Some felt that the M7 was too heavy so a M24 chassis was used. Standardized in November 1944. 448 were ordered.
Had drive sprocket in rear with individual torsion bar suspension. Had larger working space and storage space for ammunition than M7. It was powered by twin Cadillac engines. It had Hydra-Matic transmissions.
The 105 mm gun fired a 33 lb HE shell at a range of 12,200 yards.