History: In January 1938, Krupp-Gruson received an order to produce 200 in the 4th Series BW and 48 in the 5th Series. Of this total, only 229 were completed as gun-armed Pz Kpfw. The other 19 chassis were utilized to produce 16 bridge-laying tanks, 2 self-propelled guns and a Munitionsschlepper for Karl. Later in 1941, in an endeavour to seek a more powerful armament, an Ausf D was rebuilt with a 5cm KwK39 L/60.
Specific features: The main improvements incorporated in the Ausf D were the increase in the side and rear armour from 15 to 20mm, and the provision of an external mantlet for the 7.5cm KwK. The superstructure front was stepped so that the plate in front of the radio operator was farther back than that in front of the driver. The driver had a pistol port to the right front, and the hull MG was reintroduced in front of the radio-operator. Ausf D, produced late in the series, had additional 30mm plates bolted and welded to the superstructure and hull front, and 20mm plates bolted to the hull and superstructure sides. Later, in 1943, several Ausf D were refitted with 7.5cm KwK L/48 for use with training and replacement units.
Combat service: By May 1940, Pz Kpfw production had been sufficient for every tank detachment to have a medium tank company of from six to eleven pz Kpfw IV. On 10 May 1940, at the start of the campaign in France, there were 280 Ausf A, B, C and D in the Panzer divisions. The Ausf D saw service in France, the Balkans, Africa and Russia. The last few were phased out by attrition early in 1944.
History: In January 1938, the order for 223 6th Series BW was issued to Krupp-Gruson, and this total was completed.
Specific features: The main improvements introduced with the Ausf E were a new cupola design, modifications to the turret, and increased armour protection. The turret now had a single bent plate for the turret rear, and an exhaust fan to extract gun fumes. While all Ausf E had a 50mm hull front and 20mm plate bolted to the hull and superstructure sides, several of the early Ausf E were minus the extra 30mm plate on the superstructure front. Minor modifications included a simplified sprocket design, glacis hatches countersunk level with surface of glacis, new design of driver's visor (pivoting), single signal post on turret roof and an armoured cover for the smoke-candle rack.
Combat service: With the continued production of the Ausf D, and the completion of the Ausf E, sufficient Pz Kpfw IV became available to furnish each medium tank company with ten Pz Kpfw IV for the campaigns in the Balkans, North Africa and Russia. Forty Ausf D and E were taken to North Africa with the 5th and 8th Panzer Regiments, and 438 Ausf B-F were with the seventeen Panzer divisions which attacked the Russians in June 1941. The last Ausf E were phased out by attrition early in 1944.