Early on, Scammell considered alternative engine and driveline combinations for the Crusader 6x4. As well as the Detroit two-stroke 8V-71N, which became standard, it was planned to offer the Cummins V8- 903 with a gross output of 300bhp at 2600rpm. Both were to be aimed primarily at the overseas market while, for UK buyers, Scammell decided to offer the ill-fated AEC V8 with a 250bhp net output.
The AEC V8 was coupled to an existing Thornycroft-built AEC 10-speed range-change gearbox designed by Edward Riddle. A few were built with this spec, including one for appraisal by Bass Charrington, and another for exhibition at the 1969 Scottish Show. One operator to run an AEC V8
