105 mm M4 Howitzer Information Page
The M4 Medium with an M4 105mm Howitzer was a solution for a problem they didn’t know they had until the Italy Campaign. It turned out the M7 Priest did not work well in the direct fire role it was sometimes called to fill. The mount was not very accurate for direct fire, and there was no fixing it. It was also poorly suited to direct firework with its light armor.
The solution was mounting the 105mm gun in the M4 series. This required a rework of the gun and mount, but it was ready before the Normandy landings, and once in use, were well liked, replacing the M7 in Tank Company and Battalion 105 support roles.
All 105 Shermans were either M4s or M4A3, and all were built by Chrysler.