Ross Gear and Tool Company in World War Two
"The Gear"
Lafayette, IN
1906-1964
 1964-2015 as a Division of TRW
 2015-Current as a Division of ZF

This page updated on 9-18-2023.

Every half-track built during World War Two had a steering gear in it manufactured by Ross Gear and Tool Company of Lafayette, IN.  While most persons may want to know what type of engine or transmission is in a vehicle, they never ask what type of steering gear is in it.  Yet, if one cannot steer and control the direction of the vehicle, the engine and transmission are not of much use.  One has to be able to control the direction of the vehicle in an easy and reliable manner.  So, while the steering gear is hidden from normal view down in the engine bay, it performs a very important yet overlooked function.  Without well-engineered steering, the vehicle is going to be hard to steer and could therefore cause accidents.

All 53,625 half-tracks built by Autocar, Diamond T, International Harvester, and White were equipped with Ross TA26 steering gears.  This particular half-track, an M16A2, was built by the White Motor Company in Cleveland, OH.  It and its Ross steering gear served the militaries of two different countries in three different wars.  It served the United States Army in Europe during World War Two and in Korea and the French in Vietnam.  It ended its military service with the French Foreign Legion in the Horn of Africa.  It was on temporary display at the National Museum of the United States Air Force in Dayton, OH during the first half of 2021.

Ross Gear and Tool Company steering gears were in over 70 types of military vehicles during World War Two.  This small company near the banks of the Wabash River north of downtown Lafayette, IN produced an important but little recognized product that helped to win World War Two.  Below is its story.


"The Gear."
This is the current ZF factory in Lafayette, IN that was originally the Ross Gear and Tool Company.  The plant is at the corner of Heath Street and North 9th Street in Lafayette and is known to its employees as "The Gear."  The view is looking west.  The Ross Gear and Tool Company was originally located in a small building at Main and 9th Streets in downtown Lafayette starting in 1906, until this plant was built in 1912 several blocks north of the original facility.  Author's photo.

The portion of the building with the saw-tooth roof construction is the original factory.  This and any additions built prior to or during World War Two comprised the plant that built the company's World War Two products.  Author's photo.

The insignia for ZF is on a newer office building for the facility.  The Wabash River is several hundred yards to the west of the plant.  Purdue University is a mile to the west in West Lafayette.  David Edward "Dave" Ross was one of three Ross family members who started Ross Gear in 1906.  Dave Ross was a Purdue Engineering School graduate, and it was his many steering gear patents that made the Ross Gear and Tool Company a leader in steering gears in the United States.  Author's photo.

The plant has grown and expanded from its original building and is a leader in making electric steering systems.  Author's photo.

This 1933 plant photo shows the distinctive saw-tooth roof of the original factory.  It also shows the type of automobiles being produced at the time and the Wabash River in the background.  From the "The Ross Gear/TRW Commercial Steering Systems Centennial History-1906-2006."

This 1980 aerial photo shows the plant very much like it is today.  From the "The Ross Gear/TRW Commercial Steering Systems Centennial History-1906-2006."

During the first World War, the young company produced 1,000 steering gears for the Class B Standard Motor Truck. This was more commonly known as the Liberty Truck.  Document courtesy of Warren Richardson.

This World War One Class B Liberty Truck has been restored to operating condition by the First Division Museum in Wheaton, IL.  Author's photo.

Brothers David Linn Ross and William Ross founded Ross Gear and Tool on October 16, 1906.  William Ross was the President, David Linn was Secretary-Treasurer, and their cousin David Edward "Dave" Ross was the general manager of the company.  Dave Ross, who graduated from Purdue University in 1893, had been farming since his graduation.  However, he had also been very interested in new automobiles that were being built.  When the new Ross Gear was formed in 1906, he had already been awarded his first patent for a steering gear.  He sold this and three other designs that he had submitted to the U.S. Patent Office to the new company for $3,200.  These designs became the technology that helped establish the Ross Gear and Tool Company as a leader in steering gears.  Dave Ross would continue to invent and be the technical driving force behind Ross Gear until his death in 1943.  He had 84 patents assigned to him between 1906 and 1941.  Only four of the patents were with co-inventors.  His patents not only included steering gears, but an internal combustion engine, highway traffic safety devices, warm air furnace, and building construction, to name a few.  In his later years, he diversified his interests.  His patents reflect this with predominantly non-gear patents.  His first patent, awarded on February 18,1906, was Patent Number 879414 for "Steering Gear for Vehicles." His last patent, Number 2247410 and dated July 1, 1941, was for a "Hydraulic Coupling Device."

For most of his career at the company, David E. Ross was the General Manager.  He was made a vice-president along with his general manager title in 1920.  In 1932 he became president with the passing of Edward A. Ross.  He became chairman of the Ross Board of Directors in 1938 when David Linn Ross passed away.  But he was the "hands-on" type of person and liked to invent and then manage the development of his ideas in the plant.  He knew every employee by name and at the same time was either known as "Dave" or "Mr. Ross" by his employees.  In his spare time, he focused on his position with the Board of Trustees for Purdue University. 

The first steering gear the small company produced was the Model BA, based on a Dave Ross patent.  The next model, introduced in 1908 as the Model BL, was based on another Dave Ross patent issued that year.  The 1911 Model BF followed the same pattern as the first two Ross Gear models.  In 1923 the company introduced the Dave Ross cam and lever steering gear.  This was the same type of gear used by many medium and heavy duty trucks during World War Two.  Dave Ross, an 1893 graduate of Purdue University, was nominated by the Purdue Alumni in 1921 to be elected to the Purdue Board of Trustees.  Eventually he would become the President of the Board.  Upon his death in June 1943, most of his estate was given to the Purdue Research Foundation.  He is buried on a small hill overlooking Stadium Avenue and Purdue University.  To the east of the gravesite is the Ross-Aide football stadium, named in part after David E. Ross.

The David E. Ross Gravesite at Purdue University:  On November 6, 2021, I was at Purdue University to watch a football game in Ross-Aide Stadium, which is named in part after David Ross.  I have on previous occasions been to football games at the stadium but had no idea who the name Ross referred to in the stadium's name.  It was only while researching this page that I learned that it was named in part after David Ross.  After leaving the game, I found the David E. Ross memorial and gravesite, which is located on the highest point on the Purdue campus and overlooks the main university campus to the south.

A memorial marker is located along a paved sidewalk among a grove of trees on the hilltop.  Author's photo added 11-9-2021.

Author's photo added 11-9-2021.

David Ross' gravesite is a little ways off to the southwest of the marker.  One has to be looking for this, as its location is not obvious to the casual passerby.  Author's photo added 11-9-2021.

The grave marker is very simple yet encompasses who David Ross was and his contribution to Purdue University.  Author's photo added 11-9-2021.

I did not attend Purdue University.  I graduated from another Big Ten university and then moved to Indiana.  However, after moving to Indiana, I visited Purdue University for several years for social reasons.  Both of my children graduated from Purdue University.  My wife and I made many weekend trips to visit them in the combined seven years they attended school there.  So, for me, I have some strong attachments to this university, and it has an important place in my life.  Purdue University has become my adopted university.  David Ross' foresight and influence when he joined the Board of Trustees 100 years ago helped shape the Purdue University of today.

A David E. Ross Anecdote:  Even though Dave Ross had been inventing steering gears for automotive use since 1906, it was not until 1912 that he owned a car.  His first automobile was a used Wescott built in Richmond, IN. 

Dave Ross' first automobile may have been a 1908 Wescott.  Actually, there is more to this photo than just the type of vehicle Dave Ross started driving in 1912 at age 41.  More importantly, this shows the automotive technology for which the infant Ross Gear and Tool Company was designing and building steering gears at the time.  The automobiles were open and had wooden bodies and wheels.  This vehicle had a 15 hp, two cylinder engine and had a top speed of 35 mph.  I would assume that Dave Ross would have purchased a vehicle that had one of his steering gears in it.  It is always good to buy what you make.  If so, it would have been a Ross model BA or BL.

At the 1929 New York Auto Show, 17 of the 26 cars on display had Ross steering gears in them.  Also, in 1928, the company introduced roller bearings in the cam followers in its cam and lever steering gears.  This resulted in a 50% efficiency improvement in the units.  During the depression, the company remained the largest independent manufacturer of passenger car steering gears.  It also began to diversify into trucks, tractors, and off-highway equipment.  In 1934 the twin lever steering gear was introduced after being invented by Percy Newman.  This innovation increased the angular travel through which the gear could turn.  During World War Two, twin lever steering gears were the dominant type that Ross built for the war effort.

In 1956 Ross purchased Gemmer Manufacturing Company, its main independent domestic competitor.  Two years earlier, Chrysler started building its own power steering gears, which was Gemmer's biggest customer.  In 1964 Ross merged with the larger TRW.  This was done as Ross did not have access to the financial resources needed to compete in the automotive car and truck market.  In 2015 TRW was purchased by the German company ZF.  What is interesting is that Ross licensed its cam and lever technology to ZF in 1932.  What is unknown is whether Ross cam and lever technology was used not only in American vehicles, but also German ones during World War Two.

 Ross Gear and Tool Company in World War Two:

The Ross Gear and Tool Company of Lafayette, IN won the Army-Navy "E" flag five times during World War Two.
It won the first award in November 1942.

World War Two Products:  "The Ross Gear/TRW Commercial Steering Systems Centennial History-1906-2006" has provided a significant amount of information for this webpage.  It notes that Ross Gear supplied steering gears for over 70 different types of vehicles during World War Two. It produced millions of track pins for tanks and other armored vehicles .  It also produced universal joint yokes for Studebaker and made high-strength steel parts for half-track tracks.

Table 2 shows that Ross built at least 836,016 OEM gears for the war effort.

Information from the World War Two Industrial Facilities Report of 1943 indicates Ross had the capability to produce 240,000 tank track pins per quarter as of July 1943.  Track pin production started in June 1942.  The report also shows that Ross was tooled to produce 80,000 steering gears and parts per quarter.

Note:  Both Studebaker US6 2-1/2 ton 6x6 and 6x4 trucks and all half-tracks had two different types of Ross Gear and Tool Company parts in them.  Both vehicles used Ross steering gears, and the Studebaker trucks had Ross universal joint yokes.  Half-tracks had Ross steel parts in their tracks.  

At the start of World War Two, there were two other main suppliers of steering gears in the United States besides Ross Gear and Tool Company.  One was the Saginaw Steering Gear Division of General Motors, which supplied all of the steering gears for Chevrolet and GMC during the war.  The other was Gemmer Manufacturing Company of Detroit, MI which was the supplier for the Dodge series of 1/2 ton, 3/4 ton, and 1-1/2 ton trucks and other vehicles.  Gemmer also supplied some of the commercial trucking industry.

While not a gear supplier to other companies, the Ford Motor Company made its own steering gears.  However, Ross did supply parts for the steering gears for the Ford-built version of the Jeep.

This left Ross to supply steering gears to the remainder of the commercial trucking industry during the war.  As noted above, it supplied steering gears for 70 different vehicles.  Information is shown below on the type of gears and the vehicles in which they were used.

Ross Gear and Tool Company provided steering gears for the smallest of the American World War Two vehicles, the famous Jeep.  While most of the Jeeps were produced by the Ford Motor Company and Willys-Overland, this particular vehicle was one of 2,642 that was produced by the American Bantam Car Company, which invented the vehicle.  Ross Gear engineers worked with American Bantam engineers during the development process to obtain the proper steering gear for this new, ground-breaking vehicle.  This may have been the first World War Two project for the company.  Ross Gear would supply all of the T12 steering gears for the Jeeps that American Bantam and Willys-Overland made during World War Two.  Ross supplied the steering gear cams to Ford, which chose to make its own version of the Ross-designed steering gear.

 The American Bantam Jeep shown above is on display at the Atterbury-Bakalar Air Museum at the Columbus, IN airport.  This vehicle is serial number 1398 out of 2642 and was delivered to the Quartermaster Corps in April 1941.  Author's photo.

The Willys-Overland MB Jeep used Ross T12 steering gears.  Author's photo.

Ross also made the steering gears for the largest American wheeled vehicle of World War Two, the M26 and M26A1 tank transporter.  This was part of the tractor and trailer combination M25 tank transporter, commonly known in the vernacular as the Dragon Wagon.  This tractor was so large and hard to steer that it had one of the first Ross power steering systems on it, which was the Ross P780 power steering gear.  This tractor is the M26A1 version.  Author's photo.

Ross Steering Gear Types:  Ross provided five different types of steering gears for military vehicles during World War Two.  Only three are known to have been used.

Type I Single Lever Fixed Stud:  There are no known World War Two uses for the Type I.

Type II Single Lever Roller Stud:  There are no known World War Two uses for the Type II.

Type III Twin Lever Fixed Stud:  Jeeps and medium duty trucks used the Type III during World War Two.

Type IV Twin Lever Roller Stud:  Medium-heavy and heavy-duty trucks were the big user of the Type IV during World War Two.

Type V Hydraulically Powered:  The M26 tank transporter was the only production vehicle to use the Type V during World War Two.

Tables 1 and 2 below provide information on Ross Steering Gear part and assembly numbers and the vehicles in which they were used.  Table 1 lists known Assembly and Part Numbers and their Ross Type.  The known vehicle applications are then listed for the Assembly or Part Numbers.

Table 2 lists the vehicles by tonnage and application.  It also includes the number of vehicles of each type built during World War Two based on Army Ordnance Acceptances of Vehicles.  The astute observer will note that there are many trucks missing that may be similar to the ones built by the same manufacturer that would probably have been built with the same or similar Ross gear as those listed.  However, information is not available to confirm that a Ross gear was actually used.  Therefore, they have not been included.  Most of the information in Table 2 came from Army Ordnance technical manuals or supply manuals.  These manuals are not available for every vehicle built.  The ones that are available are mostly for the type trucks that are still in existence today and owned and maintained by military vehicle collectors.  Other information was found in the historical literature on the various vehicles and from actual military vehicle owners.

The assembly numbers give specific dimensional information on the basic model number.  Once a model was designed, assembly numbers were assigned by adding a "one" to the model number.  Then the last three digits were assigned in numerical order for each customer application to provide the proper fit and steering ratio.  As the model numbers increase, so does the weight of the vehicle.  An "A" behind a "T" indicates a modification to the original model.

In many cases, as shown below, only the Ross model number is known.  Assembly numbers were stamped on the steering gear for positive identification and proper ordering of spare parts.

Images of Vehicles with Ross Steering Gears:

1/2-Ton Trucks:

Ross Gear supplied the steering gears to nearby International Harvester, 121 miles to the east of Lafayette in Fort Wayne, IN.  The International M-1-4 1-ton 4x4 was used by both the USMC and the U.S. Navy.  This is one of 892 ambulances that the USMC and Navy purchased during World War Two.  Author's photo added 8-11-2021.

Another 231 M-1-4 1-ton 4x4s were produced as cargo trucks.  Author's photo added 8-11-2021.

1-Ton Trucks:

International Harvester built 9,094 M-2-4 1-ton 4x4 trucks with Ross steering gears.  All the trucks were the cargo version and went to the USMC.  Author's photo added 8-11-2021.

 1-1/2-Ton Trucks:

 International produced 6,532 M-3-4 1-1/2-ton that were used in a variety of applications by the U.S. Navy and USMC.  All had Ross steering gears.  Author's photo added 8-11-2021.

2-1/2-Ton Trucks: 

This is one of 218,863 2-1/2 ton 6x6 and 6x4 trucks built by Studebaker in South Bend, IN that had Ross steering gears in them.  Author's photo added 9-18-2023.

This truck was built by Reo in Lansing, MI under license from Studebaker.  The dump body was added after World War Two.  The 22,204 Reo-built trucks had Ross steering gears.  Author's photo.

Ross supplied 38,528 T66 steering gears for the International Harvester M-5-6 2-1/2 ton 6x6 truck.  Author's photo added 9-18-2023.

Paul Rea owns this Federal 2G dump truck.  It runs and is on the list to be restored.  It has a Ross TA21 steering gear.  Photo courtesy of Jeff Lakaszcyck.

4-Ton Trucks: 

The Diamond T 696-A 4-ton 6x6 wreckers came with Ross T71 steering gears.  Author's photo.

4-5-Ton Trucks:

This is one of 11,104 Autocar U-7144T 4-5-ton 4x4 tractors built during World War Two with Ross T72152 Cam and Lever steering gears.  Federal and White built similar models with the Ross T72152 for a total of 21,974 vehicles of this type. 

5-Ton Trucks:

10,798 M425/M426 COE 5 ton 4x2 tractors were built by International, Marmon-Herrington, and Kenworth with Ross T71 Cam and Lever steering gears.  Author's photo.  This image added 4-30-2021.

5-6-Ton Trucks:

 The 5-6-ton Autocar U-8144T was also produced by FWD and Mack.  This had a longer wheel base than the U-7144T series and used the Ross T75104 steering gear.  There were 6,719 of all three types built.  Author's photo added 9-18-2023.

6-Ton Trucks:

This is one of 3,211 Corbitt 50SD6 6 ton 6x6 prime movers that used Ross steering gears.  Photo courtesy of Jeff Lakaszcyck.

There were also 3,946 White Motor Company 666 prime movers built based on the Corbitt 50SD6 truck which used Ross model T75143 steering gear.  Author's photo added 8-11-2021.

This White 666 was built in 1945.  White also built another 3,047 666 series trucks with different cargo bodies.  Author's photo added 8-11-2021.

The next three photos show the Ross Model T75143 as part of the entire steering system.  The name "Ross" can be seen on the steering gear casting in the first two photos.  Author's photo added 8-11-2021.

Author's photo added 8-11-2021.

Author's photo added 8-11-2021.

7-1/2-Ton Trucks:

This Oshkosh W-709-C-T-5 is part of the collection of vehicles at the National Museum of Military Vehicles in Dubois, WY.  Author's photo added 9-18-2023.

The truck has a Ross Gear and Tool Company steering wheel that indicates the vehicle has the company's cam and lever steering system.  Author's photo added 9-18-2023. 

Author's photo added 9-18-2023.

This Oshkosh W-709 snowplow was purchased by the U.S. Corps of Engineers in 1943 and utilized a Ross steering gear.  Image courtesy of Tim Wright.

Ward-LaFrance built a total of 4,925 M1 and M1A1 wreckers with the Ross T74 cam and lever steering gear.  This is the M1 version.  Author's photo. 

This is the M1A1 version of the Ward LaFrance 10-ton wrecker with the Ross T74 cam and lever steering gear.  Author's photo. 

12-Ton Trucks:

5,871 Diamond T 980/981s were built with Ross T-75141 steering gear assemblies.  Author's photo. 


This Corbitt Company T20E4 12-ton 8x8 cargo truck has a Ross P780 steering gear and hydraulic ram booster.

The Cook Brothers' T20 8-ton 8x8 cargo truck was equipped with a Ross P780 steering gear and hydraulic ram booster.

20-Ton Trucks:

 Reo built 700 28-XS 20-ton 6x4 tractors powered by Cummins HB600 diesel engines with Ross T75161 steering gear assemblies. 

 Federal built 1,443 20-ton trucks the Ross T75161 steering gear assemblies. 

Truck Tractors:

The Pacific Car and Foundry-built M26 had a power assisted Ross P780 steering gear.  Author's photo added 9-18-2023. 

The Pacific Car and Foundry-built M26A1 also had a power assisted Ross P780 steering gear.  Author's photo. 

Unknown Tonnage:

 

Fifty Sterling DD115 4x4s were purchased by the U.S. Navy and had Ross T71 steering gears.  Image courtesy of Warren Richardson added 11-13-2020.

Scout Cars:   

The White M3A1 scout car utilized a Ross T26 steering gear.  This M3A1 was photographed at the Portland, IN MVPA show in September 2021.  Author's photo added 9-19-2021.

The owner of the vehicle opened up the engine bay for me so I could photograph the Ross T26 steering gear.  Author's photo added 9-19-2021.

The Ross name can be seen in the upper center of the T26 steering gear.  It is upside down in the photo.  Author's photo added 9-19-2021.

Half-Tracks:  All of the half-tracks shown below utilized the Ross TA26 steering gear.

This Autocar-built M15 was built with a Ross steering gear assembly.  Author's photo.

This Autocar M3 75mm gun carriage is equipped with Ross steering gears built in Lafayette, IN.   Author's photo.

Diamond T M3 half-tracks built during the Second World War had Ross steering gears installed in them.  Author's photo.

This excellent restoration of an International Harvester M5 halftrack has a Ross TA27004 gear assembly in it.  Author's photo.

This 1942 White M4A1 81mm mortar carrier used a Ross steering gear.  Author's photo.

This M3A1 half-track is on display at the Indiana Military Museum in Vincennes, IN.  Author's photo added 8-11-2021.

This is the Ross TA26 steering gear in the vehicle.  The steering gear is only 146 miles from where it was built in Lafayette, IN.  Author's photo added 8-11-2021.

Other World War Two Products: 

Ross manufactured track pins for armored vehicles during World War Two.  While it is unknown which tracked vehicles used Ross track pins, the M3 and M5 Stuart light tanks used a large number in each tank tread.  The pins were used to join individual shoes together to make an entire track.  On the M5A1 shown here, each small hole on the tread contains a pin.  There was a considerable amount used on each tank.   Author's photo.

The M4 high speed tractor used the chassis from the M3 light tank and was another big user of track pins.   Author's photo.

The best known of the American-built tanks was the M4 Sherman.  Being a medium tank and larger than the light Stuart tank, it had a longer track that used even more track pins than the Stuart.  There were 158 track pins used in each Sherman tank tread.  This is an M4A3(76) HVSS version of the Sherman.   Author's photo.

Post-World War Two Vehicles with Ross Steering gears:

Ross Gear supplied the TA67171 steering gear assembly for the over 240,000 M35 series 2-1/2-ton 6x6 trucks, like this version built by White Motors in the former Reo plant in Lansing, MI. 

Ross supplied 147,000 HP71137 power-assisted steering gear assemblies for the M54 5-ton 6x6 series truck like this Mack-built M54A2.  Author's photo.