Spark Plug 4955850 4937472 5473010 – Fleet Supply for Cummins Engine
Spark Plug 4955850 4937472 5473010 — Cummins Gas Engine Ignition Replacement (cross-reference only) Compatible with ISB5.9G, ISC8.3, L9N, C8.3, ISL, QSL9 engines Copper core electrode with ceramic insulator rated to 1200°C Thread accuracy held to 0.01mm Plugs worn past service interval cause misfire and rough starts — full-set replacement keeps cylinder-to-cylinder balance and protects ignition coils from linked damage. Fleet replacement schedules and stocking guidance provided with shipment for predictable maintenance planning.