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Service bulletins for the 2021 Ford F-550

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

237 on file from NHTSA, as of 2026-10-19.

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Only bulletins with topic: maintenance are shown. Show all

Bulletins, newest first
SSM 512512023-01-05. Service bulletin. ENGINE AND ENGINE COOLING. Some 2011-2022 F-Super Duty vehicles equipped with a 6.7L diesel engine may exhibit a ticking noise at idle after an engine oil change. It is often referred to as Typewriter Noise because of its similarity to the sound of a mechanical typewriter. When engine temperatures reach 150 °F (65 °C) or higher, (from engine idle up to approximately 1700 RPM's), this noise can typically be heard at the front wheel well and is often isolated to the transmission bell housing or oil pan area. Typewriter Noise is not detrimental to engine function or durability and has no short or long term effects on the engine. Do not attempt repairs to eliminate this noise. This noise is characteristic of the 6.7L diesel engine and will typically cease or diminish significantly within the oil change maintenance interval.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.