Traction control system (TCS) in general, is better than a limited-slip differential. It has more pros than cons. Several notable heavy-duty off road vehicles, like the Hummer H1, Land-Rover Range Rover and Toyota Land Cruiser use it.
The 2008-onward Toyota Land Cruiser uses nothing but traction control. It has a limited–slip center differential that can be locked, but the front and rear differentials are open.
How effective traction control is depends on how well its programmed and what vehicle its going to be used in. A car, crossover SUV or minivan’s traction control system is not going to be programmed for off road use like a traditional SUV or pickup truck.
The 2007-onward Ford Expedition’s traction control system is programmed for both on & off road use.
Ford Expedition 4x2 only gets 2-wheel electronic traction control. Ford Expedition 4x4 gets 4-wheel electronic traction control.
1: It reduces drivetrain stress.
2: Driver control is not affected.
3: Less mechanical complexity means improved durability.
4: It can react faster than a mechanical limited-slip differential.
5: It will never lose its effectiveness over the life of the vehicle.
Some limited-slip differentials will lose their ability to transfer torque
as the internal slip inhibiting device (usually a clutch type system) becomes
worn from use over time. Eventually they will revert back to an open differential,
and the internal slip inhibiting device must be repaired or replaced.
With traction control, you don’t have to worry about it losing its effectiveness, since it relies on the vehicle’s ABS brakes (something you as an owner & driver must keep properly maintained anyway).
Traction control is bundled with the AdvanceTrac electronic mitigation suite. AdvanceTrac is the umbrella name that includes the traction control system (TCS), electronic stability control (ESC), roll stability control (RSC) and trailer sway control (TSC)
Each system performs a different task. Sometimes traction control is confused with the electronic stability control system. They are not the same, and electronic stability control (ESC) and roll stability control (RSC) can actually be disabled so they do not interfere with the traction control system while it does its job to keep the vehicle moving off road.
The traction control system itself uses two ways to maintain traction at the drive wheels. Engine power reduction (Engine traction control) and initiating an ABS brake apply and release cycle (Brake traction control) on any of the 4-wheels.
Engine traction control, electronic stability control and roll stability control can all be deactivated. Brake traction control will still continue to work.
How does it compare in performance to a mechanical limited-slip differential?
If you figure the Expedition has only a rear LSD, its only going to be able to help keep traction at the rear drive wheels. The front drive wheels (on 4x4 models) have no way to maintain traction since the front axle has a open front differential.
4-wheel electronic traction control (on 4x4 models) guards all four wheels. So the rear and front drive wheels can maintain traction. It performs like having both rear and front limited-slip differentials.
Thanks guys, I appreciate the response. I'm familiar with the rears in some of my other cars, detroit locker, TL, ZF, Quaife, etc, just wasn't sure what the real story was on the new Expeditions, sounds like I have nothing to worry about.
Sure wish I knew what was in store for the 2011s motor wise, not sure whether to buy an 2010, or wait to see if the big motor is available in '11.
Considering the "push" for more fuel efficient vehicles and move away from land yachts, I doubt we'll ever see anything much bigger than the current 5.4L in our Expys...just no real market for an Expy that will tow a house.