Please check notes in each part listing to ensure the Differential Pinion Seal is correct for your 1965 PONTIAC GTO with a 6.4L 389 engine. USA STANDARD GEAR & NATIONAL are competing brands, and each brand's Differential Pinion Seal may be interchangeable. Special restrictions like "California only" or "with sport package" may indicate a Differential Pinion Seal fits only certain 1965 PONTIAC GTO models.
Clicking a "More Info" link will display a picture and/or other details about that Differential Pinion Seal in a separate window (you may need to turn off your pop-up-blocking software for this to work).
After choosing a Differential Pinion 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 Drivetrain parts, other PONTIAC GTO 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 1965 PONTIAC will not be lost if you switch.