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This decoder indicates 1987 W150 , 4WD, standard cab (not extended), short bed equipped with 5.2 liter V8, carbureted. Assembly plant Warren Michigan which was the only facility building Dodge trucks in that era.
First position character "1" indicates assembly plant country of origin. United States assembly plants are coded 1, 4, or 5.
Second position character "B" indicates manufacturer; B is for Dodge.
Position 8 character "T" indicates engine code; T is for 5.2 liter V8 carbureted.
Position 10 character "H" indicates model year; H is for year 1987.
Position 11 character "S" indicates manufacturer unique code for all its assembly plants. S is for Warren truck assembly.