Image Automatic moment distribution - what's wrong with this phrase?

For some reason, many believe that an all-wheel drive car is one that constantly turns all wheels, clinging to the road. Therefore, he allegedly is not afraid of hanging, slipping and other troubles, because of which the “ordinary” car can get stuck “out of the blue”. But this is, to put it mildly, a little bit wrong. Or rather, not at all.

If you do not take into account friction and other losses, then one thing is certain: the moment on the posted wheel of an all-wheel drive car is always zero. Regardless of the availability of couplings, differentials, dispensers, etc. When, for example, in an all-wheel drive Niva, one wheel freezes in the air, then it will not budge (unless, of course, the center differential is locked). To go, you need to block this differential. True, on an axis with a frozen wheel, the moment will still remain zero, but on the other axis, each wheel will have half the motor effort.

It is important to understand that even if instead of an axis with a locked differential, you imagine a pair of wheels borrowed from a railway carriage, then when one of the wheels hangs, the moment on it immediately disappears, but on the other it remains, although the design is clearly monolithic! But there is nothing surprising in this. You only need to understand that the half that polishes the asphalt wears out while the second remains in its original state, since it hangs in the air, although it rotates. The same thing happens on an axle with a locked differential.

Have questions? Ask! [email protected]

  • All-wheel drive ratings are available here.