GARDNER MANNING ENG. HIN Decoder
Hull Identification Numbers beginning with GMJ were assigned by the US Coast Guard to GARDNER MANNING ENG. of SANTEE, CA. The company is recorded as out of business since 1989 — common for older hulls, and useful to know when hunting parts or records. Enter the full 12-character HIN below for build date, model year, and serial — free, no account.
MIC
GMJ
Location
SANTEE, CA
In business
since 1980
Status
Out of business (1989)
GARDNER MANNING ENG. built hulls across both HIN eras (1980–1989): boats before August 1984 carry legacy straight-year or model-year date codes; later hulls use the current month-letter format. The decoder handles all three.
Free · no account · the HIN is on the transom, upper starboard (right) corner
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GARDNER MANNING ENG. HIN FAQ
What does a GARDNER MANNING ENG. HIN look like?
It starts with the three characters "GMJ" — the Manufacturer Identification Code the US Coast Guard assigned to GARDNER MANNING ENG. — followed by a 5-character hull serial and a 4-character date code, 12 characters total. GARDNER MANNING ENG. built hulls across both HIN eras (1980–1989): boats before August 1984 carry legacy straight-year or model-year date codes; later hulls use the current month-letter format. The decoder handles all three.
Is GARDNER MANNING ENG. still in business?
USCG records list GARDNER MANNING ENG. as out of business since 1989. That's common for older hulls — the HIN still decodes normally, and the out-of-business date helps date the boat and guides parts-hunting toward salvage and owner groups rather than a dealer network.
How do I decode the year on a GARDNER MANNING ENG. HIN?
On current-format HINs the last two characters are the model year and the 9th–10th encode the certification month and year. GARDNER MANNING ENG. built hulls across both HIN eras (1980–1989): boats before August 1984 carry legacy straight-year or model-year date codes; later hulls use the current month-letter format. The decoder handles all three. Enter the full 12-character HIN above and the decoder works it out, including the legacy formats.
Other builders in CA
Sources: USCG Manufacturer Identification Code database (uscgboating.org, refreshed monthly) · HIN format per 33 CFR 181 subpart C. Cite this page: CarWhere, "GARDNER MANNING ENG. HIN Decoder," carwhere.com/hin-decoder/gmj, last verified 2026-06-12.