{"product_id":"national-304-dd-manual-transmission-countershaft-bearing","title":"National 304-DD Manual Transmission Countershaft Bearing - Center or Rear","description":"\u003ch2\u003eOverview of National 304-DD Manual Transmission Countershaft Bearing\u003c\/h2\u003e\u003cp\u003eThe National 304-DD is a precision-engineered manual transmission countershaft bearing designed for reliable performance in select Ford, Mercury, Nissan, and Toyota vehicles. This single row radial ball bearing supports smooth countershaft rotation, essential for maintaining transmission efficiency and longevity.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eSingle row radial design for consistent load handling\u003c\/li\u003e\n\u003cli\u003e0.787 inch (20 mm) bore diameter for precise fitment\u003c\/li\u003e\n\u003cli\u003eOuter diameter of 2.047 inches (52 mm) ensuring compatibility with specified transmissions\u003c\/li\u003e\n\u003cli\u003eWidth of 0.591 inches (15 mm) for optimal space utilization\u003c\/li\u003e\n\u003cli\u003eInner and outer race radii of 0.040 inches (1.02 mm) for durability and reduced wear\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eTechnical Specifications and Design Details\u003c\/h2\u003e\u003cp\u003eThe National 304-DD bearing features a 20 mm inner race bore and a 52 mm outer diameter, making it suitable for manual transmission countershafts in various vehicle models. Its single row radial ball bearing design supports radial loads effectively, contributing to smooth gear engagement and reduced friction. The bearing’s inner race width and outer race width both measure 15 mm, providing balanced support within the transmission assembly. The A-7 type and 300 series classification indicate its standardized dimensions and performance characteristics, aligning with OEM requirements.\u003c\/p\u003e\u003ch2\u003eCompatible Vehicles and Applications\u003c\/h2\u003e\u003cp\u003eThis manual transmission countershaft bearing is compatible with a range of Ford, Mercury, Nissan, and Toyota models, including but not limited to:\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFord F-100, F-250, F-350, E-250 Econoline, E-350 Econoline, and Econoline Club Wagon variants\u003c\/li\u003e\n\u003cli\u003eMercury Colony Park and Marauder\u003c\/li\u003e\n\u003cli\u003eNissan Pickup\u003c\/li\u003e\n\u003cli\u003eToyota Land Cruiser and LTD\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eUsing the National 304-DD bearing ensures proper fitment and reliable operation within these specific manual transmission systems.\u003c\/p\u003e\u003ch2\u003eCommon Issues Addressed by the 304-DD Bearing\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eExcessive transmission noise due to worn or damaged countershaft bearings\u003c\/li\u003e\n\u003cli\u003eVibration or rough gear shifting caused by bearing failure\u003c\/li\u003e\n\u003cli\u003ePremature wear of transmission components from inadequate bearing support\u003c\/li\u003e\n\u003cli\u003eOverheating in the transmission assembly linked to bearing friction\u003c\/li\u003e\n\u003cli\u003eReduced transmission efficiency and potential gear slippage\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eInstallation Notes and Tips\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eEnsure the transmission is clean and free of debris before installation\u003c\/li\u003e\n\u003cli\u003eUse proper tools to press the bearing onto the countershaft without damaging the races\u003c\/li\u003e\n\u003cli\u003eVerify the bearing orientation matches OEM specifications\u003c\/li\u003e\n\u003cli\u003eCheck for smooth rotation after installation to confirm correct fitment\u003c\/li\u003e\n\u003cli\u003eConsult vehicle-specific service manuals for torque and assembly procedures\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eQuality Assurance and Warranty Information\u003c\/h2\u003e\u003cp\u003eNational bearings are manufactured to meet industry standards for durability and performance. The 304-DD manual transmission countershaft bearing undergoes rigorous quality control to ensure dimensional accuracy and material integrity. While specific warranty terms may vary, National typically offers coverage against manufacturing defects, providing confidence in the product’s reliability for compatible Ford, Mercury, Nissan, and Toyota transmissions.\u003c\/p\u003e","brand":"National","offers":[{"title":"Default Title","offer_id":43446449864885,"sku":"BCZK-304-DD","price":52.74,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0628\/1442\/1173\/files\/NS_304DD_Ang.jpg?v=1774734488","url":"https:\/\/www.partcatalog.com\/products\/national-304-dd-manual-transmission-countershaft-bearing","provider":"PartCatalog","version":"1.0","type":"link"}