When the US Army came to the realization that the new German tanks, Panthers and Tigers, were not only getting progressively tougher and deadlier, but were also becoming more numerous on the battlefield, they began to search for solutions to adequately deal with the threat. The 76 mm M1 gun was available and implemented onto their standard M4 Sherman tank, but the 76 mm firepower proved to be disappointing against the German tank armour. The search for a bigger gun was needed for the US tanks, and one solution was to simply add the turret of the developing M26 Pershing (then still known as T26) onto the M4 Sherman hull. The single prototype test in 1944 proved that the conversion could be done, however the overall project was cancelled once it was determined that the research and development time to test out the viability of the design in combat would not make the design come any faster than the newer M26 tank.

Introduced in Update "La Royale", the M4/T26 is a strange amalgamation of components from two tanks. On one hand, the T26 turret introduces the mighty 90 mm gun into the Sherman chassis, allowing better chances against more heavily armoured foes. On the other hand, all this is being performed on top of a M4 hull and components. Aside from the additional weight of the T26 affecting the tank body, the Sherman armour is no longer competitive against its opponents. In addition, the relatively tall Sherman hull raises the T26 turret higher than from the original M26 Pershing, so players need to be aware of accidentally exposing the M4 hull that would allow enemies with any sort of high-velocity cannon to quickly pierce through the Sherman's armour and knock out the tank. That said, players would benefit from their familiarity with the Sherman handling to continue playing as though they were the 76 mm armed version, with the 90 mm gun making even heavy tanks easy picking for the player.