Mike,
I think maybe we are familiar with or thinking about different
vehicles. While I have not looked lately cars like Subaru and Audi
with AWD only have a normal manual or automatic transmission and as
the driver you have no control of the "transfer case." But there is
a possibility of bad old age memory. On the other hand my Jeep for
instance has 2WD H, Part time 4WD H, Full time 4WD H and Full time
4WD L. In two of these options the inter-axle differential is lock
so the front and rear wheels turn at the same rate and in the other
two options the inter-axle differential is not lock allowing the
front and rear wheels to rotate at different rates. Of course in 2WD
H the front wheels receive no drive power either.
None of this is of any help to stupid drivers. :-)
Bob Kitterer
1960 Sprite (Mk IV in disguise)
1966 Sprite Mk III (Trevor, in boxes)
2000 Miata Special Edition
2002 Jeep Grand Cherokee
On Sep 18, 2005, at 12:14 PM, Michael D Myers wrote:
> 4WD generally has a transfer case with low and high range gearing for
> off-road low-speed use.
>
> AWD provides drive to all wheels but does not have the low range
> option.
>
> If you do not have a center differential between the front and rear
> driveshafts, operating on dry pavement can induce driveline windup
> since
> the front wheels need to travel different distances than the rear
> wheels
> due to turning and the Ackerman effect. On loose gravel, dirt or snow,
> the tires will slip so this is not a problem.
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