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Recommended Service Interval

Recommended PCV Valve Replacement Interval

1966-71 Vehicles - Every 12,000 Miles.

1972-74 Light, Medium And Heavy Duty Vehicles - Every 24,000 Miles.

1975-76 Light Duty Vehicles - Every 30,000 Miles.

1975-76 Medium And Heavy Duty Vehicles - Every 24,000 Miles.

1977-82 Light Duty Vehicles With Light Duty Emission Package - Every 30,000 Miles.

1977-82 Light Duty Vehicles With Heavy Duty Emission Package - Every 24,000 Miles.

1977-82 Medium And Heavy Duty Vehicles - Every 24,000 Miles.

NOTE: If a 1977-82 medium and heavy duty vehicle is operated involving extensive idling and/or short trip use at freezing temperatures--where the engine does not become thoroughly warmed-up--replace PCV valve every 12,000 miles.