shows the very first M4A2 - the pilot tank as produced by Fisher Body
(Serial Number 2305, accepted in April 1942). It is believed that the
50 first units produced by Fisher were similar to this one. This
variant was based on the design concepts of the M4 welded hull pilot
constructed at Rock Island Arsenal in October, 1941. The pilot used the
M3 Medium Tank lower hull, power train, engine & running gear.
The upper hull of the RIA pilot utilized various cast components
plugged into the basic assembly of welded together armor plates. These
castings included the drivers' hoods, antenna bracket, bow &
fixed machine gun "plate," hull ventilators, and a bullet splash guard
around the turret, to name a few. The M4A2 Pilot closely followed the
RIA design, although, of course, it substituted the GM Twin Diesel
Power Plant for the original Wright Radial engine.
The two photos above show several items that
are specific to very early Fisher built, small hatch M4A2s. On the
left-side photo circled in red, from left to right, the cast antenna
bracket and the crude "bent rod" lifting ring, the cast bow &
fixed machine gun "plate," the cast drivers' hoods with direct vision
slots, the other "bent rod" lifting ring, and the siren affixed to the
mudguard. The right-side photo shows the construction of the front
glacis with the red lines indicating the weld joints. Note that the
"plate" that includes the bow mg and twin fixed machine guns was
actually a casting, whereas the other sections of the glacis were armor
plates. The twin fixed machine guns were eliminated from the design in
March, 1942, even before the first M4A2s rolled off the assembly lines.
However, Fisher already had a number of units "in the pipeline," and
only they manufactured a few M4A2s with the fixed machine guns
actually installed. Subsequent units had the mg apertures welded up,
until the original bow casting was modified to eliminate them.
left side photo above shows a rear view of the Fisher Pilot. Due to a
critical shortage of casting capacity at US foundries, Fisher Body
pioneered the use of fabricated substitute components ("fabricated"
means building a component from smaller parts shaped and welded
together). Note that the Pilot's rear turret splash is fabricated, no
doubt the first such component they made. This part has only been seen
on 1942 production Fisher M4A2s. The other builders and later Fishers,
used a cast part.
The right side photo shows the fourth Fisher built M4A2, S/N 2308.
Buick, another division of General Motors, began making power trains in
early 1942. From the outset, the factory constructed their units with
the recently designed one-piece (E4186) differential cover, a great
improvement over the three-piece differential of the M3 Medium. S/N
2308 was used to test one of the first Buick power trains The M3 type
bogie units as seen on 2308 were seriously overtaxed by the
Sherman, and sufficient supplies of both the M4
bogies and power trains with one-piece diffs became available
so that Fisher was able to complete the transition to them by August,
1942. An odd feature of 2308 is the white painted hatch interiors. No
doubt they would have been repainted in Olive Drab, if the tank had
ever been sent overseas.
Starting in June 1942, Fisher began to
substitute fabricated components for parts that had previously been
cast. Early units continued to employ the cast drivers' hoods with
direct vision. Weld joints were a ballistic weak spot, & the
glacis pattern was simplified somewhat by the use of a single piece of
armor plate across the lower front. A fabricated bow machine gun socket
was welded into this plate. Other fabricated parts introduced included
the antenna bracket, the headlamp sockets, and the various sections of
the turret bullet splash guards.
Close up examples of these components are shown below...
antenna bracket that replaced the casting used on the first fifty or so
Fisher M4A2s. Note the sharpness and the distinctive "D" shape.
Two views of
the fabricated bow MG socket. These and the fabricated antenna brackets
were also used for a short time on some M4A2s made by Pullman Standard,
as well as on nearly the entire production of Shermans manufactured by
Baldwin Locomotive Works.
A comparison of the "fabricated" head lamp
sockets versus the cast sockets used by most other manufacturers. The
fabricated sockets were also standard on 47 degree hull Shermans.
bullet splash guard sections were fabricated from armor cut and bent to
shape where needed. These appear to have been exclusive to Fisher built
M4A2s. As far as has been observed, all the other builders used cast
turret splash sections, which often have a nomenclature part number
cast in them (circled in red).
The rear section of the
turret splash guard
has been fabricated into two variants, the 1st one ("straight" version)
being the earliest, soon replaced with the more usual "bent" rear
The rear turret splash, in
front of the engine deck doors, was fabricated on the earliest M4A2s,
including the Pilot. It is thought that in early 1943, Fisher switched
over to the cast piece that was used from the start by the other M4A2
Note also that by September 1942, in the interest of simplifying,
Fisher had lowered the number of bolts securing the rearmost engine
deck plate from 11 to 6.
Another new part introduced
at this time is informally referred to as the "padded" hull lifting
ring. These were castings with rectangular bases. They were also used
by most of the other manufacturers, although they transitioned to the
most common type of cast lifting rings (without the rectangular pad) in
early 1943, while Fisher continued to use the "padded" ones until the
beginning of 1944.
The direct vision slots
were considered ballistic weak spots, and in late 1942, Fisher Body
dispensed with them when they transitioned to fabricated drivers' hoods
with an additional periscope in front of the drivers' hatches. Note the
very sharp, angular appearance of the welded together drivers' hoods
(right side photo). Fabricated drivers' hoods were exclusive to
Fisher-made M4A2s. The other builders used castings.
Here is shown the little
bullet splash protecting the drivers hoods hinge knuckles (circled in
red on the photo). This part has been seen on some Fisher &
ALCO Shermans. It was an official part that seems to have been
introduced in mid 1943. The reason this part was not added to other
manufacturers' Shermans is unknown.
Fisher M4A2 fabricated
hoods as seen on SN 26830. The hoods used the same cast hatches as all
other small hatch Shermans. The periscope guards (circled in
red on the left-side photo) were introduced at Fisher in Sept 1943,
& Tank Depots were directed to install them in the succeeding
months as supplies became available to them.
Positive hatch lock mechanisms with equilibrator springs (circled in
red on the right side photo) were also added to Fisher Shermans in mid
1943. These made the hatches easier to manipulate, and insured that
they were locked in the open position, thereby avoiding injury
to the crew. Aside from factory installation, modification kits were
provided for retrofit by Tank Depots or "in the field."
the Government mandated a change "without obsolescence," there were
generally transition periods where the older parts were used up, even
as the new parts were introduced into production to eventually replace
the older parts. Thus, one might see a Sherman with direct vision that
was made AFTER one with fabricated drivers' hoods. The chart above
shows the evolution of the M4A2, including the transition from the
multi-part to a simpler & more ballistically sound single plate
authors don't know of any surviving M4A2s with transitional pattern 2
it can be seen above on this USMC Sherman. An
M4A2 with the transitional pattern 3 has been discovered in Chieti,
Italy. It has Serial Number 8514 and was built in December,
Fisher and most of the
other manufacturers used what are informally referred to as "narrow"
drivers' hoods on their small hatch Shermans. Only Ford &
Chrysler used "wide" drivers' hood castings on their M4A3 and M4A4s.
The lines in red in the pictures above show the welds on the front
glacis. Left-side picture courtesy of Paul Hannah.
photo shows a late Fisher M4A2 Sherman (Serial Number 26875, built in
July 1943), as displayed at Carrefour
de la Croix de Médavy, France. This tank has
fabricated drivers' hoods and the sharp nosed differential cover (part
number E8543); instead of the earlier, more rounded one piece
differential cover (part number E4186). It is thought that July 1943
was indeed the transition point for the introduction of the E8543
differential cover at Fisher.
Originally, these diff. covers had cast in steps (by the towing lugs),
but they interfered with the newly introduced quick release towing
shackles, & the cast steps were soon replaced with metal
strips, such as are on the Médavy (for more information,
have a look to this
Fisher built Shermans have the Tank's Ordnance Serial Number
stamped into the rear towing lugs, it can also be found inside
the dataplate frame, beside the driver's position.
From the beginning of the M4A2 production at Fisher, the Ordnance
Serial Number was stamped on both tow lugs of the differential housing.
Starting around July 1943 and the introduction of the E8543
"sharp nose" differential cover, Fisher Body stamped the serial number,
an "S," on both edges of the part.
Fisher built Shermans have also been seen to have a loose
build sequence number stamped on the left front (driver's side)
The authors would gladly receive
such production data information from any readers who encounter a
surviving Fisher built Sherman.