P0306 on a Ram 1500

What P0306 usually means on a 1500

P0306 isolates a misfire to cylinder 6 on the Ram 1500. On the 5.7 HEMI cylinder 6 is another of the MDS cylinder-deactivation cylinders, placing it among the usual suspects for the engine's known collapsed-lifter and worn-camshaft failures. A cylinder-6 misfire that comes with a persistent tick should prompt a valvetrain inspection rather than repeated ignition-part swaps. As always, confirm the cheap causes, the coil, plug, and injector, before committing to major work.

Most likely causes on this model

1. HEMI MDS lifter or cam lobe on cylinder 6

   Cylinder 6 deactivates under MDS, so a collapsed lifter or flat lobe there is a common HEMI cause, usually with a tick.

2. Coil or plug on cylinder 6

   A swap test quickly rules ignition in or out at low cost.

3. Cylinder 6 fuel injector

   A clogged injector starves that cylinder and mimics an ignition fault.

4. Low compression on cylinder 6

   A leak-down confirms whether the misfire is mechanical from lifter damage or a burnt valve.

What it costs on a 1500

A coil or plug fix is minor and cheap; a confirmed lifter and camshaft repair is a major four-figure job. Because cylinder 6 is an MDS cylinder and the HEMI is prone to lifter failure there, a leak-down or borescope inspection before parts is money well spent, especially if you hear a tick.

Fixing it

If cylinder 6 keeps misfiring after a coil and plug swap and the engine ticks, have the MDS lifters and cam lobes inspected; catching a collapsing lifter early can prevent a wiped cam and metal debris throughout the engine.

For the full step-by-step diagnosis order (any vehicle), see the main P0306 guide.

Other codes we cover on the Ram 1500