Wednesday, March 21, 2012
What is Roll Stability Control and how does it help you? Helping to maintain vehicle control — to avoid accidents — is why traction control and electronic stability control systems are important. It’s about maintaining traction and control of vehicle regardless of road or traffic conditions. Truck owners have long opted for limited-slip and locking
differentials to help them “get a grip” in less-than-ideal driving conditions. They want more traction than a regular open differential can offer. However F-Series Pickups offer more technologies than ever to enhance traction performance. Understanding these different systems — and being able to decide which one is best for you is important, especially if you use your truck for work. Traction is defined as adhesive friction. In general, it refers to the maximum friction that can be produced between two surfaces without slipping. Most vehicles on the road today come with a non-limited-slip or “open” differential as standard equipment. An open differential lacks the ability to manage the torque between the two sides of the drive axle. With an open differential,
the torque flows to the path of least resistance. Unlike open differentials, limited-slip differentials have the ability to manage torque between the two sides of the drive axle. When a wheel on one side of a limited-slip differential begins to slip, clutches, gears or
other friction elements within the differential engage and start to transfer some of
the torque from the slipping wheel to the non-slipping wheel. Locking differentials, as the name implies, lock the two sides of the drive axle together with a mechanical connection. They can provide up to 100 percent of available axle input torque to the
wheel that needs it most. Some locking differentials require that the wheels slip a certain amount before the mechanism engages. The electronic-locking rear differential
is activated by the driver using a control switch inside the vehicle; with the flip of a switch, a heavy-duty, dog-clutch gear locks the two sides of the drive axle together to ensure maximum power to both rear wheels.
You may have heard the term, TORSEN, it's a combination of the words “torque” and “sensing,” manufactures a differential that functions as an open differential when both wheels experience the same traction and a limited-slip differential when one wheel loses traction.
Here’s how it works: First when one wheel begins to lose traction, the TORSEN differential will bind its gears together and supply additional torque to the wheel that retained its traction. TORSEN differentials transfer power almost seamlessly, and respond faster than viscous coupling to help minimize slippage significantly; which can be vitally important in the wet pacific northwest. The nature of its operation allows it to engage automatically and then return the power distribution to its rightful place once traction is completely restored. The torque bias ratio determines how much power can
be transferred. A 2.5:1 bias ratio, therefore, is capable of applying up to two and a half times more torque to the wheel with traction. This system works on-road and off, and will activate and remain engaged at almost any speed and is standard and only available on F-150 SVT Raptor.
Ford equips every F-150 and SRW Super Duty® model with AdvanceTrac with RSC. In order to have AdvanceTrac with RSC, the truck must have speed sensors at each wheel along with the ability to apply the brake at any individual wheel. This gives F-Series Pickups the capability to apply brake traction control (also known as all-speed traction control) to any wheel when slip occurs. This means added traction performance regardless of which differential (open, limited-slip or locking) the vehicle is equipped with. So you may be asking , how does AdvanceTrac with RSC improve the capability of each differential in the Ford product line? Since open differentials by themselves provide no capability to manage torque between the drive wheels, you will notice a significant improvement in traction performance when AdvanceTrac with RSC is included. As soon as wheel slip reaches optimum adhesion, the system reacts by
matching engine power (holding back the throttle, fuel and spark) and applying the brake to the individual slipping wheel as needed. Never knew your truck was doing so much thinking, huh? By preventing the slipping wheel from taking power away from the other drive wheel, the system can send as much as 50 percent of the available engine
torque to the non-slipping wheel. Good performance also achieved when accelerating from a stop on level pavement that is wet or snow covered. However it is not well suited for off-road use in base ISC mode. In deeper snow, mud or sand, you may experience a reduction in forward momentum as engine power is reduced, possibly resulting in getting stuck. Traction control Off or Sport Mode is recommended.
To ask more questions or to schedule your own test drive call 503.665.0101.