Compared with the medium tank M4, the T23 featured a much lower box-type hull that lacked sponsons over the tracks. Stowage boxes line both fenders. The T23 was not accepted for service due to reasons of excessive maintenance requirements and the potential need to retrain maintenance personnel for its electric drive system, however its turret formed the basis of the 76mm gun turret seen on the M4 Sherman.
The drivers were each provided with a periscope in their hatch as well as one in the hull roof. The aperture for the rotoclone ventilator can be seen on the roof between the drivers.
The projection for the bow machine gun is shown here, and the weld lines for the various plates and castings that make up the glacis are also visible.
The T23 used the same vertical volute spring suspension as found on the M4 Sherman. This tank's suspension features the raised return roller arms that were intended to decrease wear on the track skids that was caused by steel track.
The drive sprockets were at the rear of the tank, obviating the need for a propeller shaft running through the fighting compartment.
Conversely, the adjustable idler was moved to the front. A large wrench was used to engage the hexagonal fitting and move the wheel in or out as needed.
The engine exhaust was routed through a port in the rear between the legs of the gun travel lock. A towing pintle could be installed centrally at the bottom between the two towing lugs, and the claw-like fittings all over the hull rear were for the stowage of a towing cable.
A closer look at the rear is provided in this image. Note that the hull rear is made up of two sections that came together under the center of the exhaust port.
The engine deck is shown here. The louvres closest to the camera were for air outlet, while those toward the turret were for air inlet. The left and right braking resistors and track driving motors were under the air outlet louvres, while the generators and GAN engine were further forward under the air inlet louvres. Stowage for the antiaircraft machine gun is provided on the turret bustle.
The air inlet louvres are shown here. The louvres were all hinged at the outside.
The lower rim of the turret features significant machining to allow it to clear various hull fixtures. The assistant driver's periscopes can be seen as well.
The GAN engine is seen here from the rear. Similar to the GAA of the medium tank M4A3 and GAF of the medium tank M26, it displaced 1,100in³ (18,000cm³) with a 5.4" (14cm) bore, 6" (15cm) stroke, and 7.5:1 compression ratio. It differed from the GAA by using two Stromberg Model HD-5 or HH-5 carburetors instead of the former's Model NA-Y5G carburetors; having an hydraulic electric instead of a mechanical governor; and mounting a special flywheel that acted as the driving plate for the propulsion generator. (Picture from TM 9-1731B Ordnance Maintenance--Ford Tank Engines (Models GAA, GAF, and GAN).)
A carburetor and the electric hydraulic governor are visible in this side view. (Picture from TM 9-1731B Ordnance Maintenance--Ford Tank Engines (Models GAA, GAF, and GAN).)
Designed for tracked vehicles, the Stromberg Model HH-5 was a dual horizontal carburetor with neither a choke nor power system. There was a single accelerating pump system that was actuated by a throttle valve plate shaft, and each barrel had its own metering and idle system. It was completely sealed: air used for venting the float chamber and for air bleeds was sourced from the air intake sleeves. A degasser assembly was present for each barrel; these would automatically shut off fuel to the idle system when the manifold vacuum was high. When the engine was turned off, an electric control provided positive shut-off of fuel. (Picture from TM 9-8625/TO 19-75CCA-7 Carburetors (Stromberg).)
The special flywheel of the GAN engine is visible at the top, and can be compared with the conventional flywheel found on the GAA engine in the center. (Picture from TM 9-1731B Ordnance Maintenance--Ford Tank Engines (Models GAA, GAF, and GAN).)
Though the 250 T23s built did not see active service, their direct descendant did. Fifty additional T23s were constructed with 90mm guns; ten of these were to be built with thicker armor and called T26. Further development and modifications including a more conventional powertrain and torsion bar suspension eventually yielded the T26E3, which was standardized as the M26 Pershing.
