Joints

Does your project need a joint that moves freely in several directions without the flex rubber bushings can introduce? Rod ends and heim joints sit at the ends of adjustable rods, arms and links, and are for you if you build or fine-tune suspension.

What rod ends do in the suspension

A rod end consists of a ball that can rotate and tilt inside a housing with a threaded shank. The joint is typically used on adjustable control arms and suspension rods and links, where length and geometry need to be set precisely. Compared with rubber bushings, it can give more direct handling, but it can also transmit more noise and vibration into the body.

How to choose the right rod end

Start with the dimensions, and check them for the specific part number:

• Bore and thread: the bore must match the bolt and the thread must match the rod, e.g. .625in bore with 5/8-18 or .75in bore with 3/4-16.
• Male or female and thread direction: with right-hand thread at one end and left-hand thread at the other, the rod length can typically be adjusted by turning the tube without removing the ends.
• Construction and material: QA1 offers, for example, the C Series as 2-piece in carbon steel, the H Series as 3-piece in alloy steel and the A Series Endura in aluminium. Load, weight and use determine the choice.

Heavier-duty joints are also available, such as the forged RockJock Johnny Joint. The category also includes parts from Rock Krawler, King Shocks and Artec Industries.

Installation and maintenance

Tighten to the specified torque, and lock the jam nut once the geometry is set. The joint's angular movement must stay within its limits, otherwise the housing can hit the shank. Joints with a grease nipple can be lubricated as needed, while others are designed to run without. Check the wheel alignment after installation; for larger changes, camber and caster kits may also be relevant.

Frequently asked questions

What is the difference between 2-piece and 3-piece rod ends?

A 2-piece rod end typically consists of a housing and a ball, while a 3-piece has an extra liner between them. The construction can affect play, friction and durability under load, so the choice depends on use and the specific product.

Can I fit rod ends to a car that has to pass inspection?

It depends on the product, the car and where the joint is fitted. Changes to suspension and steering may require approval, so check the requirements and documentation for the specific part number before fitting to a registered car.

How do I spot a worn rod end?

Typical signs are noticeable play when you pull on the joint, clunks over bumps and wheel alignment that changes. Rust or rough movement in the ball can also mean the joint should be replaced. At the same time, check that the jam nut is tight.