Editing Challenger 2 (section)

=== Drive system ===
[[File:The King's Royal Hussars take on Bavarian Challenge during Exercise COMBINED RESOLVE APOG-OFFICIAL-20240604-006-136.jpg|thumb|[[Royal Electrical and Mechanical Engineers|REME]] mechanic performing field maintenance on the power pack of a [[King's Royal Hussars]] Challenger 2.]]

The tank's drive system comprises:
* Engine: [[Perkins Engines|Perkins]] 26.1&nbsp;litre, 60° vee, twin turbocharged, CV12-6A four-stroke, four-valve-per-cylinder (pushrod), direct-injection [[diesel engine]] delivering {{convert|1200|bhp|kW|abbr=on}} at 2300&nbsp;rpm. Torque 4126&nbsp;Nm at 1700&nbsp;rpm.<ref>https://www.thefreelibrary.com/building challenger 2.-a09038700</ref> The engine and gearbox are controlled by a Petards Vehicle Integrated Control System (VICS).<ref>{{cite web |url=http://www.petards.com/our-solutions/defence-services/control-systems |title=Control Systems |publisher=Petards Group |access-date=10 March 2018 |archive-url=https://web.archive.org/web/20180313031444/http://www.petards.com/our-solutions/defence-services/control-systems/ |archive-date=13 March 2018 |url-status=live}}</ref>
* Gearbox: [[David Brown Limited|David Brown]] Santasalo TN54E epicyclical transmission (6 fwd, 2 rev.) rated at 1200&nbsp;bhp and upgradable to 1500&nbsp;bhp.<ref>{{Cite web |url=https://dbsantasalo.com/industries/defence/land-defence/tn54-tracked-vehicle-transmission/ |title=TN54E Tracked Vehicle Transmission |access-date=19 February 2018 |archive-url=https://web.archive.org/web/20180220033059/https://dbsantasalo.com/industries/defence/land-defence/tn54-tracked-vehicle-transmission/ |archive-date=20 February 2018 |url-status=live}}</ref>
* Suspension: Horstman Defence Systems second-generation [[Hydropneumatic suspension|hydrogas]] suspension units (HSU).
* Track: William Cook Defence hydraulically adjustable TR60 414FS double-pin.<ref>{{cite web |url=https://www.william-cook.co.uk/gb/news/cook-defence-systems-is-track-supplier-of-choice-at-dsei-2019 |title=Cook Defence Systems is track supplier of choice at DSEI 2019 |publisher=William Cook |date=10 September 2019 |access-date=7 January 2020}}</ref>
* Maximum speed: {{convert|37|mph|km/h|abbr=on}} on road; {{convert|25|mph|km/h|abbr=on}} cross country
* Range: {{convert|342|mi|km|abbr=on|disp=or}} on road with external fuel; {{convert|156|mi|km|-1|abbr=on}} cross country on internal fuel.

The tank is fitted with an Extel Systems Wedel auxiliary power unit, an APU, also referred to as a generating unit engine (GUE), based on a 38&nbsp;kW Perkins P404C-22 diesel engine. It has a 600&nbsp;A electrical output, which can be used to power the vehicle's electrical systems when it is stationary and the main engine is switched off. This replaces the Perkins P4.108 engine fitted when the tank was first introduced.<ref>{{cite web |url=http://ted.europa.eu/udl?uri=TED:NOTICE:411049-2016:TEXT:EN:HTML&src=0 |title=Repair of Challenger 2 ESW APU |publisher=Official Journal of the EU |date=22 November 2016 |access-date=8 March 2018 |archive-url=https://web.archive.org/web/20180310010421/http://ted.europa.eu/udl?uri=TED:NOTICE:411049-2016:TEXT:EN:HTML&src=0 |archive-date=10 March 2018 |url-status=live}}</ref> The use of an APU allows fuel consumption to be reduced, and lowers the audio and thermal signature of the vehicle.

By 2013 the British Army had, at various events featuring the Challenger 2, begun to state the on-road range as 550&nbsp;km as opposed to an earlier stated value of 450&nbsp;km.<ref name="youtube.com"/> They also publicly stated a maximum road speed of 59&nbsp;km/h while equipped with 15&nbsp;tons of additional modules.<ref name="youtube.com"/>