that is easy. as scotsman said ,streeeeetch, ouch.
imagine:
you are driving 60mpg on the road, in a gentle curve.
the inside wheels are going slower than the outside wheels ( cuz outside has farther to travel , right?)
now the spider/side gears in the front and rear axles allow this to happen , with no problems for this, what so ever (differential action, this is called and thus that name.)
ahhhhh, but the front and rear do not have this DIFF action.
so if you are on ICe, snow , or sand /dirt/gravel/etc/ all is well, but
as you come to dry pavement (or just slightly wet)
the front and rear can be going at different speeds, (the axles )
this means the front axle is now fighting the rear axles and this is called Windup.
as the old saying about chains, with the weakest link, will break first.
that is Mr. Scotsmans point, the chain takes the full force of this energy.
it really messes up that chain. ( all damage is cumulative too)
best , is if you are on ice and the road clears , is to slow way down, and bump that lever to 2wd. till you see ice again.
This all sounds inconvient ,but car cost $7k not $30k ( it's like a ww2 jeep)
all above front wheels locked of course.
some ppl drive all winter long ,with the hubs locked, it only wastes gas.
ps;
kickdata | FreeDrive.com | Online Storage and Social Utility
see owners manual top right, click it a, then click large blue down arrow.
this is not AWD car.
nor is it full time.
just measally old 4wd part time.
yours is old ,but the same , 4wd op's wise.
hope that helps you.
cheers.