105mm Gun T8 was an anti-tank gun developed in the United States in mid-1940s. The prototype for this gun was the German 88 mm Pak 43/41 anti-tank gun captured by the U.S. Army in France. The development started in October 1944; the gun reached trials in February 1946. Soon afterwards the project was cancelled.
In December, 1942, Allied forces reported that new German armored vehicle designs were resistant to 57 mm anti-tank guns, the largest anti-tank gun available. The US Ordnance Department began preliminary studies on a gun design similar to the German 88 mm Pak 43/41 anti-aircraft gun which was then successfully being used as an anti-tank gun. The first proposal was a combination of the 90 mm M1 Anti-aircraft gun mated to the M2 recoil mechanism from the M2A1 105 mm howitzer. The example was designated 90 mm anti-tank gun T8 on carriage T5.
The T5 gun carriage proved unacceptable due to structural weaknesses found while towing off-road. After two redesigned carriages were tested, the T5E2 was classified as limited standard. After additional trials at Aberdeen Proving Grounds, the T8 gun was found to be too heavy. Alternative carriages were tested, with no carriage found acceptable.