THE Prado's four-cylinder, cast-iron block, 3.0-litre turbo-diesel engine uses plenty of modern technology - such as a drive by wire electronic throttle and a water-cooled turbocharger - but is not the most highly developed 4WD turbo-diesel. It uses an alloy head, twin balance shafts for smoothness and an air-to-air intercooler to maximise intake charge efficiency, but has a single overhead camshaft with just two valves per cylinder, where some of its competition is using twin camshafts and multi valves. Outpointed by Nissan's latest four-cylinder turbo-diesel in output, it still produces more torque than Toyota' 3.4-litre V6 petrol engine. Because of the high compression ratio, each engine has an individually tailored head gasket to eliminate the risk of pistons protruding above the cylinder block deck. The engine was modified for Australia with a new cylinder head alloy, new combustion chamber design, a larger radiator, a new air-conditioning condenser and modified engine management.