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Knox Trailers · Electrical & Lighting
TRU40756
In stock · ships from Knoxville
This is a left-hand (roadside) light box assembly for heavy-duty trucks and trailers.
Confirm the part fits before you buy. Applications and interchange numbers are researched and audited per part.
We don't publish fitment for this part yet. Rather than guess, get it confirmed against your truck in under a minute.
It combines two 4-inch round red incandescent lamps for stop, turn, and tail functions, along with an integrated side marker clearance light and a reflector. The unit is housed in a steel enclosure with a black PVC trim face and mounts via a bracket for universal fitment. Replace this assembly when your existing rear light module is damaged, corroded, or fails to meet DOT lighting requirements.
Part Number: TRU40756
LIGHT BOX ASSY LH
Unit: ea
Dealer: Knox Trailers
Compatibility, alternatives, and more
Parts commonly needed alongside electrical & lighting
