 --- --- ---
 --- --- ---
 --- --- ---
 ---  ---
 --- --- --- ---
 --- --- ---
The M3, Grant , Lee, and variations
The M3 is a direct result of the T5E2 which,
in experiments, had used a pack howitzer in the sponson position. The first M3 was built
at Rock Island Arsenal in mid March 1941 and by the end of that same month Baldwin Locomotive, Pressed Steel, Pullman Standard, Chrysler also known as the Detroit Arsenal, and GMC were gearing up to
start production. Designed with a 75mm, a 37mm and twin .30cal MGs, the tank packed a
nasty punch. The armor was riveted - but thick at up to 2 inches on the M3. Most were
built with the Wright radial engine but late models used a Continental. Some were even
fitted with the Guiberson model T1400 diesel engine. The diesel was never really adopted
for Army use, even though experiments were carried out, due to wartime needs by the Navy.
The diesel engine version was exported to GB. All sorts of conversions were tried and
applied including bridge layers, recovery vehicles, and self propelled guns. The M3 would
serve in at least a support role all during WW2 and is considered one of the most
important armored vehicles of WW2. Production ceased December 1942.
The M3 CDL: The Coast Defense Lights (CDL)
idea started sometime in 1942. The idea was then supposedly briefed to Eisenhower and his
staff in October 1942. From there, the Ordnance Board authorized production in February
1943. The M3 CDL tanks were assembled at Rock Island Arsenal. Instead of a main gun turret
the tank chassis mounted a steel box containing a 13 million candle power carbon arc lamp
backed by mirrors to focus the beam. A 10Kw generator was mounted on the back and run by a
power take off from the engine. The 75mm sponson gun was retained. Some 500 M3 CDLs were
produced in 1943-44. American Locomotive was contracted to reconfigure existing M3s. Press
Steel Car Company made the turrets. Arc lamps came from the Mole-Richardson Company. RIA
did the final assembly under tight security. They were referred to by several code words:
T10 Shot Tractor; Leaflet Tanks; Glamos. British called it the Cassock Project. There is a
report of an attempt to mount double CDL units on a M4 chassis but the outcome of this
experiment is unknown.
The following units participated in the tests at Camp Blouse in Arizona: 9th Tank Group
which consisted of the 710th Tank Battalion, 736th Tank Battalion, 738th Tank Battalion,
739th Tank Battalion, 740th Tank Battalion, 526th Armored Infantry Battalion (for
security), 554th Ordnance Heavy Maintenance Company (Tanks). Also appears there was 748th
Tank Battalion, 150th Station Hospital, 538th Ordnance Company, 166th Quartermaster and
629th Quartermaster.
M3 Production Apr. 1941 - Dec. 1942
| Detroit Tank Arsenal |
M3 - 3243
M3A4 - 109 |
| Baldwin Locomotive Works |
M3 - 295
M3A2 - 12
M3A3 - 322
M3A5 - 591 |
| American Locomotive Company |
M3 - 385
M3A1 - 300 |
| Pressed Steel Car Company |
M3 - 501 |
| Pullman Standard Manufacturing Company |
M3 - 500 |
Specifications - Remarks For
British In Red
| Crew |
6 |
| Weight |
Approx. 60,000 lbs. depending on the model |
| Length |
Approx. 18' 6" depending on the model |
| Width |
Approx. 10' 3" depending on the model |
| Height |
Approx. 10' 3" depending on the model |
| Engine |
Wright 973 radial 340hp though differences
occurred in some models. |
| M3 |
Riveted construction and side doors. 4942 M3
units were built including 600 special units known as "Lee" for the British. |
| M3A1 |
A limited production of 300 to test a cast
upper hull. Late models did not have side doors or a hull floor escape hatch. Used for
training only. |
| M3A2 |
A limited production of 12 (or 14 depending on
the source) to test an all welded upper hull with a cast turret. Used for test vehicles
only. |
| M3A3 |
Welded hull powered by twin GMC diesel
engines. 322 were built. Some went to the U.S.M.C. and the rest were sent "Lend
Lease". The M3A3 designation was later restricted to vehicles with welded hulls. |
| M3A4 |
Riveted hull powered by the Chrysler 30cyl
"Multibank". 109 were built. The hull
(including tracks and chassis) was increased to just over a foot longer to accommodate the
engine. No side doors. |
| M3A5 |
Riveted hull with no side doors on late
models. Powered by twin GMC diesel engines. 591 were built. Some went to the U.S.M.C. and
the rest were sent "Lend Lease". |
| Grant 1 |
The M3 with a turret designed
to British requirements. |
| Grant 2 |
British designation for M3A5
with original American turret. |
| Grant ARV |
British conversion of both the
Grant 1 and 2. Guns removed and a towing winch with an "A" frame hoist added. |
| Grant Scorpion 3 & 4 |
British conversion. A flail
type of minefield clearing device was fitted and the 75mm gun removed. An external motor
to drive the flail was added to the rear of the tank. Model 4 had two motors. |
| Grant Command |
British conversion. Additional
radio. Sometimes the guns were removed and replaced with dummys. |
| Grant ARV Mk. 2 |
Austrailian conversion of a
Grant into a recovery vehicle. |
| Grant CDL |
British conversion. A secret
weapon. The turret was removed and replaced by a armored searchlight with 13 million
candlepower. |
| Lee 1 |
British designation for the M3 |
| Lee 2 |
Designation for the M3A1 |
| Lee 3 |
Designation for the M3A2 (none
were delivered to the British) |
| Lee 4 |
Designation for the M3A3 with
a Continental engine. |
| Lee 5 |
Designation for the M3A3
(diesel) |
| Lee 6 |
Designation for the M3A4 |
British Specifications
| Model |
Fighting
Weight |
Length |
Height |
Width |
Hull |
Engine |
Performance |
| Lee 1 |
61,500 lbs |
18' 6" |
10' 3" |
8' 11" |
Riveted |
Wright |
21mph |
| Grant 1 |
62,000 lbs |
18' 6" |
9' 11" |
8' 11" |
Riveted |
Wright |
21mph |
| Grant 2 |
64,000 lbs |
18' 6" |
10' 3" |
8' 11" |
Riveted |
Twin
GMC
Diesel |
25mph |
|
