The American Automobile Industry in World War Two
An American Auto Industry Heritage Tribute
By David D Jackson

Overview      The U.S. Auto Industry at the Normandy Invasion, June 6, 1944    The U.S. Auto Industry and the B-29 Bomber   U.S. Auto Industry Army-Navy "E" Award Winners   The Complete listing of All Army-Navy "E" Award Winners   Sherman Tanks of the American Auto Industry   Tank Destroyers of the American Auto Industry    M26 Pershing Tanks of the American Auto Industry   Serial Numbers for WWII Tanks built by the American Auto Industry

    Automobile Manufacturers:  American Bantam Car Company   Checker   Chrysler   Crosley   Ford   General Motors   Graham-Paige   Hudson
   Nash-Kelvinator   Packard      Studebaker    Willys-Overland

General Motors Divisions
(Undergoing development) Aeroproducts   Brown-Lipe-Chapin   Buick   Cadillac   Chevrolet   Cleveland Diesel   Delco Appliance   Delco Products   Delco Radio   Delco-Remy   Detroit Diesel   Detroit Transmission   Electro-Motive   Fisher Body   Frigidaire   GM Proving Grounds   GM of Canada   GMC   GMI   Guide Lamp   Harrison Radiator   Hyatt Bearings   Inland   Moraine Products   New Departure   Oldsmobile   Packard Electric   Pontiac   Saginaw Malleable Iron   Saginaw Steering Gear   Southern California Division   Rochester Products   United Motors Service

Truck and Implement Manufacturers:   American LaFrance   Autocar  Diamond T   Caterpillar   Clark Equipment Company   Cleveland Tractor Company   Federal Motor Truck   International Harvester    Mack Truck
   Marmon-Herrington Company   Massey-Harris   Pacific Car and Foundry  Reo Motor Car Company   R.G. LeTourneau   Seagrave Fire Apparatus   Ward LaFrance Truck Corporation   White Motor Company

Automotive Tire
   B.F. Goodrich    Firestone Tire and Rubber Company
 Updates and Additions  


 Pontiac Motor Division in World War Two / WWII
Pontiac, MI
Rest in Peace!

This page updated 11-14-2017.

The Pontiac Motor Division emerged from the original Pontiac Buggy Company, founded in 1893 by Edward Murphy.  In 1907 it became the Oakland Motor Car Company, which was acquired by General Motors in 1909.  In 1926 Oakland introduced its Pontiac line of automobiles.  They became so popular that the Oakland was discontinued.  A new Pontiac Plant was built in 1927.  It was within this plant that the Division produced the war products described below.

The new Pontiac Plant in 1927.  The Fisher Body Plant is across the railroad tracks.  The overhead conveyor transported the finished bodies from the Fisher Body plant to Pontiac final assembly plant.  This was long before GM combined the managements of the body and final assembly plants into one.  Today's automobile plants have both functions under one roof.  Photo added 12-25-2016.

Pontiac's Plant #4 was the first auto manufacturer to win the Navy "E" award on January 20,1942.  Pontiac received this award for delivering 20mm Oerlikon anti-aircraft guns to the Navy ahead of schedule.  Pontiac Plant #4 did not convert its Navy "E" award when it became a combined Army-Navy "E" Award, as it could have done.  This Navy "E" award was not noted by the War Department's Army-Navy "E" award public relations release dated December 5, 1945.  There is no mention of Pontiac being one of the original war plants to receive the Navy "E" award, nor that is was one of those that did not convert. 

As of November 1943 Plant #4 had added four stars and would add a fifth for a total of six awards..

This clip from the November 1943 "Pontiac at War" booklet shows the Pontiac Oerlikon Plant receiving the Navy "E" award for the third time.  It is also noted on the "E" for Excellence page of "Pontiac at War" had received four stars for the Navy "E" flag.

Pontiac's Plant #11 won the Army-Navy "E" Award one time for the manufacture of the Mark XIII aerial torpedo.
Pontiac's Plant #14 won the Army-Navy "E" Award one time.

Pontiac Motor Division of GM World War Two / WWII Production Numbers / Statistics:  20mm Oerlikon anti-aircraft cannon, 40 mm Bofors anti-aircraft cannon, Mark XIII aerial torpedoes, 155mm artillery shells, tank axles for the M-5 Stuart and M24 Chaffee tanks built by Cadillac, parts for Detroit Diesel to include fly-wheel housings, connecting rods and cylinder liners, truck engine castings for GMC to include six cylinder blocks for all GMC 270 engines, some but not all engine heads for GMC 270 engine, oil pump housings, bearing caps. 

Pontiac's first war job was building 20mm Oerlikon anti-aircraft cannons for the US Navy.  This particular weapon, along with the stand and gun sight, were all built by Pontiac.  This weapon is serial number 223843.  Author's photo from the 2016 Virginian Museum of Military Vehicles Open House.

 Author's photo.

Author's photo.

Data plates on the Mark 10 20mm gun stand.  The serial number on the middle plate is 267182. This matches the serial number on the bottom plate.  Author's photo.

The serial number on the Mark 4 gun breach is 223843.  Author's photo.

The brass Mark 4 gun sight assembly was also manufactured by Pontiac.  Author's photo.

It has a weight of 12 pounds.  Author's photo.

This twin 20mm Oerlikon anti-aircraft gun is on the destroyer escort USS Slater in Albany, NY.   The weapon closest to the camera was built by Pontiac.  Author's photo added 11-14-2017.

The serial number is 4919x.  Author's photo added 11-14-2017.

Pontiac began work on the 40mm Bofors anti-aircraft gun in January 1942.  Pontiac cleared 217,000 square feet of the sheet metal plant space to manufacture the weapon.  The Bofos could fire 130 rounds per minute, and the two pound projectiles had a range of 5,420 yards.  The 40mm Bofors was also produced by Chrysler and Firestone.  Author's photo.

On March 12, 1942 Pontiac began work on the Mark 13 aircraft torpedo.  The thirteen foot long weapon contained 5,222 parts and 1,225 assemblies.  The gyro, which guided the weapon to its target, turned at 9,000 rpms.  It had a diameter of 22.5 inches and weighed 2,216 pounds, of which 600 pounds was the Torpex explosive. The internal steam turbine propelled the Mark 13 at 33 knots for a maximum range of 6,300 yards.  The Naval Torpedo Section, Ameritorp Corporation, and International Harvester also produced the Mark 13 during WWII.  The four companies built 17,000 torpedoes.   1,500 were used in combat.  Author's photo from the Liberty Aviation Museum in Port Clinton, OH.

This Mark XIII is on display at the National Aviation Museum of the US Air Force.  Author's photo.

Author's photo.

This is the warhead section of the torpedo that would have the detonator and 600 pounds of Torpex explosive, 1.5 times more powerful than TNT.  Author's photo from the USS Silversides Museum in Muskegon, MI. 

This area would contain the alcohol fuel and compressed air to power the steam turbine.  Author's photo.

Author's photo.

 The steam turbine is at the rear of the Mark XIII.  Author's photo.

Author's photo.

The primary aircraft to carry the Pontiac Mark 13 torpedo was the TBM Avenger.  It was built by the Eastern Aircraft Division of GM in Trenton, NJ.  Author's photo taken at the Liberty Aviation Museum.

The Mark 13 was also carried by US PT boats.  One of 21,147 DUKW amphibious trucks built by GMC and Chevrolet during WWII is next to the PT boat. Pontiac supplied the engine blocks for the GMC 270 cubic inch engine used in the DUKW.  Author's photo taken at the Liberty Aviation Museum.

Pontiac built the front differential and axle for the Cadillac built M5 light tank.  Cadillac built 1,824 M5 and 3,530 M5A1 Stewart tanks in Detroit.  It also built 1,778 M8 which had a 75mm howitzer rather than the 37mm cannon.  Author's photo.

 After Cadillac ceased production of the M3, it produced the M24 Chaffee light tank.  Pontiac supplied the front drive axles for it.   Author's photo taken at the Ropkey Armor Museum.

Pontiac cast all of the engine blocks for 528,829 GMC 6x8 and 24,910 6x4 trucks.  This was the 270 cubic inch, six-cylinder engine.  Pontiac also disassembled and crated GMC trucks for overseas shipment.  This saved valuable shipping space on transport ships.  Author's photo.

Pontiac supplied the Detroit Diesel Engine Division of GM with fly-wheel housings, connecting rods, and cylinder liners for its diesel engines.   Author's photo.

The Detroit Diesel engine was used in 19,353 LCVPs or Higgins boats.  Detroit Diesels were also used in many other types of landing craft for the US Navy.  Author's photo from the 1st Division Museum in Wheaton, IL.

Two Detroit Diesel 6046 engines powered 10,968 M4A2 Sherman tanks.  Author's photo.

Pontiac at War
A Special Report to Employees of Pontiac Motor Division
November 1943
This booklet has a wealth of information about Pontiac's contribution to the war effort, starting in March 1941 up through its publication in 1943.  The three main war products; the 20mm Oerlikon, the 20mm Bofors, and the Mark XIII aerial torpedo all have several pages dedicated to them.  It includes an excellent history of Pontiac up until the start of WWII.  This rare booklet is a primary source document that allows a look back at Pontiac from its inception through 1943.

There is no date on the booklet.  However, presumed original owner wrote the date on the cover when he or she received it.  The date November 3, 1943 is documented on the page discussing the suggestion program.  The booklet must have been published, then, by the end of that month.

The history of Pontiac Motor Division from 1893 until WWII, as written by Pontiac, is included in the next three pages. 

In the next two pages Pontiac gives more information on its manufacture of the 20mm Oerlikon anti-aircraft cannon for the US Navy.

In the next three pages Pontiac gives details on its manufacture of the 40mm Bofors anti-aircraft cannon for the US Army.

Below are five pages on Pontiac's manufacture of Mark XIII aerial torpedoes and their use by the US Navy.

Below is information on Pontiac's manufacture of tank axles for the M5 Stuart light tank.

 Pontiac's manufacture of diesel engine parts described below was an important contribution to the war effort.  These engines were used in a variety of landing craft and tanks.

Pontiac's casting of engine blocks for GMC trucks and DUKWs is described below.

Pontiac and GMC were both located in Pontiac, MI.  Pontiac was able to assist in the war effort by crating for overseas shipment the 2-1/2 ton 6x6 GMC trucks.  This allowed GMC to focus on the important assembly of trucks for the war effort.

The above page gives more details on the continued awarding of Navy "E" award, and the four stars added by November 1943.  These would be for manufacture of the 20mm Oelikon anti-aircraft cannon.  This would imply that the awards for the Torpedo Plant and Plant 14 came later.  These would have been the combined Army-Navy "E" awards.





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