# Subframe

> Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Subframe
> Markdown URL: https://mediated.wiki/source/Subframe.md
> Source: https://en.wikipedia.org/wiki/Subframe
> Source revision: 1341361012
> License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/)

{{Short description|Vehicle component}}
[[Image:Lamborghini Aventador LP 700-4 chassis - Flickr - J.Smith831.jpg|thumb|260px|The [Lamborghini Aventador](/source/Lamborghini_Aventador) has a carbon fibre central monocoque, with front and rear steel subframes, mounting the mechanics.]]
[[File:VectraFrontSubframeBMuseum.JPG|thumb|upright|Front subframe of a [Vauxhall Vectra](/source/Opel_Vectra) on display in [Bedford Museum](/source/Bedford_Museum_%26_Art_Gallery)]] 
thumb|Animation showing the location of Vehicle Subframes in a CAD Vehicle.
A '''subframe''' is a structural component of a vehicle, such as an [automobile](/source/Car) or an [aircraft](/source/aircraft), that uses a discrete, separate structure within a larger [body-on-frame](/source/body-on-frame) or [unibody](/source/Monocoque) to carry specific components like the [powertrain](/source/powertrain), [drivetrain](/source/drivetrain), and [suspension](/source/Suspension_(mechanics)). The subframe is typically [bolted](/source/Bolt_(fastener)) or [welded](/source/Welding) to the vehicle. When bolted, it often includes [rubber bushings](/source/rubber_bushings) or [springs](/source/Spring_(device)) to dampen [vibrations](/source/vibrations).<ref>{{cite web |title=Subframes & Engine Cradles |url=https://www.aec.org/page/subframes-engine-cradles |access-date=25 June 2022 |website=Aluminum Extruders Council}}</ref><ref>{{Cite web |date=2023-08-03 |title=What You Need to Know About Subframe Repair |url=https://www.carparts.com/blog/what-you-need-to-know-about-subframe-repair/ |access-date=2024-07-10 |website=CarParts.com}}</ref><ref>{{Cite web |last=Kilchermann |first=Lori |date=2024-05-23 |title=What is a Subframe? |url=http://www.wikimotors.org/what-is-a-subframe.htm |access-date=2024-07-10 |website=WikiMotors.com}}</ref>

The primary purposes of using a subframe are to distribute high chassis loads over a wide area of relatively thin [sheet metal](/source/sheet_metal) of a monocoque body shell and to isolate vibrations and harshness from the rest of the body. For example, in an automobile with its powertrain contained in a subframe, forces generated by the [engine](/source/engine) and [transmission](/source/Transmission_(mechanical_device)) can be sufficiently damped to prevent disturbing the passengers. Modern vehicles use separate front and rear subframes to reduce overall weight and cost while maintaining structural integrity. Additionally, subframes benefit production by allowing subassemblies to be created and later introduced to the main body shell on an automated line.

There are generally three basic forms of the subframe:
# A '''simple "axle" type''', which usually supports the lower control arms and steering rack.
# A '''perimeter frame''', which supports the lower control arms, steering rack, and engine.
# A '''perimeter frame with full support''', which supports the lower control arms, steering rack, engine, transmission, and possibly the full suspension, commonly used in front-wheel-drive cars.

Subframes are typically made of pressed steel panels that are thicker than body shell panels and are welded or [spot-welded](/source/Spot_welding) together. [Hydroformed](/source/Hydroforming) tubes may also be used in some designs.

The revolutionary monocoque, transverse-engined, front-wheel-drive [1959 Austin Mini](/source/Mini_(Mark_I)) set the template for modern front-wheel-drive cars by using front and rear subframes to provide accurate road wheel control while maintaining a stiff, lightweight body. The [1961 Jaguar E-Type](/source/Jaguar_E-Type) (XKE) used a tubular space frame–type front subframe to mount the engine, gearbox, and long bonnet/hood to a monocoque "tub" passenger compartment. Beginning with the 1960s, subframes saw regular production with [General Motors](/source/General_Motors)' [X-](/source/General_Motors_X_platform_(RWD)) and [F-platform](/source/General_Motors_F_platform) bodies, and the [Astro/Safari](/source/Chevrolet_Astro) mid-size vans.

Subframes are prone to misalignment, which can cause vibration and alignment issues in the suspension and steering components. Misalignment is caused by space between the mounting bolts and the mounting hole. Several companies in the automotive aftermarket, including TyrolSport in the US and Spoon Sports in Japan, offer solutions for subframe misalignment and movement issues.

{{Multiple image
| align             = left
| image1            = 1963 Jaguar E-Type rear subframe front view.jpg
| width1            = 220
| caption1          = Rear subframe and suspension of a 1963 Jaguar E-Type
| image2            = Bodengruppe Ford Focus 2011.jpg
| width2            = {{#expr: (480 / 640 * 220 * 2390 / 1284) round 0}}
| caption2          = Underbody with front and rear subframes of a 2011 Ford Focus
}}
{{CarDesign nav}}

==References==
{{Reflist}}

Category:Automotive chassis types
Category:Auto parts
Category:Structural system
Category:Structural engineering

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Adapted from the Wikipedia article [Subframe](https://en.wikipedia.org/wiki/Subframe) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Subframe?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.