The T30 75mm Howitzer Motor Carriage was an interim design produced in an attempt to provide the US Army with some self-propelled guns as quickly as possible. It was produced by mounting a M1A1 75mm pack howitzer on the back of a M3 Half-Track. Early production had the standard howitzer shield, later vehicles were given a more substantial armoured shield. None of the un-shielded T30s were used in combat.
The howitzer was mounted on a low table at the front of the fighting compartment, raising it above the driver's position. The half track's fuel tanks were moved into the rear corners of the compartment, with storage bins in front of them. Ammunition was stored in bins on the rear floor, and a machine gun was mounted at the centre-rear of the compartment.
The T30 was issued to armoured infantry regiments and to infantry divisions. The armoured infantry regiments got nine each, three for each battalion HQ. The infantry divisions had a cannon company armed with six T30 75mm Howitzer Motor Carriages and two T19 105mm Howitzer Motor Carriages.
Development of the T30 was authorized in October 1941 and it was accepted for production in January 1942. A total of 500 T30s were built during 1942 by the White Motor Car Company, with the first completed vehicles delivered in February 1942. The last 188 vehicles were returned to M3 standard before they were issued to the US Army. The T30 made its combat debut during Operation Torch, the Allied invasion of North Africa in November 1942. A small number of T19s and T30s were landed at Oran and Algiers to support the infantry that made up the bulk of the landing force. It was involved in the fighting in the Kasserine Pass in February 1943 and the more successful battle near El Guettar in March 1943.
The vehicle saw combat in North Africa, Sicily (where the half-tracked T30 was amongst the first artillery to land) and Italy, where it performed adequately, but it was phased out as soon as enough of the fully armoured M8 75mm Howitzer Motor Carriage became available. The infantry divisions lost their T30s after March 1943 when they were replaced with towed 105mm howitzers.