Abstract: A plate brake tester for testing the adequacy of the brakes of a vehicle includes first and second pairs of weight bearing plates, each sized to receive at least one wheel/tire assembly of a vehicle as a vehicle is driven over the plates. The first pair of plates are spaced from the second pair a predetermined distance along a predetermined direction of travel, which predetermined distance is substantially greater than the length of each plate as measured along the predetermined direction of travel. Sensors sense, for each plate, the brake force applied by a brake associated with the wheel/tire assembly passing over that plate and the dynamic weight of the wheel/tire assembly on each plate during braking. Control circuitry determines from the brake force and the directly sensed dynamic weight the adequacy of the brakes of the vehicle under test. Preferably, the first and second pairs of plates are approximately 30 feet apart along a test lane, and each plate is approximately 36" in length and 48" in width.