Skip to content

Types Of Chassis Frame | Here’s What No One Tells You About 7 Awesome Things You Can Learn From Studying Auto Chassis


Chassis frame is a part of automobile body structure, which is the backbone of the structure and the basis of all parts of vehicle body structure, it plays a very important role in automobile body structure


There are three types of chassis frames and they are listed below. The Automobile chassis frame is exposed to both bending and torsional distortion during vehicle travel over typical ground surfaces. The various chassis-member cross-section forms that find use under certain running conditions include.
1. Conventional frame
2. Integral frame
3. Semi-integral frame

01-ladder frame chassis-chassis liner frame chassis-automobile chassis-tube frame chassis-chassis kits-types of chassis frames

1. Conventional frame:

It has two long side members and 5 to 6 cross members joined together with the help of rivets and bolts. The frame sections are used generally.

a. Channel Section – Good resistance to bending
b. Tubular Section – Good resistance to Torsion
c. Box Section – Good resistance to both bending and Torsion

2. Integral Frame:

This frame is used now a days in most of the cars. There is no frame and all the assembly units are attached to the body. All the functions of the frame carried out by the body itself. Due to elimination of long frame it is cheaper and due to less weight most economical also. Only disadvantage is repairing is difficult.

3. Semi – Integral Frame:

In some vehicles half frame is fixed in the front end on which engine gear box and front suspension is mounted. It has the advantage when the vehicle is met with accident the front frame can be taken easily to replace the damaged chassis frame. This type of frame is used in some of the European and American cars.

02-custom car chassis-rigid car frames-space frame chassis-chassis frame design-carbon fibre chassis

What exactly is a frame?

The frame is the most important aspect of the chassis, on which the other components are placed. The frame should be highly stable and solid in order to withstand the shocks, bends, stresses, and vibrations that the vehicle experiences when on the road.

The wheels and tyre arrangements are supported by the frame. The front of the frame is small to allow for a small turning circle for the front wheels. It widens out at the back to have more cabin space.

01-types of chassis frames - auto chassis- conventional frame-integral frame-semi integral frame

Difference between Chassis and Frames

Chassis: A vehicle’s chassis is the bare minimal design that allows it to move, such as a frame that is equipped with an engine, tyres, axles, steering, and brakes, among other things. The skeleton structure of a vehicle that has been equipped with the majority of its mechanical components.

Frame: The frame of a vehicle serves as the vehicle’s body, with all other pieces linked to it (either with bolts, rivets, or welds) by means of the frame. The chassis is fastened to the frame via bolts.

Read More:   Pneumatic Braking System In Automobile | Air Braking System | Construction And Working Of Pneumatic Braking System

Side Members and Cross Member Construction of Chassis Frames

The frame side-members that cross the wheelbase between the front and rear axles must be capable of supporting the full amount of sprung weight. The weight of the portion of the vehicle covered by the suspension structure is referred to as the sprung weight. These members’ binding stiffness must be able to withstand their inherent inclination to drag. The use of open-channel pressed sections or thin-walled hollow round or rectangular sections may provide the maximum bending stiffness of the frame members compared to their weight.

A 4 mm C-section channel with a channel web-depth ratio of around 3:1 is generally used as a side chassis member. This gives a 15-fold bending resistance to the same cross-sectional area as the solid square section.

Two C-section channels may be mounted to establish a rigid load-supporting member for heavy-duty applications. The side members could have a dual-section channel to provide additional strength and support to the existing chassis across a highly loaded place.

01-types of chassis frames - sub-frames-side members and cross members of automobile chassis

What exactly are Sub-Frames?

A motor vehicle’s various parts are bolted directly to the frame’s mainframe members or cross members. However, the engine and gearbox are often mounted on a simple sub-frame. The mainframe normally supports the sub-frame at three points. The aim of this design is to protect such modules from the mainframe’s twisting and bending.

Types of chassis frames according to the engine’s mounting position:

• Engine mount in front

• Engine mount in front yet crosswise

• Engine mount in the middle of the chassis

• Engine mount in the back of the chassis

Front-mounted engine / Engine mounted in front:

Traditionally, engines are mounted in the front and drive is delivered to the wheels from the back. The following are some of the benefits of this type: There is enough room for luggage behind the back seat; the weight of the cars is evenly distributed; the cooling system is more efficient;

The engine is mounted in the front, but it is installed crosswise:

There is a low-floor option. The vehicle has a greater potential for load-carrying capacity. The clutch, gearbox, and differential are normally built as a single unit to save money.

The engine is mounted in the middle of the chassis:

As in Leyland Royal Tiger World Master buses, simply known as Leyland Worldmaster historically piled by, the drive is provided to the rear. This structure provides maximum floor space for use.

The engine is mounted in the rear of the vehicle.

This drive uses a real engine, and the cars that use it are called dolphins. The benefits include: A flat floor is possible due to the absence of long propeller shafts; The centre of gravity is reduced, resulting in stable driving; Better adhesion on the ground, especially while climbing hills.

Read More:   Construction and Working of Pistonless Pump | Pistonless Pumps in Aerospace Technology

The drawbacks are as follows: When climbing hills, adequate adhesion can be compromised because the vehicle’s weight shifts to the rear, decreasing the weight on the front wheel; Since the transmission, clutch, gearbox, and differential are all grouped together, repairing and adjusting them becomes complicated.


What do you mean by Auto Chassis?

The chassis frame of an automobile serves as the structural framework for the whole vehicle. The chassis of an automobile is responsible for keeping the vehicle on the road and for keeping the occupants safe within the vehicle. The word “chassis” refers to all of the pieces of a vehicle that are not part of the body work. The chassis refers to the grouping of the key components of a vehicle. It comprises components like as wheels, brakes, suspension systems, axles, and the engine.

How many types of car chassis are there?

There are three types of chassis frames and they are listed below. The Automobile chassis frame is exposed to both bending and torsional distortion during vehicle travel over typical ground surfaces. The various chassis-member cross-section forms that find use under certain running conditions include.
1. Conventional frame
2. Integral frame
3. Semi-integral frame

What does the frame of a car do?

The primary roles of a frame in a motor vehicle are as follows: to sustain the mechanical components and body of the vehicle. To withstand both static and dynamic stresses without experiencing excessive deflection or distortion.
The traditional method of making vehicles began with a frame, which was a type of ladder-looking structure consisting of steel rails and crosspieces. After that, everything was fastened to that foundation. Axles, engine, and drive train are all examples of mechanical components. Then there’s the body. This kind of construction is still often used for heavier vehicles.
Nowadays, the majority of passenger automobiles are constructed using the body as a structural component. Axles, engine, and drive train are generally bolted directly to the body instead of being welded. It reduces the amount of material used, the weight of the assembly, and the amount of time required.

What are sub frames in automobiles?

When a car is built, the different pieces of the vehicle are attached directly to the frame’s mainframe and cross members. The engine and gearbox, on the other hand, are often installed on a basic sub-frame. The mainframe generally provides three sources of support to the sub-frame. The purpose of this design is to shield such modules from the twisting and bending caused by the mainframe.

How important is the frame in an automobile?

The chassis frame is a component of the automotive body structure, serving as the structure’s backbone and the foundation for all other components of the vehicle’s body structure. It is critical to the overall construction of the vehicle. From the name itself we can understand the importance. Hope you understand from the above explanations.

How is a car frame made?

Early frames were often made of two parallel rails that went bumper to bumper and were connected together by two or more cross members to form a single structure. Steel channel or box tubing are positioned parallel and apart according to the design of two pieces of steel channel or box tubing, which may be as long as required for your design. After that, more sections of channel or box are cut and either riveted or welded together to keep everything together. In the past, this kind of assembly has been known as a ladder frame because it has a similar appearance to a ladder, however with irregular spacing between the “steps.”
Afterwards, in the 1970s, the Uni-body was developed, which was essentially a box for each axle affixed to the proper end of the cabin compartment between the fenders, with the intermediate structure being reinforced bodywork. Nowadays, automobiles are composed of both frame and body components.

Which factors are to be considered for car frame design?

The following are some critical things that must be kept in mind:
1. Composite Monocoque or Tubular space frame design for the chassis.
2. Material Considerations for the Chassis – While aluminium is not as robust as steel, it is much lighter. Its rigidity is about one-third that of steel; nevertheless, it is approximately one-third the weight of steel. Steel, the most often used material for tubular space frames, keeps its strength and ductility even after being welded together.
3. There are five fundamental load cases resulting from typical operating circumstances.   Bending loading – Torsion loading – Combination of bending and torsional loading – Lateral  Loading– Loading from the front and rear
4. Inertia loading of the structure adds to overall loading; Inertial loading is always larger than static loading; longitudinal loading is formed when the vehicle accelerates and decelerates. These inertial loading and longitudinal loading are the parts of dynamic loading.
5. If the car traverses an uneven road, t he front and rear axles are subjected to a moment referred to as Lateral loading.
6. Asymmetric loading occurs when one wheel impacts a raised obstacle or falls into a pit while the other wheel does not.

Identify which is not a type of frame
1. Integral frame
2. Semi – Integral frame
3. Half – Integral frame
4. Conventional frame

Answer: Half Integral frame

1 thought on “Types Of Chassis Frame | Here’s What No One Tells You About 7 Awesome Things You Can Learn From Studying Auto Chassis”

  1. Pingback: 15 Placement Interview Questions In Mechanical Engineering | Every Technical Interview From A Mechanical Engineering Graduate’s Point Of View. | BlogMech

Leave a Reply