TRUCK TRANSMISSION PRODUCTION CODE EXPLANATION The truck transmission codes are located as Follows THREE SPEED SAGINAW TYPE The code is stamped on the left side of the case just below the side cover The production code number contains the source code model year and build date EXAMPLE N F A 10 SOURCE CODE MODEL YEAR BUILD MONTH DAY CODE S 3 Speed 1985 A Jan K Jul 10th Saginaw Type B Feb M Aug C Mar P Sept D Apr R Oct E May S Nov H Jun T Dec THREE SPEED TREMEC The identification code is located on upper left attachment ear top side The production code number contains the source code month model year and build sequence EXAMPLE SU G F OOO1 SOURCE CODE MONTH YEAR BUILD SEQUENCE Tremec A Jan G Jul 1985 B Feb H Aug C Mar J Sept D Apr K Oct E May L Nov F Jun M Dec 1991GENHMU MOTOHSSERWCEPARTSOPERAUONS LTTRUCK 526 1 91 4 1 4 000