7.5 cm PaK 40 auf Sfl. Lorraine Schlepper ‘Marder I’ (Sd.Kfz.135)

German Reich (1942)
Self-Propelled Anti-Tank Gun – 170-184 Converted

Even before the Second World War, the famous German tank commander Heinz Guderian had predicted the need for highly mobile self-propelled anti-tank vehicles, later known as Panzerjäger or Jagdpanzer (tank destroyer or hunter). However, in the early years of the war, beside the 4.7 cm PaK (t) (Sfl) auf Pz.Kpfw. I ohne turm, which was in essence just a 4.7 cm PaK (t) gun mounted on a modified Panzer I Ausf.B tank hull, the Germans did little to develop such vehicles. During the invasion of the Soviet Union, the Wehrmacht encountered tanks which they had trouble dealing with effectively due to their thick armor (T-34 and KV series) and were forced to introduce a number of different hastily built and developed Panzerjäger based on any chassis that was available. From this, a series of vehicles generally known today as the ‘Marder’ (Marten) was created. The first such vehicle was built by using a captured French Lorraine 37L fully-tracked armored tractor and arming it with the German 7.5 PaK 40 anti-tank gun.

History

During Operation Barbarossa, the Panzer Divisions were once again spearheading the German advance, as in the previous year in the West. Initially, the lightly protected Soviet early tanks such as the BT series and the T-26 proved to be easy prey for the advancing German Panzers. However, the Panzer crews were shocked to discover that their guns were mostly ineffective against the armor of the newer T-34, the KV-1 and KV-2. German infantry units also discovered that their 3.7 cm PaK 36 anti-tank towed guns were of little use against these. The stronger 5 cm PaK 38 anti-tank towed gun was only effective at shorter distances and it had not been produced in great numbers by that time. Luckily for the Germans, the new Soviets tanks were plagued by a not-yet-matured design, inexperienced crews, a lack of spare parts and ammunition, and poor operational use. Nevertheless, they played a significant role in slowing down and eventually stopping the German assault in late 1941. In North Africa, the Germans also faced increasing numbers of Matilda tanks which also proved to be hard to knock out.

The experience gained during the first year of the invasion of the Soviet Union raised a red alert in the highest German military circles. One possible solution to this problem was the introduction of the new Rheinmetall 7.5 cm PaK 40 anti-tank gun. It was first issued in very limited numbers at the end of 1941 and the start of 1942. It became the standard German anti-tank gun used until the end of the war, with some 20,000 guns being built. It was an excellent anti-tank gun, but the main problem with it was its heavyweight, making it somewhat difficult to deploy and hard to manhandle.

The solution to this problem was to mount the PaK 40 on available tank chassis. These new Panzerjäger vehicles followed the same pattern: most were open-topped, with limited gun traverse, and thin armor. They were, though, armed with an effective anti-tank gun, and usually with one machine gun. They were also cheap and easy to build. Panzerjägers were, in essence, improvised and temporary solutions, but effective ones nevertheless. Just as the name suggests (Panzerjäger means “tank hunter” in English), they were designed to engage enemy tanks at long ranges on open fields. Their primary mission was to engage enemy tanks and to act as fire support at long range from carefully selected combat positions, usually on the flanks. This mentality led to a series of such vehicles named Marder that was developed using many different armored vehicles as a basis.

The first series of Marder vehicles was based on captured French armored vehicles. While small series were built using tank chassis, the majority were built using captured Lorraine 37L fully-tracked armored tractors. The Lorraine 37L would be also converted into a self-propelled artillery gun. The man responsible for the creation of the first Marders was Major Alfred Becker. His design was presented to Adolf Hitler in May 1942, who immediately ordered that 100 armed with 10.5 cm and 15 cm artillery guns and 60 PaK 40 armed vehicles should be built. Due to the high demand for self-propelled anti-tank vehicles, the majority of the available captured Lorraine 37Ls would be converted into Marder I (as this vehicle would be known) vehicles.

The Lorraine 37L

After the First World War, the French Army had shown interest in developing a tracked armored supply vehicle. The first vehicle that was adopted for this role was the small Renault UE. During 1935, the Lorraine company began working on a faster alternative for this vehicle meant for the cavalry units. By 1937, the first prototype of the Lorraine 37L was completed. Its performance was deemed sufficient by the French Army and ordered into mass production. It was mainly used for the transport of ammunition, fuel and other supplies. There was also an infantry transport variant called Voiture blindée de chasseurs portés 38L, which can be identified by an added box-shaped armored superstructure mounted to the rear.

From 11th January 1939 to 16th May 1940, over four hundred Lorraine 37L armored supply vehicles were built. By the time of France’s capitulation, the Germans had managed to capture some 300 Lorraine 37L vehicles. In German service, these vehicles were known as the Lorraine Schlepper(f).

Name

During its service life, this self-propelled anti-tank gun was known under several different names. On 1st August 1942, it was known as the 7.5 cm PaK 40 auf Sfl.LrS. Sfl, which stands for ‘Selbstfahrlafette’, which can be translated as ‘self-propelled’, while LrS stands for Lorraine-Schlepper. In May 1943, the name was changed to 7.5 cm PaK 40/1 auf Sfl.Lorraine-Schlepper. In August 1943, it was again changed to Pz.Jaeg. LrS fuer 7.5 cm PaK 40/1 (Sd.Kfz.135). It received the Marder I name, by which it is best known today, due to Adolf Hitler’s personal suggestion made at the end of November 1943.

Production

Following the decision to adopt the Marder I into service on 9th June 1942, the German Waffenamt (Ordnance Department) laid out the plans for a number of vehicles to be built by the Becker Baukommando workshop located in Paris and the H.K.P Bielitz workshop. The main supplier of the Marder I components was Alkett. This firm was responsible for modifying the PaK 40’s lower carriage and gun shield, but also for the assembly of the upper superstructure for the Marder I vehicle.

The monthly production target in Paris was 20 vehicles in June 1942 and 78 in July, with an additional 30 in June and 50 in July from Bielitz. In total, 178 were planned to be converted. The actual production numbers were a bit lower, with 170 rebuilt vehicles completed. 104 were converted in July and the remaining 66 in August 1942.

Unfortunately, the exact number of rebuilt vehicles depends on the source. While the number of 170 is quite commonly found in the literature, there are still some disagreements between the sources. The previously mentioned production numbers were according to T.L. Jentz and H.L. Doyle (Panzer Tracts No.7-2 Panzerjäger). Author Walter J. Spielberger, in his book Beute-Kraftfahrzeuge und Panzer der Deutschen Wehrmacht, mentions that 184 were planned but 170 were actually built. D. Nešić (Naoružanje Drugog Svetsko Rata-Nemačka) mentions 179 vehicles being built. Author A. Lüdeke (Waffentechnik im Zweiten Weltkrieg) lists a number of 184 vehicles being built.

The Design

Suspension

The Marder I suspension consisted of six road wheels placed on each side, suspended in pairs and placed on three bogies. Above each bogie, a leaf-spring unit was placed. There were also four return rollers, front-drive sprockets and an idler placed on each side at the rear. The transmission was placed in the front hull of the vehicle.

The Lorraine 37L suspension was a very robust and simple design. This was rather uncommon among pre-war French tank designs, which generally had overly complicated suspension systems. In its original role as an armored tractor, the Lorraine 37L had little problems following French tanks on good or muddy terrain. The German version had an increased weight of up to 8.5 tonnes (7.5 or 8 tonnes depending on the source), compared to the original 6 tonnes. While the Lorraine 37L suspension system was considered adequate in its original role, the added extra weight proved to be problematic, especially on the Eastern Front mostly due to low temperatures and muddy roads. In addition, vibrations caused by firing the main gun put enormous stress on the suspension, which increased the chance of malfunctions or damage.

The Engine

The Marder I engine type and its position were not changed from the original Lorraine 37L. The Delahaye Type 135 6-cylinder water-cooled 70 hp@2800 rpm engine was located in the center of the vehicle’s hull. While the maximum speed with this engine was a solid 35 km/h, the cross country speed was only 8 km/h. The operational range was also quite limited, with 120 km on good roads and 75 km cross country. The low speed on bad roads and the small operational radius is possibly the main reason why the Marder I was mostly allocated to Infantry Divisions. The exhaust pipe was located on the left side of the hull and was protected by a thin curved armored plate. The Marder I’s fuel capacity was 111 liters.

Superstructure

The Marder I was built using mostly unmodified Lorraine 37L chassis, by simply replacing the original rear positioned transport compartment with a new armored superstructure. The new armored superstructure had a relatively simple design, which consisted of rectangular armored plates welded together. These armored plates were angled in order to provide additional protection, as the armor thickness was quite low. The front of this armored superstructure was protected by the main gun’s enlarged gun shield. The Marder I was an open-top vehicle and, for this reason, a canvas cover was provided to protect the crew from bad weather. Of course, this offered no real protection during combat. The added superstructure served as the crew fighting compartment for operating the main gun. Due to the Marder I’s tiny size, the crew compartment offered a small working space.

Armor Thickness

The Lorraine 37L, being designed to fulfill the role of a supply vehicle, was only lightly armored. The front armor was 12 mm thick, while the top and bottom were only 6 mm thick.

The superstructure armor thickness, depending on the source, is usually noted to be around 10 to 11 mm all-around thick. Luckily, the Tank Encyclopedia team was given access to the Marder I auf Geschutzwagen Lorraine Schlepper(f) at the French Tank Museum in Saumur, France. A digital micrometer was used to measure the armor thickness of the upper superstructure. When books state that the armor thickness was 11 mm, this is the design thickness. In reality, the rolled armor plate used by the Germans was not of a precise thickness. It varied over the length of the plate within a certain tolerance range. It should be remembered that these measurements included the thickness of the primer base coat and final coat of paint.

The Armament

The main gun chosen for the Marder I was the standard 7.5 cm PaK 40/1 L/46. This gun, with its slightly modified mount, was placed above the engine compartment. Its original two-part armored shield was replaced with a single enlarged shield covering the front of the superstructure. The elevation of the main gun was -8° to +10° (or -5° to +22° depending on the source) and the traverse: -20° to +20° (-16° to +16° depending on the source). The total ammunition load also differs depending on the source. According to authors H. Doyle (German Military Vehicles) and G. Parada, W. Styrna and S. Jablonski (Marder III), the Marder I could carry 40 rounds. Authors T.L. Jentz and H.L. Doyle (Panzer Tracts No.7-2 Panzerjager) mentions a number of 48 rounds.

In order to relieve the stress on the elevation and traverse mechanisms during long drives, a travel lock was added. Secondary armament consisted of one 7.92 mm MG 34 machine gun and possibly the crew’s personal weapons.

Interestingly, there is a photograph of a Marder I armed with the 5 cm PaK 38. More information on the circumstances under which this modification occurred is unfortunately lacking. It could have been either a field modification, which is very likely or a simple training vehicle. It could be also a post-war modification, possibly done by the French. What is interesting is the front gun shield had an added armor plate around the gun.

Crew members

According to the T.L. Jentz and H.L. Doyle (Panzer Tracts No.7-2 Panzerjager), the Marder I had a crew of four which consisted of the commander, gunner, loader and the driver. Other sources, for example, G. Parada, W. Styrna and S. Jablonski (Marder III), give a number of five crew members. The reason why authors state different information regarding the number of crew members is not clear. To complicate matters further, there are old photographs of the Marder I with either three or four crew members in the rear fighting compartment (besides the driver, who was in his own compartment at the front).

The driver was positioned inside the Marder I hull and was the only crew member that had all-around armor protection. To reach his own position inside the vehicle, a horizontally positioned two-part rectangular-shaped hatch was used. For observation, there were two simple vision slots on the front and one on each side. While these had a simple design, the Germans never replaced them, probably to save time or simply because they had nothing better at hand.

The remaining crew members were placed in the armored superstructure compartment. The gunner would be positioned to the left of the gun. On the front of the gun shield, there was a small armored slide that could be opened for use of the gun sight. To the right of the gun was probably the position occupied by the commander and behind him was the loader. If there was a fifth crew member, he would likely have been a radio operator for the Fu 5 radio set or an assistant loader. If there were only four crew members, another crew member would have served as a radio operator.

Organization

The Marder I was used to equip smaller anti-tank companies (Panzerjäger Kompanie). These were allocated as reinforcement to the anti-tank battalions (Panzerjäger Abteilungen) mostly of Infantry and a few Panzer Divisions. The anti-tank companies were initially equipped with nine Marder I vehicles. From early 1943, the number of vehicles per company was usually increased by one more vehicle.

Use in combat

The Marder I would mostly see service in France, but also on the Eastern Front and in smaller numbers in North Africa.

In France

The majority of newly built Marder I vehicles would be used by units stationed in France. It was standard practice that the unit equipped with the Marder I would retain its vehicles until it was relocated to another front. When that happened, they would be supplied with another self-propelled anti-tank vehicle or with towed 7.5 cm PaK 40 guns. This was done mostly to ease maintenance and procurement of spare parts.

During late June 1942, the German High Command (Oberkommando des Heeres – OKH) predicted that at least 20 Marder Is would be ready for operational field test trials by the end of July 1942. Two Panzer Divisions, the 14th and 16th, were initially chosen for this purpose. In July, the OKH decided that the first Marder I were instead to be given to the 15th, 17th, 106th and 167th Infantry Divisions and to the 26th Panzer Division once they were available in sufficient numbers.

The 15th Infantry Division received its 9 Marder I vehicles by late July 1942. On 21st January 1943, the 15th Infantry Division received an additional twelve Marder III vehicles based on the Panzer 38(t). Its Marder Is were then given to 158th Reserve Division.

The 17th Infantry Division received 9 Marder I by the end of July 1942. Their use by this unit was problematic from the start due to a lack of radio operators and mechanics. Additional problems were created by the inexperience of the driver with such fully tracked vehicles. The height of some of these drivers was also problematic, as they had issues entering their positions inside the Marder I hull. What was interesting was the fact that the driver would go out of the vehicle during the firing of the main gun. The capacity of the inboard batteries was too weak. For example, they would usually be discharged after only one hour of using the radio with the engine off. This would result in the batteries having no power to start the engine. Then, it had to be manually started by two crew members by using a hand crank, which in practice proved to be difficult to do. One more big flaw was noted during a long off-road marches, with the accumulating mud and earth that could lead to the loss of the rear idler wheels. At least two vehicles were reported to have lost the rear idler.

The 106th Infantry Division operated an anti-tank company with 9 Marder I vehicles after late July 1942. One command vehicle based on the Panzer I and six ammunition transport vehicles based on the Panzer I were also available. In late February 1943, the 106th Infantry Division was repositioned to the Eastern Front and the Marder I vehicles of the anti-tank company were replaced with 9 towed 7.5 cm PaK 40 anti-tank guns.

The 167th Infantry Division had 9 Marder I vehicles up to late January 1943. When it was sent to the Eastern Front in late February 1943, all the Marder Is were replaced with 9 towed 7.5 cm PaK 40 anti-tank guns.

The 26th Panzer Division operated a company of Marder I vehicles for a short time from 1st January to 1st May 1943.

By the end of 1942, the 1st Panzer Division was repositioned to France for recuperation and refitting with new weapons and equipment. At this time, it was reinforced with one Marder I company. These vehicles would be replaced with Marder IIIs in late February 1943.

During 1943, many more units stationed in France would also be reinforced with Marder I vehicles before they were relocated to other fronts. The number of supplied Marder I vehicles varied between each division. For example, the 94th Infantry Division received 14, while the 348th Infantry Division received only 5. By the end of 1943, there were 94 Marder Is with 83 operational vehicles in Western Europe. In total, at the start of 1944, there were 131 Marder Is available. The last known unit that received a company of 10 vehicles was the 245th Infantry Division on 13th May 1944.

The Marder I would see extensive action during the Allied Normandy landings in June 1944. While they managed to achieve some success, nearly all were lost with the German defeat in France. The 719th Infantry Division was the last unit to still possess 7 (with 3 operational) Marder Is on 27th January 1945. Interestingly, at the end of the war, the Belgian resistance managed to capture one Marder I vehicle.

In the Soviet Union

As stated previously, OKH plans for the Marder I stated that it was to be used to equip units stationed in France in order to ease maintenance and procurement of spare parts. But, as the demand for such vehicles on the Eastern Front was great, the original plans had to be changed. Through direct orders from the OKH (dated from the 9th August 1942), six divisions from Heeresgruppe Mitte were to be equipped with Marder I anti-tank companies.

The 31st Infantry Division was reinforced with a Marder I anti-tank company on the 27th of August 1942. Due to harsh conditions and strong Soviet resistance, by the end of June 1943, this unit had only 4 Marder I left. By the end of October, the last three Marder I was given to Pz.Jg.Abt 743 (Panzerjäger Abteilung). At the start of 1944, none of these were still operational, with two requiring extensive repairs, while the third could not be repaired.

The 35th Infantry Division received its Marder Is by the start of September 1942. By the end of 1943, only two non-operational vehicles were available

The 36th Motorized Infantry Division was to be reinforced with a Marder I company that was initially attached to the 2nd Panzer Division. By the start of December 1942, all 9 vehicles were operational. The last Marder I vehicle was lost in July 1943.

The 72nd Infantry Division received 9 Marder I vehicles together with 6 Muni-Anhaenger (ammunition and supply wheel trailers) on 3rd September 1942. When the vehicles arrived, it was noted that there were issues with the breech block mechanism which had to be repaired. Additional problems with transmission breakdowns were also noted. What is interesting is that the Marder I company also had a Panzer 38(t) that probably acted as a command vehicle. By the end of June 1943, there were 7 Marder Is operational with the last vehicle being lost by the end of the year.

One Marder I company was to be allocated to the 206th Infantry Division, but this company was instead given to the 72nd Infantry Division. This caused a delay in the delivery of the first five Marder I vehicles up to the end of 1942, with the remaining arriving in January the following year. By the end of June, there were 8 vehicles with 5 operational. By the end of 1943, there were still 7 vehicles with only five operational.

The last unit on the Eastern Front that received the Marder I was the 256th Infantry Division. Initially, it had eight Marder I vehicles in its inventory, dated from 3rd November 1942. At the start of 1943, there were 9 Marder Is with eight operational. By the end of the year, the number of vehicles was reduced to 7 Marder Is, with only three operational. The 256th Infantry Division would be reinforced with three additional Marder Is vehicles in early 1944.

While the Marder I had sufficient firepower to destroy any enemy tank in 1942/43, the Soviet weather simply proved too much for the Lorraine 37L chassis. This can be seen in a combat report made by Pz.Jg.Abt 72 (belonging to the 72nd Infantry Division), which states: ‘as experience has shown, these (Marder I) don’t have any significant combat value because of their limited employability due to the weather’. In another report made by Pz.Jg.Abt 256, it is stated that: ‘with the exception of the Marder I, the other weapons and vehicles have been proven useful’. Due to bad weather, low numbers, problems with spare parts and others, not many Marder Is would be used on the Eastern Front and they would be replaced with Marder II and III vehicles which were built on more reliable chassis.

In North Africa

While the majority of the Marder Is would be used on the Western and Eastern fronts, few would also be found in North Africa. The 334th Infantry Division was to be resupplied with a Marder I company and, for this reason, the crewmen necessary to operate these vehicles were to be sent to the Sprember training center at the start of December 1942. After the completion of the crew training, which lasted two weeks, this company with 9 Marder I and 6 ammunition transport vehicles were to be transported from Naples to Tunisia by using the large Me 323 transport planes. By 1st March 1943, there were 8 vehicles operational with 4 under repair. Due to losses, this company was reinforced with Marder III vehicles based on the Panzer 38(t) chassis in early April 1943. Two Marder Is together with a group of Marder III participated in the defense of the Kairouan Line against Allied tanks. In the following engagement, seven enemy tanks were destroyed with the loss of one Marder I and five Marder III.

Surviving vehicles

While nearly two hundred vehicles were built, only one Marder I still exists and can be seen at the Musée des Blindés, Saumur (France).

Conclusion

The Marder I tank hunter was an attempt to solve the problem of the low mobility of towed anti-tank guns, but it failed in many other aspects. The most obvious was the fact that it was built on a captured chassis which led to logistical problems, as spare parts for it would be difficult to find. The low armor thickness meant that, while it could engage enemy tanks at range, any kind of return fire would likely mean the destruction of this vehicle. The Marder I’s armor provided the crew with only a basic level of protection against rifle rounds or shrapnel. Its speed and operational range were also not too impressive. The suspension and the running gear were not adequate for the weather condition present on the Eastern Front.

In conclusion, the Marder I vehicle was far from perfect, but gave the German a means to increase the mobility of the effective PaK 40 anti-tank gun, thus giving them a chance to fight back against enemy armored formations.

Marder I on the Eastern Front, winter 1942-43.

7.5cm Pak 40/1 auf Geschutzwagen Lorraine Schlepper(f) Sd.Kfz.135 – Normandy, 1944.

Marder I in France, September 1944. Notice the camouflage nets.
Inspiration for the illustrations: RPM, Ironsides model kits

Sources

Walter J. Spielberger (1989), Beute-Kraftfahrzeuge und Panzer der Deutschen Wehrmacht. Motorbuch.
D. Nešić, (2008), Naoružanje Drugog Svetsko Rata-Nemačka, Beograd
T.L. Jentz and H.L. Doyle (2005) Panzer Tracts No.7-2 Panzerjager
A. Lüdeke (2007) Waffentechnik im Zweiten Weltkrieg, Parragon books
G. Parada, W. Styrna and S. Jablonski (2002), Marder III, Kagero
P. Chamberlain and H. Doyle (1978) Encyclopedia of German Tanks of World War Two – Revised Edition, Arms and Armor press.
D. Doyle (2005). German military Vehicles, Krause Publications.
L. Ness (2002), World War II Tanks And Fighting Vehicles The Complete Guide, HarperCollins Publishers
P. Chamberlain and H. Doyle (1971) German Army S.P. Weapons 1939-45, M.A.P. Publication.
P. Thomas (2017) Image Of War Hitler’s Tank Destroyers, Pen and Sword.
W.J.K. Davies (1979), Panzerjager German Anti-Tank Battalions of World War Two. Almark Publishing Co.Ltd.

Panzerjager LrS 7.5 cm PaK 40/1 (Sd.KFz.135) specifications
Dimensions	4.95 x 2.1 x 2.05 m
Total weight, battle ready	8.5 tonnes
Crew	4 (Commander, Gunner, Loader and Driver)
Propulsion	Delahaye Type 135 70 hp @ 2800 rpm
Speed	35 km/h, 8 km/h (cross country)
Operational range	120 km, 75 km (cross country)
Primary Armament	7.5 cm PaK 40/1 L/46
Secondary Armament	7.92 mm MG 34
Elevation	-20° to +20°
Traverse	25° to the right and 32° to the left
Armor	Superstructure: 10-11 mm Hull: 6-12 mm