Please check notes in each part listing to ensure the Fluid Pump Seal is correct for your 1975 GMC C15 SUBURBAN with a 5.7L 350 engine. ATP & NATIONAL are competing brands, and each brand's Fluid Pump Seal may be interchangeable. Special restrictions like "California only" or "with sport package" may indicate a Fluid Pump Seal fits only certain 1975 GMC C15 SUBURBAN models.
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After choosing a Fluid Pump Seal, click the "Add Part" button. Shipping costs will be shown on the Shopping Cart page. You may use your browser's Back button or click "Find More Parts" to find more Transmission-Automatic parts, other GMC C15 SUBURBAN parts or parts for a different vehicle. Please try our Interactive Catalog (click link above) for faster searching. Both catalogs use the same shopping cart so any auto parts you've already chosen for your 1975 GMC will not be lost if you switch.