The Rear Main Seal fits the Cadillac V8 1937-48 with 346 cubic inch engines and the LaSalle V8 1937-40 with 322 cubic inch engines, however take note that the rear main seal in not actually used in the 1937 models.
Best set #5117S
Made in the USA!
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1937-48 Cadillac V8 and 1937-40 LaSalle V8 Rear Main Seal for the 346 and 322 cubic inch engines