The Murty Brothers Design A Better Tilt Cab: Used By Diamond T, International, Reo and Hendrickson. Built In Steel and Fiberglass

The CEO (Cab Over Engine) truck had been around since the earliest days of the 20th century. Its short length was a huge boon in many applications. But it had a major shortcoming: no easy access to the engine. Then in 1949, White introduced the revolutionary 3000, which had a lower, forward-mounted tilting cab that gave full access to the engine. It set the format for all compact tilt cab trucks to come.

But there was room for improvement, especially in the tilting mechanism. It took the Murty Brothers of Portland, Oregon to come up with an ingenious new system that made tilting much easier. The prototype they built for Diamond T was better than the White 3000 in just about every way, and it went on to be used by at least four major truck manufacturers and was built in steel and fiberglass. It’s time to give the unsung heroes of the tilt cab trucks their due props.

In 1949 the White Motor Company of Cleveland Ohio introduced a revolutionary new medium duty truck known as the 3000 series. The 3000 represented a new concept in truck design, the low forward mount tilt cab. Unlike contemporary ‘cab-over’ trucks which were little more than short nosed conventional trucks with raised cabs to clear the rear of the engine, the 3000 cab essentially sat mostly ahead of the engine which was under the seat riser. This design gave an unobstructed floor in front of a full-width bench seat and utilized a front axle set well back from the front of the truck. The engine was also set low in the frame which provided plenty of room for White’s large but low profile flat-head 6’s. The forward position of the driver’s seat and the set-back front axle gave unprecedented visibility and maneuverability, while the novel tilting cab provided excellent engine accessibility. The 3000 was a great success for White and stayed in production through 1967.

The Diamond-T Company of Chicago Illinois was a highly regarded truck manufacturer known for building very high-quality innovative trucks. In addition, Diamond-T’s were handsome as the company put an unusual (for a truck manufacturer) amount of effort into their product styling, which often featured enough chrome to make a contemporary Buick blush. Diamond-T wasn’t a large manufacturer and sourced their mechanical components from outside suppliers. Their gasoline engines usually came from Hercules or Continental, and their smaller trucks often used a version of the Nash 252 OHV 6. Diamond-T had a strong relationship with International Harvester, sometimes using the IH Red Diamond engines and assembling certain low volume specialty trucks for International. When International introduced their modern Comfo-Vision conventional cab in 1949 they shared the design with Diamond-T (above).

The Murty Brothers of Portland, OR. started their business in 1938. They had several patents or inventions over the years and were famous for many innovations in truck engineering, including the ‘Maxi’ type air parking brake and tandem front steering axles. They built this front wheel drive truck in 1946, the first of several low-floor trucks.

They had a successful business building specialty trucks like this narrow cab (based on a White 3000) for long loads.

In 1949 they started working on a simplified mechanical tilt cab design. Their work caught the attention of Zenon C.R. Hansen, the sales manager of the Automotive Equipment Company, a Diamond-T dealer in Portland. Up to that time Diamond-T built nothing like the White 3000, so with the blessing of the dealership and D-T president E.J. Bush, Hansen supplied the Murty Brothers with a new Diamond-T truck with which to build a prototype.

What the Murty Brothers came up with was more than a simple copy of the White 3000. It isn’t known if the Murty Brothers looked at the White 3000 all that closely, but what they came up with for Diamond-T was better in several ways. While White’s tilting mechanism was an electric screw jack similar to an aircraft landing flap actuator, the Murty design simply used 2 large coil springs to lift the cab to the halfway point where the springs were relaxed. Beyond that, the springs were stretched in the full tilt position where they assisted to lower the cab.

White’s transmission shift linkage was rather complex and used a system of shafts and U-joints to connect the floor mounted shift lever with the transmission, while the Murty design was a bit less complex and initially featured a novel steering column shift lever (5-on-the-tree!). The cab floor ahead of the driver’s seat was mounted to the chassis and didn’t tilt with the cab, so the pedal linkages were simplified.

Perhaps the most significant differences between the White and Murty designs were that the Murty cab was wider than the White’s and used bucket seats with an engine ‘doghouse’ in between. An additional seat could be mounted over the doghouse for two extra passengers. This allowed the Murty design to accommodate larger engines than the White 3000. In later years trucks that used the Murty designed cab could accommodate Cummins diesels and large gasoline V-8’s without many modifications, while White had to resort to some real engineering heroics to get a Cummins under a 3000 cab. Cummins powered 3000’s had the cab jacked up, engine tilted to the side, and the radiator and fan moved to the back of the cab. The Murty designed cab also had a larger 2-piece windshield.

The prototype Diamond-T Tilt Cab truck that the Murty Brothers built impressed everyone that saw it, and the new truck was featured at the 1953 Chicago Auto Show. Diamond-T had refined the styling of the cab from the original Murty design, and like the Comfo-Vision cab it appears the Murty cab panels were also stamped by the Chicago Manufacturing Company.

The Diamond-T Tilt Cab went on sale in 1953 in several model lines, from the 1.5 ton Nash powered 323C to the Cummins powered 723C and was an immediate success. Due in part to the success of the new truck, Zenon C.R. Hansen was offered a position in Diamond-T and eventually became president of the company.

Given the close relationship between Diamond-T and International, it was probably no surprise that International Harvester introduced their own tilt-cab trucks in 1954 featuring the Murty designed cab. The new IH CO Series truck was built on an I.H. designed chassis and powered with I.H. gasoline engines, but surprisingly the trucks were assembled by Diamond-T. By 1956 I.H. was offering their large displacement gasoline V-8’s and Cummins diesels in the CO series, along with tandem axle models. Like the D-T Tilt Cabs, the IH CO Series proved to be quite popular. In 1957 Ford introduced their low-cost C Series tilt-cab trucks, which featured a licensed copy of the Murty coil spring tilt mechanism.

In 1958, Diamond-T was bought by White. The move surprised a lot of people in the automotive industry as there was considerable product overlap between D-T and White, which by that time also owned Autocar and REO. Obviously the White 3000 competed directly with the D-T Tilt Cab as just one example. The deal ended any further cooperation between D-T and International Harvester, though the agreement IH had to use the Murty designed cab did continue. D-T discontinued the use of the Comfo-Vision cab and replaced it with Autocar and REO cabs. D-T also stopped assembling trucks for IH.

As White integrated Diamond-T and REO into their organization, there was consolidation of various competing truck models. Many of D-T’s medium duty conventional cab trucks were replaced by re-badged REO’s, and REO began to market re-badged D-T Tilt Cabs. REO’s highly regarded gasoline engines replaced other gasoline engines in D-T trucks. These moves were facilitated by the closure of Diamond-T’s Chicago plant and consolidation of all D-T and REO production at REO’s plant in Lansing MI. It was during this time Zenon C.R. Hansen became executive vice president of White Motors.

By 1960 trucks using the Diamond-T tilt cab had become a common sight, particularly the IH CO due to International’s production capacity and vast dealer network. Nonetheless, the various Diamond-T and REO models were selling well too, and the White-owned brands introduced new features to their tilt-cab models. Most interesting was a full fiberglass cab option which was over 200 lbs lighter than the steel version. Other than a slightly different grille and contemporary ‘quad’ headlights, the fiberglass cab looked virtually identical to the steel version. The new Detroit Diesel 6V-53 and the REO Gold Comet gasoline V-8 were added to the option list. International, D-T and REO all introduced sleeper cab versions, which were notable in that they were only a few inches longer than the standard cab.

The truck on the right is equipped with the sleeper cab.

The Murty designed tilt cab also caught the attention of the Hendrickson Manufacturing Company. Hendrickson is perhaps best known for their heavy truck and trailer suspension systems, but for many years they built specialized trucks often using the Comfo-Vision cab. Hendrickson built a raised D-T tilt cab truck using the Murty cab with a set-forward front axle, possibly as a prototype for an over-the-road truck similar in concept to what Freightliner was building. Diamond-T eventually developed their own ‘high cabover’ (often referred to as a ‘China Closet’ by drivers due to its appearance) but Hendrickson went on to manufacture their own over-the-road high cabover using a modified Murty cab with sheet metal likely supplied by Chicago Manufacturing. Some of these Hendrickson cabovers were built with Detroit 12V-71 diesels for Cooper-Jarrett Freight Lines (above), who used them for pulling ‘Turnpike Doubles’ (twin 40′ tandem axle trailers) on the New Jersey Turnpike.

In the late 50’s International introduced a new line of ‘Emeryville’ high tilt cabs, using quite a bit of the sheet metal from the Murty design cab. These new ‘DCO’ model trucks looked very similar to the large Hendrickson’s. Initially they featured Cummins diesels but soon Detroit Diesels were added to the option list, marking the beginning of Detroit availability in non-G.M. trucks. The DCO cab was offered in 3 lengths, a day cab and two sleeper models, and featured a hydraulic tilting mechanism.

I.H. even went on to develop an Emeryville conventional cab over-the-road truck that also used Murty design sheet metal. The result looked a little odd (drivers often referred to it as a ‘Donald Duck International’), but the cab was very roomy and had excellent visibility.

By the mid-60’s four makes of trucks were being sold with Murty designed cabs, and trucks so equipped were a very common sight across the nation. In 1967 White merged Diamond-T and REO, creating Diamond-Reo. By that time the tilt-cab trucks from each make differed only in badging so the only changes were new model numbers and ‘Diamond-Reo’ nameplates. Diamond-Reo continued to offer the fiberglass cab option and the REO gasoline engines with a propane fuel option, along with various Cummins diesels. At some point the column shift gave way to a more conventional shift lever next to the driver’s seat. International also made some changes the CO Series, such as the addition of their new DV-550 diesel V-8’s to the option list. I.H. also came up with a clever 4 man crew cab option. With a lower engine ‘doghouse’ made possible by using the Loadstar’s smaller 345 V-8, I.H. was able to mount a bench seat behind the driver and passenger seats.

Despite the consolidation of Diamond-T and REO, White found itself with too many truck makes and models by the early 70’s. The decision was made to spin off Diamond-Reo and it was sold to Francis Cappaert in 1971, but the operation declared bankruptcy in late 1974. The Murty designed tilt cab models appear to have stayed in production at least through 1971. Diamond-Reo had designed a new ultra-modern LCF tilt cab truck named the Rouge as a replacement, but only a handful were built before the bankruptcy. Subsequently Diamond-Reo was revived on a small scale by a former dealer in Pennsylvania but they only manufactured a line of heavy-duty conventional cab trucks.

International’s CO series continued in production until 1974, despite the introduction of larger versions of the CO Loadstar/Cargostar a few years earlier which essentially made the old CO Series redundant. This marked the last use of the Murty designed cab as the Emeryville trucks had been replaced years earlier by the Transtar Series. I was unable to find any definitive information on the production of Hendrickson cabovers that used the Murty designed cab, but I think it’s safe to say that none were built after the late 60’s. So, there you have it: The story behind an innovative truck cab that was designed by pioneering Murty brothers, discovered by the legendary Zenon C.R. Hansen, put into production by the venerable Diamond-T Company, and was successfully used by three other truck manufacturers for 21 years. As for Zenon C.R. Hansen, he left White in the early 60’s to turn around floundering Mack Trucks after Chrysler’s failed attempt to buy them out. He succeeded beyond all expectations, and when he retired in 1974, Mack had never been so successful. One wonders what would have happened had Hansen not seen the potential in the Murty Brother’s cab design.