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Description
Due to the success of the M4A3E2 Sherman 'Jumbo' assault tank of Fall 1944, it highlighted the need for greater armor protection. 7 December 1944, Army Ground Forces (AGF) recommended that the Ordnance Department modify the new M26 Pershing medium tank with heavier armor and Army Services Forces directed that immediate action be taken.

The first approach was a Pershing with thicker armor with a lower final drive gear ratio to maintain a reasonable level of mobility. This was the then T26E5 heavy tank, now T26E5 medium tank. The second approach was a new tank utilizing as many Pershing components as possible. OCM 26606, 8 February 1945, recommended the construction of 4 pilot vehicles and designated them as heavy tank T32/T32 heavy tank. Formal approval for the project as recorded in March [1945].

The design was marked as high priority basis and the mock-up was completed 10 April 1945. The Ford GAC V12 engine and cross drive transmission of the T29 heavy tank was incorporated into the T32 heavy tank design. The T32 heavy tank had one extra roadwheel compared to the Pershing, bring it up to 7 per side. It was armed with the high velocity T15E2 90mm Gun with a single .30in cal machine gun as the coaxial. The T15E2 90mm Gun used separated ammunition and fired the 24 pound AP (Armor Piercing) T43 shot at 3200ft/s and the 16.7 pound HVAP (Hypervelocity Armor Piercing) T44 shot at 3750ft/s. Frontal hull armor was 5in at 54 degrees and using this equation:

TL [Line-of-sight/LOS thickness]=TN [normal or actual thickness]/cosine(theta [angle from vertical])
TL=127mm/cosine(54)
TL=216.0653053=~216mm or ~8.5in

It had 8.5in of effective armor due to the cosine rule.
The turret front had a thickness of 11.75in or 298.45mm to 6in or 152.4mm on the turret rear. The first two pilots, 1 and 2, was cast and had a bow mounted .30in cal machine gun for the assistant driver. Pilots 1 and 2 were completed 15 January and 19 April 1946 with both shipped to Aberdeen Proving Ground. The T32 heavy tank was the first vehicle with a cross drive transmission to be tested at both Aberdeen and Fort Knox. The EX-120 cross drive transmission had many teething problems as expected, but led directly to the CD-850 series of cross drive transmissions that became the standard of American tanks.

Description
Due to the success of the M4A3E2 Sherman 'Jumbo' assault tank of Fall 1944, it highlighted the need for greater armor protection. 7 December 1944, Army Ground Forces (AGF) recommended that the Ordnance Department modify the new M26 Pershing medium tank with heavier armor and Army Services Forces directed that immediate action be taken.

The first approach was a Pershing with thicker armor with a lower final drive gear ratio to maintain a reasonable level of mobility. This was the then T26E5 heavy tank, now T26E5 medium tank. The second approach was a new tank utilizing as many Pershing components as possible. OCM 26606, 8 February 1945, recommended the construction of 4 pilot vehicles and designated them as heavy tank T32/T32 heavy tank. Formal approval for the project as recorded in March [1945].

The design was marked as high priority basis and the mock-up was completed 10 April 1945. The Ford GAC V12 engine and cross drive transmission of the T29 heavy tank was incorporated into the T32 heavy tank design. The T32 heavy tank had one extra roadwheel compared to the Pershing, bring it up to 7 per side. It was armed with the high velocity T15E2 90mm Gun with a single .30in cal machine gun as the coaxial. The T15E2 90mm Gun used separated ammunition and fired the 24 pound AP (Armor Piercing) T43 shot at 3200ft/s and the 16.7 pound HVAP (Hypervelocity Armor Piercing) T44 shot at 3750ft/s. Frontal hull armor was 5in at 54 degrees and using this equation:

TL [Line-of-sight/LOS thickness]=TN [normal or actual thickness]/cosine(theta [angle from vertical])
TL=127mm/cosine(54)
TL=216.0653053=~216mm or ~8.5in

It had 8.5in of effective armor due to the cosine rule.
The turret front had a thickness of 11.75in or 298.45mm to 6in or 152.4mm on the turret rear. The first two pilots, 1 and 2, was cast and had a bow mounted .30in cal machine gun for the assistant driver. Pilots 1 and 2 were completed 15 January and 19 April 1946 with both shipped to Aberdeen Proving Ground. The T32 heavy tank was the first vehicle with a cross drive transmission to be tested at both Aberdeen and Fort Knox. The EX-120 cross drive transmission had many teething problems as expected, but led directly to the CD-850 series of cross drive transmissions that became the standard of American tanks.