Pushrods

Have you changed the camshaft, had the cylinder head skimmed or fitted new rocker arms, so the valvetrain geometry no longer lines up? Then pushrods in the correct length can put it right. We stock fixed and adjustable pushrods, individually and in sets, for engines with the camshaft in the block.

What pushrods do in the valvetrain

The pushrod transfers the motion from the lifter on the camshaft up to the rocker arm, which opens the valve. The rod must be stiff enough not to flex under load, and its length determines where the rocker arm contacts the valve stem. The wrong length can cause uneven valve actuation and increased wear on the valve stem and valve guides.

How to choose pushrods

The choice depends on the entire valvetrain, not just the engine type:

• Length: measure with an adjustable checking pushrod with the actual parts installed, especially after changes to the camshaft, cylinder head, gasket or rocker arms.
• Diameter and wall thickness: higher lift and stronger valve springs can require a stiffer pushrod, but also check the clearance in the cylinder head and any guide plates.
• End types: the ends must match both the lifter and the rocker arm.
• Fixed or adjustable: fixed sets are available from e.g. Edelbrock and COMP Cams, while S&S Cycle offers adjustable sets, e.g. for M8 models. OMIX has single pushrods, e.g. for the 3.8 and 4.2L in Jeep CJ & Wrangler 78-90.

Installation and inspection

Roll each pushrod on a flat surface to make sure it is straight, and lubricate the ends with assembly lube. If the pushrods are hollow and feed oil to the rocker arms, the oil passage must be clear. Set the valve lash according to the instructions for the specific engine. See also the rest of our camshafts and valvetrain.

Frequently asked questions

How do I find the right pushrod length?

Use an adjustable checking pushrod with the actual parts installed, and check the rocker arm's contact pattern on the valve stem. The correct length depends on the camshaft, lifters, cylinder head, gasket and rocker arms.

What is the difference between fixed and adjustable pushrods?

Fixed pushrods have one set length and are used when the correct length is known. Adjustable pushrods can be set to length. Which type the engine requires depends on how the valve lash is adjusted in the specific valvetrain.

When should pushrods be replaced?

When a pushrod is bent, has worn ends or does not roll straight on a flat surface. A bent pushrod can be caused by excessive revs, failing valve springs or incorrect adjustment, so find the cause before replacing it.