Excellent vehicle dynamics and high durability, quality, and reliability (DQR) all start with a well-made body assembly. Nissan uses several types of body construction based on how the vehicle is likely to be used –
With unibody construction, the actual frame of the vehicle is part of the body that forms a single structure. There is no separate frame.
By welding all the body panels together, it is possible to build in strength and rigidity without the added weight of a separate frame.
To help isolate noise and vibration from the passenger compartment, many Nissan unibody vehicles also incorporate one or two subframes — usually welded steel or cast/welded aluminum frames that support the engine and suspension, and are bolted to the front and/or rear of the unibody using specially designed mounts that isolate noise and vibrations.
Unibody vehicles tend to be lighter and more structurally rigid than vehicles built using body-on-frame construction. The stiff structure allows the suspension to control wheel movement more precisely for improved dynamic performance. At the same time, the stiff structure allows the use of softer suspension settings to increase ride comfort without compromising dynamic performance.
BODY ON FRAME CONSTRUCTION –
All pickups and certain SUVs are built using a rugged body-on-frame construction. With this process, the frame is the structural component of the vehicle. All mechanical items such as the engine and transmission along with all suspension components are firmly attached to the frame. The body of the vehicle is then attached to the frame as well but it has little to do with any of the load-bearing characteristics of the vehicle.
Specially tuned body mounts are used to attach the body to the frame and are designed to filter out certain noises and vibrations so they don’t transfer into the cabin.
Body-on-frame construction is generally used in vehicles intended for heavy-duty use because it provides a strong backbone for towing and hauling. It generally allows a greater towing capacity because the item being towed can be attached directly to the frame, not to the sheet metal, body, or bumper.
Welded Ladder Frame
All our body-on-frame vehicles feature a welded ladder frame with full-length box section rails (enclosed on all four sides). In addition, all crossmembers are welded, not riveted, to help resist flexing and increase durability.
Some competitors use open-channel frame designs behind the engine area and crossmembers that are riveted in place.
Nissan’s world-class frames have several advantages over partially boxed frames with riveted crossmembers, including:
- 30% more welds for added strength
- More crossmembers for greater rigidity
- Post-weld piercing so that all suspension and body locating points are at the exact same locations all the time
- Less NVH (noise, vibration, harshness)
- Enhanced crash performance and long-term durability
- Greater resistance to flexing so the suspension can be tuned for a smoother ride
Development, Manufacture, and Assembly
These highly advanced frames are built by Tower Automotive, which built plants adjacent to Nissan’s plants in Smyrna, Tennessee, and Canton, Mississippi.
Tower’s world-class robotic welding capabilities produce very high quality welds. Daily inspections and special tests ensure the quality of the frames. Approximately 400 features are measured on each frame, making ours among the tightest-tolerance frames built.
Also, the holes used to attach suspension components are hydraulically pierced after the frame has been welded. The process ensures consistent accuracy when attaching suspension components because the hole locations will not be altered by heat from welding.
LIGHTWEIGHT BODY COMPONENTS
Lightweight body components are used on several vehicles to help reduce overall vehicle weight. For example:
- Some liftgates are made from two layers of advanced plastics, but include a steel ring located between the two layers to create strength and rigidity.
- Certain vehicles have composite radiator supports.
- Select vehicles have aluminum-alloy hoods, trunk lids, and/or door assemblies.
GT-R has die-cast aluminum inner door panels, rear seatback structure, and front strut housing. Weight is further reduced by using a carbon-composite driveshaft, carbon-composite radiator core support, magnesium oil pan, polypropylene front diffuser, and carbon-composite center and rear diffusers.
Stop by Nissan of LaGrange and let us show you our massive selection of Unit Body and Body on Frame Nissans. We are located in beautiful LaGrange, GA.