Engine Mechanical
Rocker Arm
A rocker arm transfers motion from the camshaft to the valves, opening them at the right moment. We list 33 rocker arms from $6 to $147 by Melling, Mopar, AC Delco, SKP and Crown Automotive, with most fitments for Dodge Dakota, Ram 1500, Ram 2500 and Chevrolet Malibu engines.
Shop rocker arm by vehicle
Signs of a worn rocker arm
A ticking or tapping noise from the top of the engine is a common sign, though lifters and low oil can cause the same sound. Worn rocker tips, a broken arm, or a seized roller can lead to a misfire and a check engine light.
If you remove a valve cover and find a broken rocker or a bent pushrod, check the lifters, valve springs and camshaft lobes too. Metal debris also calls for an oil change and a look at the filter.
Types and positions
This group includes stamped steel, cast steel and roller rocker arms, plus switching cam followers used on some newer engines. Roller designs reduce friction where the arm meets the valve or cam.
Some engines use different arms for intake and exhaust valves, or for left and right banks. Listings show position, so match the location you are replacing. Check the fitment table for your engine, since one model may offer several engines.
Installation tips
Keep parts in order as you remove them and reinstall any reused parts in the same spot. Coat the contact points with engine oil or assembly lube.
Tighten rocker bolts to the factory torque spec, and set lash or preload if your engine requires it. Turn the engine by hand so each lifter is on the base circle of its cam lobe before tightening. A new valve cover gasket is usually needed.
Rocker Arm questions
Can a bad rocker arm cause a misfire?
Yes. If a rocker breaks or wears badly, the valve may not open fully or at all, and that cylinder will misfire. A compression test or visual check under the valve cover can confirm it.
Should I replace all rocker arms at once?
If one has failed from wear, others may be close. On high mileage engines, replacing the set is common. If one broke from a single cause, replacing that arm and checking the rest may be enough.
What is the difference between roller and non-roller rocker arms?
Roller rocker arms have a small wheel or bearing that reduces friction at the contact points. Non-roller arms slide against the valve tip or cam. Use the type your engine was designed for unless you are building a performance engine.