Re: W Olds rearend codes? W-27
2 letter codes are reused in different years and meant different things. In 1971, Olds stopped using their own design 12 bolt rear end and began manufacturing and using the corporate 10.5 design.
The two letter codes were used to build the cars originally, not identify them later. Actual part number stamps are about the only positive id even though we didn't use them in the assembly plant. The broadcast "build sheets" referred to these codes in the mfg. process.
The assembly lines were stripped of non carryover parts as the last car went down the line for the model year. Carryover parts were moved to the new point of use location (if relocated due to a process or line layout change.) As long asa the old parts wer removed from the plant, the same 2 letter code was reused on new year parts.
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