Frequently Asked Questions About Kenworth W900B/W900L Drum Brake Parts

What years do these drum brake parts fit, and are they compatible with both W900B and W900L models?

Our drum brake parts are designed to fit Kenworth W900B models from 1987-2007 and W900L models from 1989-present. While many components are interchangeable between the two models, there are some differences in brake chamber sizes and slack adjuster lengths depending on your specific year and axle configuration. We recommend checking your VIN or contacting us with your truck's specifications to ensure proper fitment.

Are aftermarket brake drums and shoes as reliable as OEM parts?

The aftermarket brake drums and shoes we carry meet or exceed OEM specifications and are manufactured to DOT standards. Our premium brake drums are made from high-grade cast iron with proper heat dissipation properties, while our brake shoes feature heavy-duty friction material rated for commercial highway use. Many drivers report equal or better performance compared to OEM, especially with brands like Gunite, Webb, and Meritor that supply OEM manufacturers.

What tools and experience level are needed to replace drum brake components?

Drum brake replacement requires intermediate to advanced mechanical skills and specialized tools including a brake spring tool, drum puller, and proper jack stands rated for commercial trucks. The job typically takes 3-4 hours per wheel end for experienced mechanics. Critical steps include proper brake adjustment, ensuring correct shoe-to-drum clearance, and verifying air system operation. We strongly recommend professional installation if you're not experienced with heavy-duty brake systems, as improper installation can lead to brake failure.

How do I know when to replace drums versus just the shoes?

Brake drums should be measured for wear using a drum gauge. Replace drums when they exceed the maximum diameter stamped on the drum (typically when worn 0.120" over original diameter), show heat cracks, scoring deeper than 0.025", or have hot spots causing vibration. Shoes typically need replacement every 100,000-150,000 miles depending on application, but should be replaced anytime the friction material is less than 1/4 inch thick at the thinnest point or contaminated with oil or grease.

What's included in a complete drum brake rebuild kit, and what else might I need?

Our complete rebuild kits typically include brake shoes, springs, pins, bushings, and cam rollers for one axle. However, you may also need drums, slack adjusters, cam shafts, and air chambers depending on their condition. Don't forget brake cleaner, high-temp grease for cam tubes, and anti-seize for adjusters. Many customers also replace wheel seals and inspect bearings while the drums are off, as labor is already invested in disassembly.