The M332 Trailer Replaced the M10 Ammunition Trailer from WW2, originally designed to be towed behind amour to allow extra ammunition to be carried into battle, It was found to be unpopular because it hampered the manoeuvring of the tow vehicle. During the Vietnam War its was mainly used for the transportation of Ammunition to and from Artillery Firebases. The M35 or M54 were the main tow vehicles.

The M332 Ammunition Trailer is a cart-type, 1 1/2-ton, 2-wheel trailer, a larger and heavier replacement for the M10 Ammunition Trailer. The M332 Ammo Trailer carries 12 complete 8-inch rounds, twenty-four 155-mm rounds, and fifty 105-mm rounds.

Some of the characteristics of the M332 Ammunition Trailer are:

Open-frame trailer chassis with ammunition cargo compartment and fuse cap container mounted on frame.

Two-wheel single axle with leaf spring suspension

Retractable landing leg to support front of trailer when uncoupled from towing vehicle

Air-operated hydraulic brake system controlled from towing vehicle

Manually operated parking brakes

24-volt electrical system

Automatic emergency braking in event of trailer breakaway or emergency air line break

Trailers may be connected to each other in tandem and towed by a 5-ton truck, at speeds not greater than 10mph