https://partsnow.ai/guides Heavy-duty truck parts buying guides with live catalog pricing. en-us https://partsnow.ai/guides/best-air-dryers-class-8 https://partsnow.ai/guides/best-air-dryers-class-8 For most Class 8 fleets, a quality AD-9 style air dryer assembly or OEM spin-on cartridge replaced every 12 months (or 100k miles) keeps moisture out of the brake system. Our top picks balance catalog availability, price, and common Bendix/Wabco cross-reference coverage. Wed, 01 Jul 2026 00:00:00 GMT https://partsnow.ai/guides/brake-drum-cast-vs-lightweight https://partsnow.ai/guides/brake-drum-cast-vs-lightweight Cast brake drums remain the fleet default for durability and heat capacity on drive axles; lightweight drums can save unsprung weight on steer positions where permitted. Match diameter, width, and bolt circle to your existing drum — 16.5×7 is the most common Class 8 drive spec. Wed, 01 Jul 2026 00:00:00 GMT https://partsnow.ai/guides/best-fuel-filters-class-8 https://partsnow.ai/guides/best-fuel-filters-class-8 Class 8 fuel filters should be changed per OEM interval — typically every 15k–30k miles depending on fuel quality. A primary separator plus secondary element setup protects injectors on modern high-pressure common-rail engines. Thu, 02 Jul 2026 00:00:00 GMT https://partsnow.ai/guides/best-oil-filters-heavy-duty https://partsnow.ai/guides/best-oil-filters-heavy-duty Heavy-duty oil filters should match your engine's thread, bypass valve spec, and micron rating. Most fleets stock one primary element per engine family and change at every oil drain — typically 25k–50k miles for long-haul applications. Thu, 02 Jul 2026 00:00:00 GMT https://partsnow.ai/guides/best-type-30-brake-chambers https://partsnow.ai/guides/best-type-30-brake-chambers Type 30 (3030) chambers are the standard spring brake actuator on most Class 8 drive and trailer axles. Match stroke length (standard vs long-stroke), mounting bracket, and clevis pin size to your existing chamber before ordering. Fri, 03 Jul 2026 00:00:00 GMT https://partsnow.ai/guides/best-automatic-slack-adjusters https://partsnow.ai/guides/best-automatic-slack-adjusters Automatic slack adjusters maintain brake stroke within FMCSA limits without manual adjustment. Match spline count, arm length, and chamber type to your axle — incorrect adjuster geometry causes uneven lining wear and out-of-service brake violations. Fri, 03 Jul 2026 00:00:00 GMT https://partsnow.ai/guides/kenworth-t680-clutch-replacement-cost https://partsnow.ai/guides/kenworth-t680-clutch-replacement-cost A Kenworth T680 clutch kit typically runs $800–$2,500 for parts alone depending on transmission (Eaton Fuller vs PACCAR) and clutch diameter. Labor adds 6–10 shop hours. Our picks reflect common Eaton-style kits stocked for Class 8 over-the-road applications. Sat, 04 Jul 2026 00:00:00 GMT https://partsnow.ai/guides/best-u-joints-heavy-duty https://partsnow.ai/guides/best-u-joints-heavy-duty Heavy-duty U-joints should be inspected every 50k miles and replaced when play exceeds spec. Match series (1310, 1330, 7290), cap diameter, and strap vs U-bolt style to your existing driveshaft — mixing series causes premature failure. Sun, 05 Jul 2026 00:00:00 GMT https://partsnow.ai/guides/best-wheel-seals-oil-bath https://partsnow.ai/guides/best-wheel-seals-oil-bath Oil-bath hub seals fail from heat, contamination, and worn wear rings — replace the seal and inspect the wear ring at every wheel-end service. Match seal OD/ID to your hub manufacturer (Stemco, Meritor, etc.) and confirm axle type (steer vs drive). Mon, 06 Jul 2026 00:00:00 GMT https://partsnow.ai/guides/best-engine-air-filters-class-8 https://partsnow.ai/guides/best-engine-air-filters-class-8 Engine air filters on Class 8 trucks should be inspected at every PM and replaced when restriction indicators trip or at OEM interval. A clogged filter reduces fuel economy and increases turbo wear — stock one primary and one safety element where applicable. Tue, 07 Jul 2026 00:00:00 GMT