snow story...very puzzling

[Phast SVX]

Well i dont usually go out and do stupid things in the snow, but in the parking lot wiht some fresh snow i decided to test out the AWD...Its very odd, under normal acceleration my friend (was watching from outside the car) he said the front wheels were kicking upa good amount of snow, but if i go into powermode downshifting to 1st, he said there was NO spin from the front tires, and infact my back end whips around if i turn the wheel as if its a truely rear wheel drive car, i did 2 full circles. Very odd, and im planning on video taping it to see what is up. I thought that the highest split capable by our car was 50/50...maybe its just becuase the front diff is more sensetive to spin, anyways if anyone has any ideas id appreicate it. Not that its important, curiosity killed the cat.

[Chris]

I am not 100 percent positive, but I think the split is up to 80/20. When you hit powermode the TCU has a tendency to put the majority of power to the rear for the sports car like feel. This can be seroiusly seen by a photo of my car durring launch at the race track. I will scan it and post it, once I find my HP 6300 series scanner CD. Hewlett Packard seems to have chosen NOT to post the drivers online and want your credit card number for a replacement CD. I called and asked why I could not just download them and they said it would take to long. I infomed them that with a T1, nothing takes THAT long, but they insisted that I had to pay for a replacement CD. On that note, anyone got a HP 6300 CD they can burn for me? :)
Back on track now. The center differential does not use a traditional vicious coupling unit, but instead another clutch pack similar to the ones used by the auto tranny itself. There is a duty solonid that controls hydrualic pressure to this pack forcing power to the rear, or lowering pressure allowing it to stay up front. This is what I know of the system and I think it uses the ABS wheel speed sensors to detect the slippage. On the other hand I think WOT and powermode will override any programing and forces the power to the rear for that sporty like take off. I will ask a technician for sure. Is Eddycat2000 on here yet? I think he knows for sure. :)

[eddycat2000]

Back on track now. The center differential does not use a traditional vicious coupling unit, but instead another clutch pack similar to the ones used by the auto tranny itself. There is a duty solonid that controls hydrualic pressure to this pack forcing power to the rear, or lowering pressure allowing it to stay up front. This is what I know of the system and I think it uses the ABS wheel speed sensors to detect the slippage. On the other hand I think WOT and powermode will override any programing and forces the power to the rear for that sporty like take off. I will ask a technician for sure. Is Eddycat2000 on here yet? I think he knows for sure. :)

[/B][/QUOTE]

Well, I'll try a post here. The ABS sensors have nothing to do with the transmission operation. If you've ever seen one of these transmissions apart you can tell that the front diff cannot be disabled, (unless it's broken). There is no center diff, it's called a transfer clutch assy.

I tried to make a drawing and it came out terrible, so here it is in my (probably poor) best description.

Power is inputted at the torque convertor. Inside of the extension housing there is a set of reduction gears. Those gears redirect power to the front diff. So, you will always have 100% of the drive train power to the front diff. What varies is the transfer clutch pack that is located on the top reduction gear. A solenoid activates line pressure as needed, determined by the TCU and the speed sensors to lock the rear output at certain ratios of RWD. You will *never* only have RWD unless you have a messed up transmission.

BTW- power mode only changes the shift points in the trans, it does not effect AWD perfomance. Neither does the manual button on your shifter, that just forces the trans to start in a higher gear for less wheel spin on take off.

I hope this was clear, and that it helps resolve the question.

[joeaux]

Good eddy. That's how I understand it to work. Good explaination.
-joe-

[Aredubjay]

Excellent explanation, eddy. And you claim not to have "explanitory skills." Wrong you are. Even my feeble, bourbon soaked, drug riddled, sex starved, rock 'n' roll blasted brain could comprehend. Thanks.