Rapid development in technology combined with advanced software are slowly starting to blur the lines between vehicle genres these days. We are seeing an increase in Large SUV’s and UTE’s being developed with Unibody chassis. We are seeing hybrid chassis which incorporate Ladder frames with Unibody structures in luxury high-end SUV’s. Manufactures need to strike a fine balance between safety and robustness since vehicles are expected to fulfil a variety of roles these days. Occupant’s safety along with eco-friendly fuel economy across all vehicle genres are manufactures number 1 priority. With that being said, we are now finding advanced safety features in UTES that rival the best luxury sedans. Utes are becoming more refined and safer every day. Gone are the days where UTES where only used as trade vehicles.
Are Utes with ladder frame chassis safer than Cars with Unibody Structures? The simple answer is, YES. Modern Ladder Frame Pickups are incorporated with all the safety features that monocoque cars have. They also have physics on their side since their weight and height are an advantage when impacting smaller cars. Studies have found heavier vehicles to push lighter, smaller vehicles backward during an impact resulting in less force being applied to the heavier vehicle passengers over the smaller car passengers. This results in higher occupant deaths in smaller cars when impacting Ladder Frame Vehicles.
The size difference between a ladder frame pickup vs a monocoque car is vastly different. Sometimes they can weigh in excess of a ton more than a small car. Where the impact occurs on the vehicle is also critical. A small car that impacts a pickup from the side will impact mainly with the chassis of the pickup since the car is lower to the ground. In this instance the pickup occupants are safer since they are higher up and the vehicle takes most of the impact. If, however, a ladder frame pickup impacts a small car from any angle, the occupants of the smaller car will be at much higher risk since the pickup is higher and the impact will be at occupant level or higher up on the doors in the small car.
Studies have also shown that occupants of cars are more likely to be killed when impacting large SUV’s.
Monocoque SUV vs Body On Frame Pickup
This is a different scenario
all together with a monocoque SUV impacting a ladder frame Pickup. The safety
advantages of a SUV monocoque chassis vastly outweighs a ladder frame chassis. In
this instance the SUV also has physics, safety features as well as technology
on its side.
Manufactures are able to keep the centre of gravity lower with the SUV’s monocoque structure thus decreasing the chances of vehicle roll-overs. Crumble zones are integrated into the framework of a monocoque chassis to make the frame bend and fold in a specific manner that deflects the impact away from the occupants, thus making the cabin safer.
- Ladder frames are robust and rigid and their whole purpose is NOT to bend and fold under pressure. A negative when it comes to vehicle collisions.
- Certain parts of the monocoque structure can be reinforced to keep passengers safer.
- Rear and side structures of a monocoque can be specifically designed to maintain the structural integrity of the cabin in the event of a rear or side impact, all designed to safeguard the occupants.
- The frame is also designed to absorb the impact a lot better.
- All these factors are reasons why a ladder frame chassis vehicle will never be as safe as a monocoque.
Ladder frame vehicles such as modern pickup trucks like the Ford Ranger, VW Amarok and Nissan Navara have all incorporated safety features like airbags, ESP, Lane Keep Assist, Emergency Braking, advanced technology in the vehicles bonnet design to allow it to absorb impact better and Stability Control to name a few. These are all incorporated to improve the safety of a ladder frame pickup. IT will however never be as safe as a Monocoque SUV.
What is a Body On Frame Chassis?
The Ladder frame chassis is a robust metal framework consisting of two large metal beams joined together by shorter support beams in between. With a Ladder frame chassis the body and engine of the vehicle is mounted on top of the ladder frame making it a robust structure ideal for Commercial Trucks, SUV’s and 4×4 Utes that are meant to carry heavy loads for extended periods.
What is a Monocoque Chassis?
With the Monocoque design the chassis is forged into the basic structure of the vehicle creating one singular object known as a Uni-body, or Monocoque. Monocoque chassis are mainly used in the production of small SUV’s, luxury sedans and hatchbacks, offering superior safety, ride dynamics and fuel economy due to its lighter framework.
Advantages of Unibody frame chassis vehicles
With advancement in technology and software the Unibody has become much easier to design, and modify.
- It offers better ride comfort and lower wind noise being lower and closer to the ground.
- Unibody gives you a more luxurious ride with tire and road noise being drowned out by advancement in build quality, sound deadening and the suspension setup afforded to the monocoque chassis.
- Less squeaky components makes for less rattles and metal fatigue noises commonly associated with ladder frame chassis.
- Lighter body increases the lifespan of the tires, suspension and other wear and tear suspension components.
- They also offer better balance in emergency braking and manoeuvring situations.
Advantages of Body On Frame Chassis
- The structure is extremely rigid and robust.
- The Ladder frame is usually made to withstand various angles with weight being distributed unevenly for extended period in off road conditions.
- High torsional stress abilities makes it far more durable than a Unibody structure
- The Ladder framework carries all the weight and handles all the punishment off road.
- Unibody chassis will require some serious engineering to be able to endure the amount of punishment a ladder frame can easily withstand.
- Body On Frame vehicles have a height and sight advantage over smaller cars, allowing them to identify a potential dangerous scenario before it happens.
- Drivers of Ladder frame pickups can make life saving decision, by reacting sooner since he has a better field of view over a small car allowing him to avoid a potential collision.
Monocoque SUV A Safer Option
So does a monocoque SUV offer more protection than a ladder frame SUV and are their occupants safer in the event of a collision between the two?
Most modern SUV’s are being built with Unibody or monocoque structures for obvious safety reasons. This factor also results in a lighter, less rigid structure that is less likely to roll over than a ladder framed chassis SUV derivative.
Studies reveal that the occupants of small passenger vehicles are at a lower risk of dying when impacting an SUV with a monocoque Unibody structure. Occupants are 18% safer when impacting Unibody SUV’s over Ladder Frame SUV’s, making the Monocoque SUV safer for its own occupants as well as those of other vehicles.
Vehicle safety has improved exponentially over the last few years. Generally speaking, a modern small car packed with safety features is safer than an old traditional pickup. The more modern body on frame UTE’s and SUV’s are packed with safety features that can rival any luxury sedan. They also have physics on their side with the weight factor. The bigger the vehicle, the safer. Combine size with technology and physics and you have a winning recipe.