22-73952-000 Freightliner Cascadia Cab Extender Bracket, Short 2 3/8 in

The 22-73952-000BP is a direct replacement for OEM part 22-73952-000, the short lower cab extender bracket on the Freightliner Cascadia. It mounts at the factory locations with no drilling or modifications required.

The OEM 22-73952-000 is 40% glass fiber reinforced polypropylene, molded PPGF40 and marked REV B. The factory fit relaxes over time, and sustained road vibration drives the M6 nutsert against the thin fiberglass of the sleeper wall, enlarging the mounting hole until the fastener loses its grip. As the joint gives way, the cab extender panel shifts and resonates, and the aerodynamic seal between cab and trailer opens.

The 22-73952-000BP corrects the failure at the mounting interface. The mating surface is built up to a tighter tolerance, seating the joint solidly under torque and removing the clearance that allows vibration to take hold. It is rebuilt in carbon fiber reinforced plastic for strength and fatigue resistance beyond the original polypropylene.

A cab extender that has worked loose is not a cosmetic problem. Published aerodynamic testing places roughly 1% of fuel economy on every 10 inches of tractor trailer gap in highway service, and above approximately 30 inches each additional 10 inches adds about 2% drag. Gap fairings as a system account for roughly 7% drag reduction at 55 mph. A loose panel reopens that gap, and the loss is measured in fuel.

This is the short component of the lower mount, 2 3/8 in against 4 5/8 in for the long arm. The two differ by close to double in length and are not interchangeable. Works as a matched set with the long attachment arm 22-74370-000, or order both together as the lower cab extender bracket kit.