Vehicle Construction

Question 1

What five parts comprise the chassis

Answer 1

Frame, engine, suspension system, steering, mechanical parts (with the body removed)

Question 2

body over frame means

Answer 2

body bolted to thick steel framework

Question 3

unibody construction means

Answer 3

body parts welded or adhesive bonded together to form a frame

Question 4

front clip is…

Answer 4

front bumper to firewall.

Question 5

rear clip is…

Answer 5

rear bumper to trunk

Question 6

the cowl is…

Answer 6

the panel at the rear or the front section right in front of the windshield. covers gap between hood and windshield or trunk and windshield.

Question 7

what does a rocker panel do

Answer 7

On unibody automobiles where the body and frame of the vehicle are one, rocker panels provide the structural reinforcement that keeps the bottom of the vehicle from sagging in the middle. They are normally welded to the floor pan and pillars, kickpanels or quarter panels.

Question 8

what are cross members and what do they do?

Answer 8

A cross member is a structural component of a car, normally made of steel and bolted across the underside of the vehicle. As well as supporting the engine and transmission of the car and keeping body panels aligned, it aids the suspension system by maintaining stability.

Question 9

what is a crush zone

Answer 9

areas in unibody that are intentionally made weaker to collapse during a collision and absorb some of the impact and redistribute around the passenger cabin.

Question 10

what is a floor tunnel?

Answer 10

in front engine, rear wheel drive vehicles, the tunnel for the transmission and drive shaft.

Question 11

longitudinal vs transverse engine placement?

Answer 11

perpendicular vs. parallel to axles.

Question 12

what is torque steer?

Answer 12

engine torque is transmitted into the steering wheel under hard acceleration.

Question 13

what is the area between the back glass and trunk lid called?

Answer 13

upper rear panel.

Question 14

where are rocker to rail braces located?

Answer 14

between rocker panel and frame rail.

Question 15

many small pickups have what types of frames?

Answer 15

bolt on removable stub frame under the engine.

Question 16

what are unibody torque boxes

Answer 16

allow controlled twisting and crushing of structure during severe collisions. They also secure passenger compartment to frame rails.

Question 17

front engine, front wheel drive vehicles combine what two parts and eliminate what one part?

Answer 17

combine transmission and differential into a transaxle, and eliminate drive shaft.

Question 18

what type of engine and drive handles snow best and why? FF, FR, MR

Answer 18

front engine, front wheel drive, FF becaues there is more engine and transaxle weight over the drive wheels.

Question 19

what does a differential do?

Answer 19

drive a pair of wheels while allowing them to rotate at different speeds

Question 20

what does a transaxle do? what configuration is it common in?

Answer 20

universal when the engine and drive wheels are on the same side of the car.

operation of any transaxle is exactly the same as that of any transmission. The difference is this: Instead of being connected via a long driveshaft to the rear axle, the transmission drives a large gear that meshes directly with the differential’s ring gear. The differential itself (which would be mounted on the rear axle in a rwd car) is located in the transaxle housing, mounted parallel to the transmission. As power is applied, the differential distributes it to the two front wheels via half-shafts.

Question 21

what is a composite unibody? AKA space frame?

Answer 21

made of special plastics and or carbon fiber adhesive bonded/structurally glued to each other. the use if lightweight plastics nd carbon fiber lowers total vehicle wehight for better performance and fuel economy

Question 22

what 3 parts of a unibody keep passengers safe during a collision

Answer 22

crush zones, torque boxes and cross members.

Question 23

what is one disadvantage of unitized vehicle design?

Answer 23

the damage is not localized to components, but spread

Question 24

how does rack and pinion steering work?

Answer 24

round toothed gear from the steering wheel is attached to a toothed linear bar. the teeth pull the rack the direction you’d like to turn. Rack attached to tie rods, then to the steering control arms then to the hub.

Question 25

benefits of unibody construction

Answer 25

more rigid due to the forces spreading over the entire vehicle. 
less material
lighter
better fuel economy
handling
acceleration
deceleration.

Question 26

what is designed to stiffen a unibody structure?

Answer 26

cross members and bracing

Question 27

what is the purpose of a frame horn

Answer 27

Cast iron “horn” is a spring hanger as well as a connection for front bumper braces. These horns are securely riveted into the end of the frame. Usually the whole frame can bend before the cast iron horn breaks.