Truck-Lite 40001Y 40 Series 4" Round Yellow Incandescent Rear Turn Signal Kit (12V, 1-Bulb, Black Grommet Mount, PL-2, Stripped End/Ring Terminal)

Get reliable signaling and high-visibility safety with the Truck-Lite 40001Y (Model 40) 4-inch round yellow incandescent rear turn signal kit. Designed specifically for heavy-duty commercial trucks, trailers, and utility fleets, this all-in-one kit includes everything you need for a fast flush-mount installation. It features a heavy-duty, shock-mounted single-filament bulb to significantly extend lamp life by mitigating road vibration, housed within a sonically sealed polycarbonate lens and housing.

All-In-One Signaling Solution

The Truck-Lite 40001Y 40 Series kit takes the guesswork out of turn signal replacement. By combining a premium, impact-resistant yellow round lamp with a tight-fitting black PVC grommet and a PL-2 plug, this kit provides a complete out-of-the-box solution for commercial trucks, step vans, trailers, and vocational vehicles. The included grommet is designed for flush mounting in any standard 4.5" hole.

Built to Absorb Real-World Road Shock

One of the most common causes of incandescent light failure is filament breakage due to constant road vibration. Truck-Lite tackles this issue head-on with its signature shock-mount technology. The Model 40 bulb base is specifically cushioned to absorb vertical and lateral impacts, meaning fewer bulb replacements, less fleet downtime, and reliable operation on rugged routes.

Reliable Weatherproof Construction

Engineered for the demanding environments of transport hauling, the 40001Y features a sonically welded polycarbonate housing and lens. This seamless weld locks out moisture, corrosive salt spray, and road grime that typically lead to socket corrosion. Combined with the stripped-end and ring terminal wiring harness, this kit ensures a secure electrical connection that stands the test of time.