Axle twisters, or cross axle situations are exactly why big articulation is important in a good off road vehicle. Now, aside from a very few vehicles off road vehicles are getting less and less articulation and as a result wheels come off the ground and traction is lost. This is typically being solved with traction control which works really well most of the time, or traditionally with differential locks but are they the only means to get through them?
4Xoverland covers the technique to these situations without the aid of traction control or lockers.
And here I am me showing you how NOT to do it.
The technique is simple enough: Be aware of where your wheels are and try to keep 3 on the ground and with some weight applied to them if you can. There are going to be times when “as fast as necessary” will apply but try to stick to “as slow as possible” first.
The Idea of the 4XOverland “push pull” technique is simple - A spinning wheel has less grip than a static one. That may sounds stupid and obvious but it isn’t. Traction is a 2 part function:
- Weight on the tire (and to the ground)
- The frictional coefficient of the tire and ground
Since you can’t affect what the ground is made of and its stickiness you should focus on keeping weight on the tire; the more the better. That being said, you can affect the coefficient of friction in the sense that static friction is always higher than slipping friction; specifically, if a tire isn’t spinning it can apply more torque to the surface with a given weight than a tire that is spinning. Think of it like walking carefully up an icy slope, as long as you keep your footing you can make it, but the instant you slip you’re likely going all the way down, not just that little bit. Keeping wheels on the ground then is job 1, and job 2 is keeping the wheels from breaking the delicate bond of friction.
The challenge is to make the hill or ditch WITHOUT traction aids, because doing so gives you more options as a driver and reduces wear and tear on the vehicle. The fact of the matter is that these systems can go wrong, brakes could overheat, or be too wet to function or the system may fail with regards to traction control system, or your air or electric locker may fail to engage for some reason.
And so even in an age of high levels of computer assistance, or maybe because of it, learning proper technique still has a place for the off roader who wants to up his game and be prepared for any situation.