Sherman tracks end connectors

End connectors for Vertical Volute Spring Suspension (VVSS) tracks
Introduction : A Sherman track is made of shoes. A shoe is an assembly of one link, two connections (a.k.a. end connectors), two wedges and two nuts. The track link pins were connected by means of end connectors which were held in place by a bevelled wedge nut. The nut is part number 503330 and the wedge is part number A176090. Because of this slight bevel the track links were forced to curl inward. The end connectors were made of cast steel with integral guide horns. There were at least three standard end connector types. They come in two basic shapes, one with a narrow guide horn (for 1-1/8" and 1-1/4" diameter pins) and one with a wide guide horn (1-1/4" diameter pins). The standard end connectors can be seen with a rectangular wedge hole or an oval wedge hole.
Picture	Type	Description
Standard End Connectors
	C65994 end connector	C65994 end connector Narrow guide horn pin diameter: 1-1/8" Only fits on T41 and WE210 track links Thinner bottom end, long and thin strengthening rib Seen on M3 Medium tanks and on "Michael", the 2nd production M4A1(75) in Bovington Photo courtesy of Richard Stickland
	C55596 end connector	C55596 end connector Narrow guide horn pin diameter: 1-1/8" Only fits on T41 and WE210 track links Thicker bottom end, shorter and thicker strengthening rib
	C55592 end connector (narrow)	C55592 end connector Narrow guide horn pin diameter: 1-1/4" Fits on every track link, except T41 and WE210
	C55592 end connector (wide)	C55592 end connector Wide guide horn pin diameter: 1-1/4" Fits on every track link, except T41 and WE210. The end connector with wide guide horns do no appear on WW II Shermans.
		Comparison shot showing the 7056829 end connector with wide horn (left side) and the C55592 end connector with narrow horn (right side). Photo courtesy of Kurt Laughlin
Extended End Connectors According to Mike Canaday, the official nomenclature in the Standard Nomenclature List for the M4A3 76mm (ORD 9 SNL G-205) from the 1950's lists the actual official US Army name of the part in question is 7055614 Connector, track link, outer (Duck-bill). This part is listed with the T48, T49, T51, T54E1, T56, T56E1, T62, and T74 tracks, and NOT with the T41, T47E1, or the "CUFF TYPE". According to Steve Zaloga, the reason there was no standardization of duck-bill parts numbers was that a large portion of the duckbill EECs used in Europe in fall 1944-winter 1945 were locally produced in Europe. The Army was so desparate for these due to the muddy weather that they put out local contracts in France and Belgium to have duckbills locally manufactured.This was the reason for all the variation in detail and design.
	First type	Type 1: pressed extension welded to second type standard end connector with rectangular wedge hole. The photos show EEC as fitted on a M4A3(75) W currently displayed in Bastogne (Belgium).
	Second type	Type 2: similar to type 1, with strengthening ribs, one-piece assembly. The photos show EEC as fitted on a M4A2(75) currently stored at the Saumur Tank Museum (France).
	Third type	Type 3: rectanglar wedge hole, no "dip", two-piece welded assembly. The photos show EEC as fitted on a M4(75) currently displayed in Wibrin (Belgium).
	Fourth type	Type 4: oval wedge hole with "dip", two-piece welded assembly. The three photos show EECs as fitted on a M4A1(75) currently displayed in Bayeux (France).
	Fifth type	Type 5: oval wedge hole, with dip and web, one piece. There are two variants, as shown here. On the first variant, the "dip" is straight, on the second variant it looks like a hook. The photos show EECs as fitted on a M4A4(75) currently displayed in Oosterbeek (Netherlands).
	Sixth type	Type 6: rectangular wedge hole, large strengthening ribs. Welded assembly. The photos show EECs as fitted on an M4A1 75mm on a fire range in Eastern France. Combat use of this type of EECs is confirmed by a photo showing a tank of the 6th Armored Division in Nancy area, in October, 1944.
	Platypus and Rat grousers	“Platypus grousers” were developed in the second half of 1944 by the Mechanical Warfare Experimental Establishment in Italy. These were applied to rubber tracks, and alternated with the Sherman’s standard issue grousers. The Platypus grousers combined the functions of both the standard grousers and the extended end connectors, providing extra traction as well as lowering ground pressure, thereby increasing the tank’s off road mobility particularly in muddy conditions. ("Rat grousers" were similar, but designed to fit on steel tracks.) In a report dated 9 Feb 1945, the Technical Staff went so far as to state that "Platypus grousers...entirely revolutionize the performance of Sherman in mud." In any case, in 1945, a few Commonwealth units in Italy were supplied with Platypus grousers in anticipation of the Spring Offensive. Note that there were 2 methods to fit these extended grousers on tracks. The first method was the standard one consisting of bolting the grouser on the track, using holes in the track pins. The second method, used for tracks that didn't have holes in the track pins, consisted in welding 2 wedges to the grouser (as seen on the grouser on top of the picture), and bolting the assembly to standard end connectors.

	EEC resistance on irregular ground	These photos show type 3 EECs that tend to get damaged due to the use on irregular ground. Some of the EECs are twisted and/or ripped, and some others are already broken.

End connectors for Vertical Volute Spring Suspension (VVSS) tracks

Introduction :

A Sherman track is made of shoes. A shoe is an assembly of one link, two connections (a.k.a. end connectors), two wedges and two nuts.
The track link pins were connected by means of end connectors which were held in place by a bevelled wedge nut. The nut is part number 503330 and the wedge is part number A176090. Because of this slight bevel the track links were forced to curl inward. The end connectors were made of cast steel with integral guide horns.
There were at least three standard end connector types. They come in two basic shapes, one with a narrow guide horn (for 1-1/8" and 1-1/4" diameter pins) and one with a wide guide horn (1-1/4" diameter pins).
The standard end connectors can be seen with a rectangular wedge hole or an oval wedge hole.

Picture

Type

Description

Standard End Connectors

C65994 end connector

C65994 end connector
Narrow guide horn
pin diameter: 1-1/8"

Only fits on T41 and WE210 track links

Thinner bottom end, long and thin strengthening rib
Seen on M3 Medium tanks and on "Michael", the 2nd production M4A1(75) in Bovington

Photo courtesy of Richard Stickland

C55596 end connector

C55596 end connector
Narrow guide horn
pin diameter: 1-1/8"

Only fits on T41 and WE210 track links

Thicker bottom end, shorter and thicker strengthening rib

C55592 end connector
(narrow)

C55592 end connector
Narrow guide horn
pin diameter: 1-1/4"

Fits on every track link, except T41 and WE210

C55592 end connector
(wide)

C55592 end connector
Wide guide horn
pin diameter: 1-1/4"

Fits on every track link, except T41 and WE210.
The end connector with wide guide horns do no appear on WW II Shermans.

Comparison shot showing the 7056829 end connector with wide horn (left side) and the C55592 end connector with narrow horn (right side). Photo courtesy of Kurt Laughlin

Extended End Connectors

According to Mike Canaday, the official nomenclature in the Standard Nomenclature List for the M4A3 76mm (ORD 9 SNL G-205) from the 1950's lists the actual official US Army name of the part in question is 7055614 Connector, track link, outer (Duck-bill). This part is listed with the T48, T49, T51, T54E1, T56, T56E1, T62, and T74 tracks, and NOT with the T41, T47E1, or the "CUFF TYPE".

According to Steve Zaloga, the reason there was no standardization of duck-bill parts numbers was that a large portion of the duckbill EECs used in Europe in fall 1944-winter 1945 were locally produced in Europe. The Army was so desparate for these due to the muddy weather that they put out local contracts in France and Belgium to have duckbills locally manufactured.This was the reason for all the variation in detail and design.

First type

Type 1: pressed extension welded to second type standard end connector with rectangular wedge hole.

The photos show EEC as fitted on a M4A3(75) W currently displayed in Bastogne (Belgium).

Second type

Type 2: similar to type 1, with strengthening ribs, one-piece assembly.

The photos show EEC as fitted on a M4A2(75) currently stored at the Saumur Tank Museum (France).

Third type

Type 3: rectanglar wedge hole, no "dip", two-piece welded assembly.

The photos show EEC as fitted on a M4(75) currently displayed in Wibrin (Belgium).

Fourth type

Type 4: oval wedge hole with "dip", two-piece welded assembly.

The three photos show EECs as fitted on a M4A1(75) currently displayed in Bayeux (France).

Fifth type

Type 5: oval wedge hole, with dip and web, one piece. There are two variants, as shown here.
On the first variant, the "dip" is straight, on the second variant it looks like a hook.

The photos show EECs as fitted on a M4A4(75) currently displayed in Oosterbeek (Netherlands).

Sixth type

Type 6: rectangular wedge hole, large strengthening ribs. Welded assembly.

The photos show EECs as fitted on an M4A1 75mm on a fire range in Eastern France.

Combat use of this type of EECs is confirmed by a photo showing a tank of the 6th Armored Division in Nancy area, in October, 1944.

Platypus and Rat grousers

“Platypus grousers” were developed in the second half of 1944 by the Mechanical Warfare Experimental Establishment in Italy. These were applied to rubber tracks, and alternated with the Sherman’s standard issue grousers. The Platypus grousers combined the functions of both the standard grousers and the extended end connectors, providing extra traction as well as lowering ground pressure, thereby increasing the tank’s off road mobility particularly in muddy conditions. ("Rat grousers" were similar, but designed to fit on steel tracks.) In a report dated 9 Feb 1945, the Technical Staff went so far as to state that "Platypus grousers...entirely revolutionize the performance of Sherman in mud." In any case, in 1945, a few Commonwealth units in Italy were supplied with Platypus grousers in anticipation of the Spring Offensive.

Note that there were 2 methods to fit these extended grousers on tracks.
The first method was the standard one consisting of bolting the grouser on the track, using holes in the track pins.
The second method, used for tracks that didn't have holes in the track pins, consisted in welding 2 wedges to the grouser (as seen on the grouser on top of the picture), and bolting the assembly to standard end connectors.

EEC resistance on irregular ground

These photos show type 3 EECs that tend to get damaged due to the use on irregular ground. Some of the EECs are twisted and/or ripped, and some others are already broken.