REPLACEMENT BULBS

Replacement Bulbs For Peterbilt Trucks

Burned-out bulbs are among the most common DOT inspection violations on commercial trucks — and one of the easiest to prevent with a stock of the right replacements on hand. Peterbilt trucks use a range of bulb types across exterior lighting, interior lighting, and instrument cluster applications, from standard incandescent wedge and bayonet bases to sealed beam headlights and LED-compatible sockets on newer models. We carry replacement bulbs for all common Peterbilt lighting applications so drivers and fleet shops can make quick repairs and stay compliant.

Frequently asked questions about replacement bulbs

What are the most commonly replaced bulbs on a Peterbilt truck?

Clearance and marker light bulbs are the highest-turnover replacement bulbs on most Peterbilts — they're exposed to vibration, heat cycling, and moisture and burn out regularly on high-mileage trucks. Tail light and brake light bulbs are close behind. Dash illumination bulbs and instrument cluster backlighting bulbs are also common replacements on older Peterbilt models, though newer trucks increasingly use LED backlighting that's less prone to failure. Carrying a small assortment of the most common bulb numbers for your specific model is a simple way to avoid a log violation for a burned-out marker light.

Can I replace incandescent bulbs with LED equivalents on a Peterbilt?

In most exterior lighting applications, yes — LED replacement bulbs that fit the same socket as the original incandescent are widely available for common Peterbilt clearance, marker, and tail light applications. LED replacements offer significantly longer service life and lower current draw. One caveat: on turn signal circuits using a thermal flasher relay, replacing incandescent bulbs with LEDs changes the circuit's current load and will cause hyper-flash — an electronic load-compensating flasher relay is required when converting turn signals to LED.

How do I identify the right replacement bulb number for a Peterbilt light?

The bulb number is typically printed on the glass envelope or base of the bulb being replaced. If the bulb is already burned out and unreadable, the Peterbilt parts catalog cross-references bulb application by model and lamp position. Most automotive and truck parts cross-reference guides also list bulb applications by vehicle. Common bulb numbers on Peterbilt trucks include the 1156 (single-contact), 1157 (dual-contact), 194 (wedge), and 921 (festoon), though specific applications vary by model year and light assembly.

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Shop lighting for Peterbilt trucks