M4A1s "Grizzly" produced by Montreal Locomotive Works
Most of the information on this page is courtesy of Joe DeMarco. Note: some of the information on this page was compiled using a technique informally referred to as "counting heads." It is based on the ongoing study of period documents and photographs, as well as surviving Shermans. Due to the limited nature of available reference sources, some of the information presented here must be considered as "educated guesswork."

First of all, you have to identify the tank as being an M4A1(75) "small hatch" Sherman tank. Please visit this page to do so.

Montreal Locomotive Works manufactured 188 M4A1(75) "Grizzly" tanks from October to December, 1943.

86 M4A1(75) manufactured : Shop Number 1 / WD Registration No. CT-160194 through S/N 86 / CT-160279
102
M4A1(75) manufactured : Shop Number 87 / WD Registration No. CT-163911 through S/N 188 / CT-164012


Ram tank    M3 Lee medium tank

In the Fall of 1941, Montreal Locomotive Works began production of the Ram Cruiser Tank. The Ram was essentially an M3 Medium Tank with a new upper hull and main gun mounted in a revolving turret. This Canadian / British design corrected the major flaw of the M3 - the limited traverse of the sponson mounted 75mm gun. However, an unfortunate decision was made to replace the M3's 75mm with a British 6 pounder (57mm gun), mounted in a rather cramped turret. The Sherman, the US designed replacement for the M3 Medium, mounted a 75mm gun in a roomier 3-man turret. Ultimately all parties considered the Sherman to be superior to the Ram. In March 1942, only a month after the first production Sherman was built, the Canadians & British decided that Montreal Locomotive would replace the Ram in production with cast hull M4A1s as soon as conditions would permit. With the exception of Baldwin Locomotive, US manufacturers of the M3 Medium switched production over to the Sherman by mid 1942. In retrospect, had Montreal been able to switch to the M4A1 by mid 1942, it would have greatly aided the Allies, as Shermans were in high demand at the time. Ultimately, Ram production wasn't ended until July 1943 after 1950 units had been built. In that same month, it was intended to build 50 M4A1 Grizzlies, with 150 to be made each month thereafter up to February 1944. Due to various bureaucratic and industrial delays, Grizzly production didn't commence until October, 1943. By that time, Sherman production in the US was undergoing a drastic cutback. By early 1944, only three of the original ten Sherman manufacturers remained in the program, and they were building newer, improved, "second generation" models. Thus it is somewhat odd that Montreal Locomotive began producing a "first generation" model in late 1943. In any event, it was determined that US production would be sufficient to meet all Allied requirements for Shermans going forward, and Grizzly production was terminated in December 1943 after 188 units had been accepted. Left side photo courtesy of Paul and Lorén Hannah.


Ram cruiser tank

Montreal Locomotive Works sourced its Ram hulls from the General Steel Castings Corporation's Commonwealth Plant in Granite City, Illinois. The above photo shows a finished Ram hull at the Commonwealth facility in July 1942. The light spots that can be seen are casting imperfections that were filled in by welding. Note that the turret was mounted off center, and the turret ring diameter was 60 inches compared to 69 inches on the Sherman. The Ram's turret was smaller and lower than the Sherman's, which made for difficult working conditions for the crew.


M3 Lee medium tank

It would appear that MLW continued to source its hulls from General Steel when they switched over to Sherman production. Quite a few Grizzlies have survived, and every example we have examined has the distinctive General Steel logo (1) cast on the front. Years ago, this was labeled by some as the "Grizzly Badge," and thought to be a way to distinguish Canadian built M4A1s from those made in the US. However, approximately half of the cast hulls used by the Pressed Steel Car Company were also sourced from General Steel. Our research suggests that, aside from the T6 (Sherman) pilot, General Steel did not make any Sherman hull castings with direct vision. This may be because their early production capacity was taken up with Ram and M3A1 Medium Tank hull castings.


M4A1 Grizzly    M4A1 Grizzly

While it should not be assumed that surviving Shermans have their original components, weight of evidence suggests that all of the Grizzlies were built with D50878 "no pistol port" turrets cast by General Steel at their foundry in Eddystone, Pennsylvania. The serial numbers recorded from many of the Grizzly turrets indicate they were cast in the Summer of 1943. At that time, the turret molds were altered to eliminate the pistol port. The redesigned turrets also incorporated a cast in thickened cheek on the right front (indicated with the red arrow), which obviated the need for the "thin spot patch" applied to many earlier Sherman turrets. When the British became aware of the US Ordnance Department's "Eliminate the pistol port" directive in Spring 1943, they requested that their Lend Lease Shermans be exempt, since they found the pistol port to be a valuable crew asset, particularly for the loading of ammunition. Thus, one might expect that the Commonwealth planners would have sought to retain pistol ports on the turrets of the Grizzlies. However, the Canadians relied on a US supplier for their turrets, and those with pistol ports were no longer being produced by the time Grizzly production got underway.


M4A1 Grizzly    M4A1 Grizzly

US Ordnance documents have it that Montreal Locomotive sourced power trains for its Ram program from the Iowa Transmission Co of Waterloo. Examination of surviving Grizzlies suggests that all 188 units were built with Iowa power trains with 3-piece differential housings. The Ordnance Department had mandated that all new US produced Shermans would transition to the late, sharp nosed, 1-piece differential housing by September, 1943. Thus, the Grizzlies were the last Shermans to be made with 3-piece differential housings as original equipment. We suspect that the Grizzlies simply used up Montreal's remaining supplies of 3-piece housings after the termination of the Ram program. It is to be noted that Sexton production at Montreal continued into 1944. "Counting heads" on those, suggests that MLW completed the transition from the 3-piece to the late, 1-piece differential housing in early 1944.


M4A1 Grizzly    M4A1 Grizzly

The photos above show Grizzly Number 1, CT-160194, DND Number 75-988. This unit has survived and is on display in the UK at the Imperial War Museum, Duxford. Note the 13 tooth drive sprocket, indicating the use of US produced tracks. Many surviving Grizzlies, including the Duxford, were retrofitted with Canadian Dry Pin Tracks at some point during the course of their service. These were developed in mid to late 1943 in answer to the worldwide rubber shortage. CDP tracks were not interchangeable with standard Sherman track types, since their shorter pitch also necessitated production of a new 17 tooth drive sprocket. CDP tracks appear to have been installed as original equipment on Sexton IIs starting in the first quarter of 1944. The photos show a number of stowage items that were exclusive to the Canadian version of the M4A1, which we will describe going forward.


M4A1 Grizzly    M4A1 Grizzly

Grizzly Shop Number 25 is on display at the Bovington Tank Museum in the UK. In the US, the so called "Quick Fix" modification was mandated to be factory installed on Shermans starting in August 1943. Turret baskets were "skeletonized;" that is, the perforated sheet metal completely surrounding the turret basket was no longer installed, or was to be removed in the case of earlier production Shermans. The 75mm ammunition bins were encased in one quarter inch armor plates, and one inch plates were welded to the exterior of the hull to further protect the ammo bins. "Counting heads" suggests that all of the Grizzlies were built with skeletonized turret baskets and armored ammunition racks, but for whatever reason, Numbers 1 through 25 did not have the external armor plates installed.


M4A1 Grizzly    M4A1 Grizzly

The hull "appliqué" armor plates appear to have been factory installed starting around Shop Number 26. Montreal Locomotive (or its subcontractor) used standard rolled armor appliqué plates made to fit welded hull Shermans. They were then cut to fit the contours of the Grizzly. With 5 sections, the plate on the right front (1) seems rather elaborate, but is what is most commonly seen on surviving examples. Number 59 on display in Poland is the single unit we have encountered with a "record" 7 section plate.


M4A1 Grizzly    M4A1 Grizzly

Our "counting heads" method suggests that the last 70 or so Grizzlies were made with hull castings that eliminated the need for welding on the appliqué plates. These hulls are informally referred to as having "cast-in appliqué," and represent the final iteration of the small hatch M4A1. Lima Locomotive and Pacific Car and Foundry did not employ these late hull castings. They were introduced in mid October 1943 at Pressed Steel Car and mid November at Montreal. It is to be noted that the casting marks on General Steel hulls include dates, and the examination of a few "cast-in appliqué" Grizzly hulls indicate that they were produced August through October 1943.


M4A1 Grizzly    M4A1 Grizzly

The inclusion of the "Hatch in hull floor for anti-mine shackle gear" is described as one of the differences between Canadian and US built M4A1s. In theory, this permitted the bow gunner to emplace the Snake anti-mine device from within the protection of the tank. It is thought that Montreal Locomotive installed the hatches in most of their Rams and Sextons as well. Many surviving Grizzlies have been "remodeled" as US Army M4A1(75)s. The easiest way to tell that a surviving M4A1 is a Grizzly is to look for the additional hatch in the belly plate.


M4A1 Grizzly    M4A1 Grizzly

Another difference between Canadian and US built M4A1s, is that the Grizzlies were equipped with stowage boxes on their turrets in the manner of many British tanks. These were "to hold blankets, greatcoats and ground sheets."  We suspect the engine crank may have been stored in the box as well (it has been seen on a surviving example), since we have been unable to find the fittings for it on the tank's exterior. Only the variant shown on the left above, with the additional external tarp fittings, is seen in the few available period photos. The simpler version on the right is more prevalent on surviving Grizzlies. In fact, Grizzly Number 1 was retrofitted with the simpler box. It may have been introduced later in production, or as a post production replacement. Both pictures courtesy of Paul and Lorén Hannah.


M4A1 Grizzly    M4A1 Grizzly

The arrangement of the pioneer tools on the right side of the Grizzly was the same as on the US M4A1. Unlike the US model, no tools were stowed on the upper rear hull plate. On the left side, the shovel's orientation was reversed, and the track tensioning wrench and sledge hammer were located alongside the shovel. The Canadians also added 6 tie downs (circled) on the left side. These are shown holding a camouflage net on the original Grizzly stowage model (inset). An engine crank handle was a standard tool on M4s and M4A1s, but, as mentioned previously, we cannot find fittings for it on surviving Grizzlies.


M4A1 Grizzly    M4A1 Grizzly

Two 5 gal water cans were stowed on the left side in the fighting compartments of US built M4A1s. Canadian documents mention that "Six two gal. cans are stowed in place of two five gal. cans." This may have been the case, but, in a few period photos, including Grizzly Number 1, a pair of 5 gallon "Jerry" cans are shown stowed horizontally on the upper rear hull plate. The jerry can fittings have been removed from most surviving Grizzlies, and only tell tale weld scars remain. Grizzly Number 65, the Canadian Firefly pilot, is perhaps the only remaining example that still has the fittings. Sexton IIs also carried a pair of jerry cans (upright) in the rear. Left side photo courtesy of Don Allen.


M4A1 Grizzly

The inclusion of only 2 Methyl Bromide type fire extinguishers is mentioned in the official docs. "2 of these carried in brackets on the exterior of hull at the rear." However, the examination of surviving Grizzlies shows that 4 fire extinguisher fittings were provided, which suggests that the tanks were actually equipped with 4 extinguishers. Grizzly Number 1 shown earlier, can be seen to have the 4 fittings, but only 2 extinguishers are mounted in the rear, directly behind the air scoops. The two additional fittings, on each side in the center, are empty. In the undated photo of Grizzly Number 46 above, fire extinguishers can be seen mounted in both the rear and center positions (circled). In this photo, one can also see the jerry can fittings (1), round air cleaners (2), the "stub" of the trailer towing pintel (3), and the original type M4 / M4A1 exhaust deflector in the "closed" position (4). The configuration of the tail light guards is similar to that of Pressed Steel Car.


M4A1 Grizzly    M4A1 Grizzly

Grizzlies were built with a mix of newer and older features. The gun travel lock (1), and the position of the siren (2) can be considered late 1943 features. Periscope guards (areas circled in red on the left side photo) were introduced on the Sherman at about the same time, but were not factory installed on the Grizzlies. Weight of evidence suggests that most or all were equipped with the round type of Vortox air cleaners. Standard US type trailer towing pintels were installed, but these appear to have been removed from most surviving examples, leaving only weld scars. A curved sheet metal exhaust deflector was installed on US built M4s and M4A1s starting in early 1943, and the associated fittings for these can be seen on a few surviving Grizzlies (areas circled in red on the right side photo). Most US built M4s and M4A1s had stops fitted to prevent the engine access doors from damaging the air cleaners, but surviving Grizzlies don't show evidence of these.


M4A1 Grizzly    M4A1 Grizzly

Grizzly turrets also show a mix of new and old features. The inclusion of the 2 inch smoke mortar (1) was listed as a difference between the Grizzly and the US M4A1, but it was introduced on Shermans starting in the Fall of 1943. Modification kits were also provided for retrofit to older tanks. The "Commander's Vane Sight" was introduced at about the same time as the smoke mortar. However, evidence suggests that Grizzlies were only produced with the original blade sight (2). Grizzlies appear to have been built with the older M34A1 Gun Mount featuring lifting rings and the exposed flange on the right (3). An improved type of commander's split hatch, with integral hatch springs, became available to Sherman production around November 1943. However, Grizzly production seems to have ended with the original type of split hatch (4). The majority of surviving Grizzlies were retrofitted with the commander's vision cupola. These must have been added in the postwar years, as they were in high demand for fighting Shermans right up to V-J Day in September, 1945. The situation is quite the opposite now, with restorers seeking the split hatches, since they more accurately reflect the WW II appearance of most "first generation" Shermans like the Grizzly.


M4A1 Grizzly

In the absence of proper documentation, we can only present our educated guesses concerning the various aspects of the factory installed suspension components. Grizzly Number 1 shown earlier can be seen with 1943 type US produced bogies with straight return roller arms. We believe these would have been standard on all of them. Original equipment road wheels would have been either the welded spoke, as seen on Number 1, or the "disc type." In the US, the welded spoke idler seen on Number 1 was mandated to be replaced with the "disc type" on all Shermans starting in May 1943. Number 1 can also be seen with the M3 type drive sprocket. However, we think that Montreal equipped most units with the "plain" sprockets (1) and "disc type" idler wheels (2). There is no mention of the use of non standard tracks or sprockets in the Liaison Letter sent to the US describing the differences between the Grizzly and the US M4A1. We would judge that the suspension components on Number 6 shown above represent the "as built" appearance of the majority of Grizzlies.


M4A1 Grizzly    M4A1 Grizzly

Many surviving Grizzlies can be seen with Canadian produced bogie brackets. These were cast by the Dominion Steel Foundry and carry Part Number C40571. They are more substantial than the standard US D47526 bogie, and are said to have been designed to better absorb the recoil of the Sexton's 25 pounder gun. It is thought that they, along with the CDP track, became available to Sexton production in the first quarter of 1944. We would guess that spares from the Sexton program were retrofitted to Grizzlies and other Shermans in Canada in the postwar years. In the left side photo, note the larger "ribs," and the pair of "hollows" at the top. In the right side photo, a standard US produced bogie can be compared with the Canadian type mounted behind it. An examination of the Canadian bogie brackets shows that "MLW" was stamped into them at the top, as shown in the inset. Photos courtesy of Jim Goetz.


M4A1 Grizzly    M4A1 Grizzly

The interiors of US built Shermans were painted white, while Grizzlies appear to have been painted silver (above, left), as in British built tanks. The British No. 19 Radio (above, right) was, of course, installed as standard equipment. In the RAM and Sexton, the driver's position was on the right, to British preference, but remained on the left on the Grizzly.


M4A1 Grizzly

At least 4 surviving examples have been noted to have fabricated air scoops (above, left). They are uniform in appearance, which leads us to think that they were made in house, possibly because Montreal Locomotive was unable to obtain 188 pairs of the standard castings (above, right). MLW had some prior experience with the fabrication of air scoops, since they were introduced as a modification on late production Ram IIs.


M4A1 Grizzly    M4A1 Grizzly

Another bit of minutia concerns the rearward cable clamp. The vast majority of US produced M4A1s can be seen with the rear cable clamp mounted parallel to front one. We've noted that the surviving Grizzlies have the rear clamp oriented in the opposite direction. This may have been decided by a coin flip, or possibly was done because the shovel's position (1) was reversed and a fire extinguisher (2) was mounted near the clamp. Perhaps the tow cable "fit better" around these objects using the MLW orientation? Right side photo courtesy of Don Allen.


M4A1 Grizzly    M4A1 Grizzly

A "groove" is seen in the center rear of the hulls of surviving examples. This was once referred to as the "Grizzly Groove," but in fact, is a feature of all small hatch M4A1 hulls cast by General Steel. Continental Steel castings did not have a groove, and it was discontinued by General Steel when the change was made to the production of large hatch M4A1(76) upper hulls.


M4A1 Grizzly

In March 1943, the Canadians began development work on "a 4-gun 20-mm A.A. tank" to be based on the Grizzly chassis. Exactly one year later, trial work was completed, and the "Skink" design was released to production. It was intended to produce 265 units from July through December 1944, but in April 1944, the order was cancelled, because the Allies had gained air superiority in Europe. Ultimately only 3 pilot units were completed. One was sent to the UK for trials, and afterward was transferred to the ETO with a demonstration unit. While it never fired at enemy aircraft, it was reported to have participated in ground combat in 1945. Note that the Skink sent to Europe (shown above) was outfitted with sand shields and CDP tracks. Like standard Sherman steel tracks, CDPs were "not as easy on bogie tires as rubber block types." This might explain the mix of road wheels that can be seen.


M4A1 Grizzly

The Skink pilot seems to have been the only Grizzly based unit sent overseas during WW II. The others appear to have been used as training tanks in Canada into the post war years. Many of them, along with some Sextons, were sold to Portugal in the 1950s. When they became obsolete, Portugal sold them to collectors, and hence an unusually high number of Grizzlies and Sextons have survived. Grizzly Number 65 remained in Canada, and has an interesting history. The British sent Firefly turrets to both the US and Canada "in the Winter of 1943-44." The British did not consider the M4A1 to be a suitable platform for the 17 pounder conversion, because the contours of the cast hull could not accommodate the standard Firefly internal stowage arrangement. However, in recent years, Number 65 was opened and examined, and it has been reported that the Canadians actually did manage to reconfigure the interior and convert the tank to a Firefly. Photo courtesy of Don Allen.


M4A1 Grizzly    M4A1 Grizzly

General Steel small hatch hulls have been seen to have the caster's data on the underside of the hull between the left air cleaner and the exhaust pipe (circled in red). These markings are often obscured by a blanket of oily, sooty dirt, but we have been able to record them from a few surviving examples. The standard part number of the small hatch upper hull casting is E-4153 as seen in the right side photo. This particular hull was manufactured in 7-43 (July), and was Serial Number 1712. The "- C" behind the date indicates that the hull was cast at General Steel's Commonwealth Plant in Granite City, Illinois. The Grizzly in this example was accepted in November, 1943 and was one of the last units made with welded on appliqué. The E-4153 info can be seen on the firewall facing the fighting compartment of upper hulls cast by Continental Steel. General Steel relocated the casting info to the firewall when they began producing large hatch hull castings.


M4A1 Grizzly

An item of minutia regarding small hatch upper hulls cast by General Steel is that approximately half of them used an alternate, but official, part number - D-53275. This has be seen, minus the "D" prefix, as often as E-4153 on surviving examples. Our examinations haven't discovered any discernable differences between the two hull castings. Chris Hughes was able to photograph the casting data from Shop Number 43 of the Military Vehicle Technology Foundation. This particular hull was manufactured in 4-43 (April), and was Serial Number 1169. There was quite a lag between the time the hull was cast, and Grizzly #43 was accepted in October, 1943, but MLW had intended to begin production in July, and no doubt began ordering components before that. Anything dated has research value, so should any readers see these markings on any surviving M4A1(75)s with the General Steel logo, we would greatly appreciate a report.


M4A1 Grizzly    M4A1 Grizzly

As best we have been able to determine, Grizzlies were the only M4A1s that had the tank's Serial Number, or "Shop Number" in Canadian parlance, factory stamped anywhere on the exterior of the hull. The Shop Number was struck below the General Steel logo on the front, such as can be seen on Number 6 above. An original Grizzly dataplate is shown on the right. Note that the Shop Number is not listed on the dataplate. The "Serial Number" stamped in the upper right was actually assigned by the British War Department; in this case, it is 160199. The WD Number was painted on the side of British / Commonwealth tanks with a "T" for "tank" prefix included. In general, tanks in Canadian service had a "C" painted on in front of the "T-Number."  There is a mathematical correlation between the Shop Number and the "CT-Number" on the Grizzlies. So, for instance, CT-160199 corresponds to Shop Number 6. Grizzly dataplates also have a "Department of National Defense, Canada" or DND Number stamped in the lower left of the dataplate, along with the year of manufacture stamped in the lower right.

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