Failure mode - Ford 7.3L Godzilla Gasoline (Super Duty 2020+, E-Series cutaway 2021+)

Broken valve springs (sudden single-cylinder misfire)

Reliability tier: aggregated - verify before ordering, see /disclosure/

Symptoms

sudden rough running / flashing misfire light on one cylinder, often at speed
compression miss that follows the cylinder, not the coil or injector
cited on owner forums; not one NHTSA complaint on 2020+ gas Super Duty trucks names a valve spring (checked 2026-10-14)

Compare with the other causes of the same sign on this engine: misfire, rough idle, hesitation or surging (3 causes)

Root cause

Owner forums document abrupt spring failures producing a dead cylinder. The open record has no authoritative failure-rate statistics and no confirmed single root cause (forum discussion includes oil-drainback and spring-spec theories - unproven). Engine is otherwise regarded as durable.

Diagnosis

confirm the miss follows the cylinder: swap coil and plug across cylinders or use relative-compression test
leak-down / compression test on the dead cylinder before pulling the valve cover
inspect the spring hardware on the dead cylinder and, on a high-mileage engine, consider surveying the rest

Fixes

replace the failed spring(s) with updated hardware; on a high-mileage engine survey remaining springs ()

valvetrain - more than one option: 7.3L/6.8L Godzilla Camshaft, 2023+ (OEM), 7.3L/6.8L Godzilla Push Rod (OEM), Godzilla Rocker Arm Pivot, left (OEM), Godzilla Rocker Arm Pivot, left (current PN VC3Z-6A585-B), Godzilla Rocker Arm Pivot, right (OEM), Godzilla Rocker Arm Pivot, right (current PN VC3Z-6A585-A), 7.3L/6.8L Godzilla Valve Cover Gasket, 2023+ (OEM), 7.3L/6.8L Godzilla Valve Lifter, 2023+ (OEM), 7.3L/6.8L Godzilla Valve Spring (OEM, current hardware)

if a dropped valve damaged the head/piston, that is an engine-level repair, not a spring swap ()

valvetrain - more than one option: 7.3L/6.8L Godzilla Camshaft, 2023+ (OEM), 7.3L/6.8L Godzilla Push Rod (OEM), Godzilla Rocker Arm Pivot, left (OEM), Godzilla Rocker Arm Pivot, left (current PN VC3Z-6A585-B), Godzilla Rocker Arm Pivot, right (OEM), Godzilla Rocker Arm Pivot, right (current PN VC3Z-6A585-A), 7.3L/6.8L Godzilla Valve Cover Gasket, 2023+ (OEM), 7.3L/6.8L Godzilla Valve Lifter, 2023+ (OEM), 7.3L/6.8L Godzilla Valve Spring (OEM, current hardware)

Prevalence

occasional