Trucks can use all sorts of engines. Small trucks such as SUVs or pickups, and even light medium-duty trucks in North America and Russia will use gasoline engines. Most heavier trucks use four stroke turbo intercooler diesel engines, although there are alternatives. Huge off-highway trucks use locomotive-type engines such as a V12 Detroit Diesel two stroke engine.

North American manufactured highway trucks almost always use an engine built by a third party, such as CAT, Cummins, or Detroit Diesel. The only exceptions to this are Volvo Trucks and Mack Trucks, which are available with subsidiary of DaimlerChrysler, which are available with Mercedes-Benz and Detroit Diesel engines. Trucks and busses built by the Navistar International can also contain International engines. The Swedish truckmaker Scania claims they stay away from the U.S.-market because of this third party tradition.

In the European union all truck engines must comply with Euro 4 regulations, the regulations will become more severe in  with the introduction of Euro 5.

 

                     

There are standard tests for safety in new automobiles, like the EuroNCAP and the US NCAP tests.There are also tests run by organizations such as IIHS and backed by the insurance industry.

Despite technological advances, there is still significant loss of life from car accidents: About 40,000 people die every year in the United States, with similar figures in European nations. This figure increases annually in step with rising population and increasing travel if no measures are taken, but the rate per capita and per mile traveled decreases steadily. The death toll is expected to nearly double worldwide . A much higher number of accidents result in injury or permanent disability. The highest accident figures are reported in China and India. The European Union has a rigid program to cut the death toll in half by and member states have started implementing measures.

Automated control has been seriously proposed and successfully prototyped. Shoulder-belted passengers could tolerate a 32 g emergency stop (reducing the safe inter-vehicle gap 64-fold) if high-speed roads incorporated a steel rail for emergency braking. Both safety modifications of the roadway are thought to be too expensive by most funding authorities, although these modifications could dramatically increase the number of vehicles able to safely use a high-speed highway. This makes clear the often-ignored fact road design and traffic control also play a part in car wrecks; unclear traffic signs, inadequate signal light placing, and poor planning (curved bridge approaches which become icy in winter, for example), also contribute.