Engine

The oldest truck was built in 1896 by Gottlieb Daimler. [2] Small trucks such as SUVs or pickups , and even light medium-duty trucks 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 and its subsidiary Mack Trucks , which are available with their own engines. Freightliner , Sterling Trucks and Western Star , subsidiaries of Daimler AG , are available with Mercedes-Benz and Detroit Diesel engines. Trucks and buses built by Navistar International usually also contain International engines. The Swedish manufacturer 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 5 regulations.

[ edit ] Drivetrain

Small trucks use the same type of transmissions as almost all cars which have either an automatic transmission or a manual transmission with synchronisers . Bigger trucks often use manual transmissions without synchronisers which have less bulk and weight although synchromesh transmissions are used in larger trucks as well. Transmissions without synchronisers known as "crash boxes" require double clutching for each shift, (which can lead to repetitive motion injuries), or a technique known colloquially as "floating," a method of changing gears which doesn't use the clutch, except for starts and stops, due to the physical effort of double clutching especially with non power assisted clutches, faster shifts, and less clutch wear.

Double clutching allows the driver to control the engine and transmission revolutions to synchronize, so that a smooth shift can be made e.g. when upshifting, accelerator pedal is released and the clutch pedal is depressed while the gear lever is moved in to neutral, clutch pedal is then released and quickly pushed down again while the gear lever is moved to the next highest gear. Finally, the clutch pedal is released and accelerator pedal pushed down to obtain required engine rpms. Although this is a relatively fast movement perhaps a second or so while transmission is in neutral it allows the engine speed to drop and synchronize engine and transmission revolutions relative to the road speed. Downshifting is performed in a similar fashion except the engine speed is now required to increase (while transmission is in neutral) just a right amount in order to achieve the synchronisation for the smooth non-crunching gearchange. The so called skip changing is also widely used, in principle operation is the same but it requires neutral be held slightly longer than single gearchange.

Common North American setups include 9, 10, 13, 15, and 18 speeds. Automatic and semi-automatic transmissions for heavy trucks are becoming more and more common, due to advances both in transmission and engine power. In Europe 8, 10 and 12 gears are common on larger trucks with manual transmission, while automatic or semiautomatic transmission would have anything from 5 to 12 gears. Almost all heavy trucks transmissions are of a "range (double H shift pattern ) and split" type where range change and so called half gears or splits are air operated and always preselected before the main gears selection.

In Europe more new trucks are being bought with automatic or semi-automatic transmission. This may be due the fuel consumption can be lowered and truck durability improved. [ citation needed ] The primary reason perhaps is the fact that such transmissions give a driver more time to concentrate on the road and traffic conditions.