The DD42 was a bus made by Crossley between 1945 and 1952. The prototype was built in 1944.
The production can be broken down into multiple distinct groups depending on the engines fitted to the chassis.
- Chassis numbers 92901 to 92903. Built in 1944. The only prototype completed was 92901 completed. A 8600cc Crossley HOE7 engine was fitted.
- Chassis numbers 93201 to 93900. Built between 1945 and 1947. The buses were 7ft 6in wide and came with a 8600cc Crossley HOE7/1 direct injection engine and 251 were made.
- Chassis numbers 93901 to 94232. Built between 1947 and 1948. The DD42/4 was 8ft wide and the DD42/5 was 7ft 6in wide. They were fitted with a 8600cc Crossley HOE7/1 direct injection engine and 306 were made.
- Chassis numbers 94701 to 94799. Built between 1948 and 1950. The DD42/8 was 8ft wide and the DD42/7 was 7ft 6in wide. They were fitted with a 8600cc Crossley HOE7/4B direct injection engine and 200 were made.
- Chassis numbers 94800 to 95200. Built between 1948 and 1950. The DD42/8 was 8ft wide and the DD42/6 and DD42/7 were 7ft 6in wide. They were fitted with a 8600cc Crossley HOE7/4, 7/4B, and 7/5B direct injection engine, 300 were made.
- Chassis numbers 95301 to 95908. Built between 1950 and 1952. The DD42/8 and 8A were 8ft wide and DD42/7 was 7ft 6in wide. They were fitted with a 8600cc Crossley HOE7/5 direct injection engine and 58 were made.
The majority of DD42s had Crossley bodies but some chassis were supplied to other coachbuilders.
The engine used was the Crossley HOE7 8600cc diesel with direct injection. The engine was a 6 cylinder unit with an overhead camshaft. The HOE7/1, 2, 3 & 4 engines produced 100 bhp at 1750 rpm and the HOE7/5 engine produced 114 bhp at 1750 rpm. The buses were made in two widths. The engines could do between 7 and 11mpg.
The buses came with a range of gearboxes including a four-speed constant mesh and four-speed synchromesh. The gearboxes were mounted in unit with the engine. The buses had a dry single-plate clutch and the differencial was offset to the left on the rear axle. The chassis were fitted with semi-elliptical leaf-springs all round. Vacuum asssited were fitted to the buses as well.
There were no buses made designated DD42/2.
The chassis was priced at £1630 in 1950.