Entering production in 1950, the new heavy-duty L-series had new styling, with the wide Comfo-Vision cab and a blunt, squared-off nose instead of the narrow, rounded, nose of the old KB-series heavies. The new trucks were powered by big-block Super Red Diamond 6-cylinder gasoline engines that were upgraded from the Red Diamond engines of the KB-series.
The L-185 was an odd model designation. It was theoretically the Roadliner tractor model in the L180-series, and yet it was obviously part of the heavy-duty L-series and bore little resemblance to the L-180 Standard and Loadstar models. With its 42000 lb GCW rating, the L-185 was basically a replacement for tractor versions of the KB-8, with the engine increased from 361 to 372 ci and from 126 to 144 hp. The L-185 was roughly comparable to the GMC HCR-620 (40,000 lb GCW, 360 ci, 150 hp), and the Ford F-8 (337 ci, 145 hp).
When the updated R-185 came out in 1953, the only significant styling change was the use of three vertical bars in the upper grille instead of the seven of the L-series. Mechanically the trucks were almost unchanged. In 1955 engine refinements boosted the output of the RD-372 engine to 165 hp. In 1956 the 175-hp RD-406 was made optional in the R-185 model. In 1959 the 18500 lb rear axle that was standard in the R-190 series was made optional in the R-185. With that and the optional 7000 lb front axle, the maximum GVW rating was increased to 25,500 lb in 1961 and the GCW went up to 50,000 lb. In 1964 the R-185 and all R-series heavy trucks were fitted with large rectangular turn signals on the tops of the fenders. Also that year the RD-450 engine became available in the R-185 tractor and, in mid-year, the RD-501 was added. In 1965 higher compression ratios boosted engine power to 193-hp for the RD-406, 199-hp for the RD-450, and 215-hp for the RD-501. At the same time the Allison 6-speed automatic was made available.
- International L-185 Truck
- International R-180 Series
- International Trucks
- International Harvester
- Navistar International
References / sourcesEdit
- Crismon, Frederick W. (1995). International Trucks. Motorbooks International, Osceola, Wisconsin.
- Mroz, Albert (1996). The Illustrated Encyclopedia of American Trucks and Commercial Vehicles. Krause Publications, Iola, Wisconsin.
- Hays Antique Truck Museum, Woodland, California
- Heidrick Ag History Center, Woodland, California
- American Truck Historical Society
- International Trucks
- Navistar webpage