1943 International Harvester M5 Half-Track

This vehicle, Lot 58, sold for £135,000 ($177,778), including buyer’s premium, at the H&H Imperial War Museum Duxford Motor Car Auction on November 15, 2017.

The United States was fighting in World War II by 1942, and one of the new technologies that proved itself was the half-track.

The standardized M2 Half-Track Personnel Carrier and M3 Half-Track Car — built at White, Diamond T, and Autocar — were good combat vehicles, yet deficiencies surfaced.

U.S. Army Ordnance wanted enhancements in the design and engineering, so bringing in a fourth manufacturer would keep production humming along at White, Diamond T and Autocar.

In addition, our allies were also requesting more half-tracks, under Lend-Lease. The U.S. Army deemed that it made sense to add a fourth manufacturer.

Enter International Harvester

The U.S. government halted civilian truck production during March 1942, which put International Harvester in a bit of a lurch, as they had only smaller defense sub-contracts at that time. So IH went all in on getting a contact as the fourth half-track builder.

The changes made on IH-production half-tracks were enough to warrant new designators. The M3 type was named the M5 when made at International Harvester. The M2 was, in essence, the M9, although all M9 production was actually the M9A1 (the A1 indicating for all builders and half-track types the use of a ring mount at the front passenger’s position for a .50-caliber M2 machine gun).

There are two easy ways to distinguish an IHC half-track from the other three builders. The front fenders are of a simpler design and construction, and the crew compartment armor has curved corners.

The curved corners were for crew safety. Armor on the M2 and M3 made at the three original manufacturers was bolted together in the corners. While this made the half-track quicker and easier to build, the bolts tended to sheer off and become shrapnel inside the crew compartment when the armor plate caught a direct hit from heavier-caliber shells.

A bigger engine

The International Harvester M5 Half-Track also has a larger engine. Even before the use of the heavier curved armor, the Army wanted a more-powerful engine, as they were considering the use of all-steel tracks (due to wartime rubber shortages). The IH Half-Tracks were built with their heavy-duty-truck 143-hp Red Diamond 450 inline 6-cylinder engine instead of the 386-ci, 127-hp White 160AX engine that the three original builders installed.

After all the back and forth between International Harvester and the Army Ordnance board over the design changes and supply spares contracts, the first production M5 Half-Track was finally built in November 1942.

IH-produced half-tracks were almost exclusively for Lend-Lease distribution to our allies. This decision eased supply problems for the U.S. Army in the field. Only a handful of IH M5 Half-Tracks remained in the U.S. for training use.

While the Soviets were not particularly interested in the IH M5 Half-Track (they wanted trucks), the British and French used the vast majority of them. Our example is described as having been part of the Free Polish forces. After World War II, France and Israel were the biggest users.

The Big Dog among IH aficionados

Few IH M5 Half-Tracks are in the U.S., but it is possible to maintain them today with stock International truck powertrain components.

The Red Diamond 450 engine was used in larger semi trucks, such as the K-8 through K-11 (and the post-war KB-8 through KB-11 with minimal changes).

The examples that remain in Europe are easier to maintain and restore, as the original service parts were shipped over during the war with the whole half-tracks. Still, some half-track-specific components are made out of Unobtainium, so modern owners tend to be cozy with their local machine shop.

A decade ago, an IH-made M5 Half-Track commanded a slight premium over a standardized Autocar/Diamond T/White in the Historic Military Vehicle market. The IH model is now easily worth a premium over the others.

Being “Substitute Standard” for the U.S. Army meant that no M5s were officially brought back to the U.S. after World War II. Yet the M2 and M3 variants remained in U.S. service into the Korean War era — and even later with National Guard units.

A few U.S. companies specialized in converting surplus half-tracks into civilian trucks.

These days, U.S. collectors are very interested in the International Harvester M5 Half-Track. In fact, IH enthusiasts are really into them. If you show up with one at the annual International Harvester Collectors Club’s Red Power Roundup, you are the Big Dog on campus.

The same guys who like and own 1911–14 IHC Mogul through 1982–84 model 7488 tractors have taken a shine to the half-tracks, and they have the ability to handle and care for a 15,000-pound armored vehicle. And, they can pay for one.

The selling price is quite dear on our featured unit (even compared to the generous auction-house estimate), but I didn’t find myself flabbergasted.

While the restoration was done a few years back, it’s still an outstanding unit that gets exercised regularly and comes from a well-known European collection that specializes in historic military vehicles.

I’ll call this a case of getting what you pay for — while stepping up quite a bit to get it. ♦

(Introductory description courtesy of H&H.)