c4 front wheels dont spine in snow need help

[porsche 996 c4 dg]

first snow today tried the car in the snow 2000 996 c4 cab dsp was working good i live up a hill you need a4x4 to go up got up but seems only the dsp did the work the front wheels dont spine only back need help wath should i check the front dif is there a shaft going from front to back does not look good looks like 4x4 is not working

[wvicary]

If you made it up a snow,covered hill that you usually need a 4X4 to climb, I would think that the all-wheel drive is working.

[GTF]

Am wondering if you have winter tyres fitted?? I also have a 996 ('99) C4 that I have run in the winter with P-Zero's, and generally it's been OK except for getting on the driveway. I have a fairly sharp turn, minor incline, and have found in snow more than 6" deep that the front wheels don't move but the rear spins. Gentle rocking back and forth and much shovelling of snow is requried to get the car on the driveway.

I'm thinking about fitting snow tyres this winter as I am planning several trips to the hills for snowboarding (I'm located in Scotland). I have kind of convinced myself it's a good idea but what does the panel think?? (Apologies for high jacking this thread.)

GTF

[fastboydave]

Your '4x4' only gives something like 5-40% drive at the front (variable), therefore i would suggest that if the grip is the same at front and rear, the rears will only spin (mine does too). Only in unusual circumstances where you have low grip at front and high at rear would the front spin. The front 'drive' is not designed to run for prelonged periods of time too, as its a viscous clutch i think and will get a bit hot? Also, the tyres are narrower at the front, which in snow gives higher grip as it cuts through better.

GTF, i wouldnt bother with snow tyres, it surely will only improve it a very small percentage? Get yourself a little front wheel drive runaround (with narrow tyres), or a proper 4x4 to do that stuff. Mind, there will be many guys on here that have gone down that route who will be able to advise i guess..........

[wvicary]

I can't speak for C4's but winter tires make a huge improvement on the vehicles that I've fitted them on. I also live in central Canada where it's often -30C with loads of snow in the winter, so need less to say all Porsches are tucked away for the winter.

[porsche 996 c4 dg]

Am wondering if you have winter tyres fitted?? I also have a 996 ('99) C4 that I have run in the winter with P-Zero's, and generally it's been OK except for getting on the driveway. I have a fairly sharp turn, minor incline, and have found in snow more than 6" deep that the front wheels don't move but the rear spins. Gentle rocking back and forth and much shovelling of snow is requried to get the car on the driveway.

I'm thinking about fitting snow tyres this winter as I am planning several trips to the hills for snowboarding (I'm located in Scotland). I have kind of convinced myself it's a good idea but what does the panel think?? (Apologies for high jacking this thread.)

GTF

no hi have new summer tires was not really planing runing the car this winter but maybe in nice days was surprise to climbe the hill there was not 6inches of snow maybe 1 inche compacted slipery was wondering if your car spines or have you ever seen it spine in the front hade a audi a4 quatro and wen i flored it in the hill could see the snow lifting from front wheels sorry was not {dsp} but for porsche called the{psm}that semed to have got me up the hill was floring it on top of hill triying to make spine in front and never the front wheels turned can anybody that has a c4 tel me if they have seen the front wheels turn or spine like audi quatro thanks

[porsche 996 c4 dg]

Your '4x4' only gives something like 5-40% drive at the front (variable), therefore i would suggest that if the grip is the same at front and rear, the rears will only spin (mine does too). Only in unusual circumstances where you have low grip at front and high at rear would the front spin. The front 'drive' is not designed to run for prelonged periods of time too, as its a viscous clutch i think and will get a bit hot? Also, the tyres are narrower at the front, which in snow gives higher grip as it cuts through better.

GTF, i wouldnt bother with snow tyres, it surely will only improve it a very small percentage? Get yourself a little front wheel drive runaround (with narrow tyres), or a proper 4x4 to do that stuff. Mind, there will be many guys on here that have gone down that route who will be able to advise i guess.......i

i guess if i put the 2 back wheels in garage on floor and 2 front wheels out in snow the 2 front wheels should spine going foward that would be a way to test it by wat y understand your car would spine by the way today in montreal canada 15 to 20 cm of snow dont think would be able to go up the hill before snow plow passes so wat you are saying is that the system on c4 is not like audi quatro that wen you floor it the front wheels spine the other thing i was wondering is wen you take the psm if you have it on your car does only the back spine this summer wit my hold tires that were bad in the back on wet street with psm on car would stay like i was on rails even i would floor it trying to loose back but if y took psm of would loose back and donught right away wath about yours i dont know the truth is y thouth front wheels were supose to work more than that in snow actualy dont seem to spine at all dont think it is normal does any body have a answer that could help me convince my self that every thing is fine with my car for now i am deceived of 4x4 system on car thanks

[GTF]

As mentioned above, the C4 is not a true "4x4". I guess the Audi was??

This will be my 4th winter with the C4 and apart from the minor inconvenience of shovelling snow from the wheels on my drive, it's been fine. I haven't noticed the front slipping/spinning but have seen the old "rooster tails" from the back but the PSM kicks in and transfers the power to calm things down. The car has remained on the straight and narrow, does not squirm about and feels in control.

As long as you can drive in the snow, I don't think there is much to worry about.

[fastboydave]

Thing is porsche 996 c4 dg, if you put the rear wheels in the garage it will just simply push off and you wont tell. Its very difficult, i suppose the only way is lift the car on all four corners. I suspect everything is fine and you have nothing to worry about. Infact, wouldnt a 'dash light' illuminate telling you of an issue?? Maybe someone knows??

[wwest]

Porsche uses a VC, Viscous Clutch, to couple the front driveline into the rear. Initial coupling coefficient is only about 5% and will increase to about 40% with an extended period of disparate wheel rotation at the rear vs the front, which CANNOT happen if Trac is active.

Edited November 22, 2007 by wwest