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Discussion Starter #1
A bit of background:

The pilot seems to have a very sophisticated electronically controlled (EC) awd system and doesn't use a typical transfer case between the front and rear driveshafts. In awd or 4wd systems that use open differentials, if, say, the right front or right rear wheels were on ice, the opposite wheel (left front or left rear respectively) would theoretically get a torque reduction or may not recieve any torque at all if the opposite wheels were slipping or totally spinning (zero traction). This is what typically occurs in a simple system with "open" differentials. To overcome this, manufacturers sometimes offer/add a limited slip diff. with clutches on the rear diff or offer locking differentials (hummer...etc). My understanding is that by switching on the VTM-4 "lock" switch, you're locking the rear diff., theoretically providing torque to both the slipping and "non-slipping" wheel, so you have power where power is needed (i.e. the surface with better traction). My question is , what's going on when we "don't engage the VTM-4...say while driving at 20-30 mph on slippery surfaces? I know the torque is supposed to shift to both front and back..but what about left/right? or does the pilot also have limited slip clutches on both front/back diff's to allow both side's of the vehicle to get torque. Also , what's going on with the front diff . under normal slipping conditions? Why doesn't it have a differential lock?

This is somewhat of a complicated question...and requires a more than average understanding of 4wd/awd systems..but i'm hoping some of you out there may have some thoughts.

2003 sandstone pilot.:1:
 

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If I remember this correctly what happens is the Pilot automatically manages the system similar to what happens when you gun it off the line. Try spinning the front wheels from a dead stop, there is no way a 240hp engine should not be able to spin them. What happens is the Pilot automatically sends up to 50% of the power to the rear wheels as you tromp it. I believe it does the same thing at other speeds as well. Your spinning tire(s) are given less power and it is balance to the other tires. I guess you could have fun with it driving on a frozen pond! I'm sure someone here can find us the full technical breakdown under exact conditions.
 

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Discussion Starter #3
Thanks for your reply. What i'm more wondering is, what happens to the wheels on the opposite side of the axle ..say with the right front is spinning, is there something in the front differential that reduces that and transmits power to the opposite front left wheel? Some cars us the abs system to break the spinning wheel and divert some torque to the opposite wheel. This "right/left" seems insignificant compared to "front/rear" torque distribution, but it can, in certain situations leave you stuck in the mud (i.e with open differentials).

Here are two great links to better understand what i'm trying to find out about the pilot's system:

1.http://www.howstuffworks.com/differential5.htm
2.http://www.howstuffworks.com/four-wheel-drive4.htm

The second link provides and outstanding animation of what happens when the "right" or "left" side of your car drives over ice...not the torque on the opposite side goes down dramatically.
 

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There was a thread way back with a link to some engineering specs and press only material. I didn't save the link. Perhaps someone else did.

My guess: Since the front doesn't have a solid axle and is able to do a 38' u-turn, the front has its own management of left/right torque split. The rear has a computer controlled electronic clutch for each side. I think the computer would be able to split the available torque from 0 to 50% for each wheel.
 

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Front diff is open.
Rear is not realy a diff, just a hypiloid gear set and two clutches to independatntly engage eash side.
 
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