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View Full Version : Quattro - is it really 4 wheel drive?



Andrew W
28-01-2007, 02:02 PM
I recently became a proud owner of an Allroad (with Quattro transmission of course). Yesterday had to avoid an obstruction by driving onto muddy verge (nearside wheels only), speed less than 10mph. Result? nearside wheels spin, offside don't move! Car stops. Great embarrassment!

I'm a new bug to both a Quatrro and this forum - advice welcome!!

Huweth
28-01-2007, 02:16 PM
I've always wanted one of those. Maybe when I change the Passat...

Has it got EDL (Electronic Differential Lock)? What about other settings for the Quattro system?

I suggest sitting in the car with the Owners manual and reading it cover to cover. Try out every button, adjustment, every whatever. That way you know your car before you get into sticky situations (like muddy verges).
I always make sure I'm fully aware of what a new car has/can do. That way I don't get myself into a situation trying to do something it can't!
Good luck, and if the Quattro has failed, you know where to come for help.

adamss24
28-01-2007, 02:56 PM
If you wanna go over ditches and stuff, get a Land Rover. Your car traction is as good as your tyres are and there is a big difference between a true off roader and a audi quattro ! For start, audi's quattro system is designed to give you better(slightly) traction in less than optimal situations, like rain watter puddles and wet leaves or a bit off snow but its still designed for tarmac !?! Besides, you should see if any off the traction control features are innactive and see the option list...Its a bit weird that your allroad was not able to go trough a bit of mud but hey, if you were looking for a true allroader, then i sugest you look elsewere...

Andrew W
28-01-2007, 04:38 PM
Hi, yes I know what you are saying. I used to drive a Range Rover classic (w/o diff lock) and it was by no means perfect in similar situations. It's just that I thought the Torsen diff was supposed to sort things out mechanically w/o the need for fancy gizmos. Just overblown hype I guess!!

Huweth
28-01-2007, 05:52 PM
I actually reckon the Allroad is superb in low traction situations.
I go skiing everyyear to Austria. Each day I see all kinds of cars with snow chains on, and they still struggle. The Allroads (and all Quattro's for that matter) don't bother with snow chains and still do better than the others. You can't fail to be impressed when a car goes from standing to 'silly speeds' up a steep hill in 6 inches of fresh snow with ice underneath!
There's also an Audi test track near where I stay where they develop their traction systems in snow and ice. Those cars really can shift on snow.
The only time I can ever imagine them coming unstuck is due to the low ground clearance. Thats when you need a Landrover!

Andrew W
28-01-2007, 06:14 PM
This is weird, unless dry snow with non-slushy ice underneath actually has more friction than our wet stuff?

Maybe it's a speed thing? (couldn't go too fast as the obstruction was a parked lorry with metal spikey bits!). Have heard that gently applying the brakes while maintaining power would have helped - but didn't remember in time - any thoughts?

Re clearance - not true actually. The underside of the Allroad is wonderfully flat, with all the bits (including exhaust) cleverly tucked away. On height level 4 it has better clearance than the landies with all their bulbous differentials drooping down. Though you can't exceed 10 mph else the smart (too smart) system drops you down to level 3.

For info - my allroad has the auto tiptronic box - not the manual with low ratio (though unsure that this should help in this situation). Also, while it was indeed a verge it did have a few inches of liquid mud where other vehicles had gone through (tho they were probably tractors). The tyres are certainly not off-road but the point being any power at all to the offside wheels would have trickled me forward.

Andy B8 - just read your posting thanks. There is no diff lock button on the allroad, just one to switch off the ESP. Everything else is supposed to be automatic. I know the ABS works fine (no warning lights also felt it cut in the other day) and that works in concert with the auto diff lock. Time to go to a dealer I guess to get it looked at in detail! Thanks guys!!

ps just in case anyone else says it - I have indeed read the manual, I may be coming over as a twonk but I'm not a complete one!! :-)

gazza57
26-02-2007, 01:24 PM
from what you have just described, I think that either you have your ESP (Electronic Stability Program) switched off or you have a fault of some description.
With ESP as soon as you entered that muddy verge, the nearside wheels which have lost traction should have the power removed and rerouted to the remaining pair of wheels on the offside which have the grip to wind you through the verge.
If your ESP is off there should be a warning beacon in the dash showing it is disabled. the lamp may be faulty but you can test that at ignition switch on when all lamps will illuminate for a short time. if it does not appear then you have a faulty lamp indicator.
Another way to check is to switch the ESP on by the button on the dash and make sure the ESP disabled lamp illuminates.
Perhaps the best way to check the whole system though is to get the system interrogated and check for fault codes.These are generated by the system when an appropriate sensor fails to respond correctly to a test signal applied by the management system. Each code signifies a particular sensor which has failed to respond correctly to a test signal applied by the management system.
For example nearside front wheel sensor faulty for example.
Gazza 57

Andrew W
03-03-2007, 03:27 PM
Thanks Gazza. The ESP lights OK - so electronic interrogation prob the only way to confirm. Though am still a tad disappointed - in the days before all these electronic bits I thought the Quattro made it's name with the Torsen diff that transferred power mechanically...

Zub
03-03-2007, 07:58 PM
I think the quattro is the same as my 4motion in my Passat and it is only part time 4wd. Not that that should have stopped it from working or course. My 4motion came in very handy when i went in snow that was a bit too deep when going snowboarding at Glenshee.

jansko
26-06-2008, 11:46 PM
quattro and 4Motion are just trademarks, they both cover torsen or haldex differential which work in a very different way.
Your passat may be torsen or haldex, depends on what year is it.
older are torsen, newer are haldex as all Golfs, Octavias are haldex.
allroads are torsen.
;)

scotty33
01-07-2008, 10:52 PM
As far as I know, the Torsen diffs are 'self locking' i.e. no electronics. But they do rely on oil between the vanes to operate correctly. And they would not 'lock up' in the true sense of the word at slow speeds. There will need to be a speed mismatch before the power is delivered to the stationary wheels, maybe you weren't spinning the loose wheels fast enough to make this happen?

Andrew W
02-07-2008, 08:01 PM
Thanks Scotty - I probably didn't spin them very fast. I'll bear that in mind if I encounter it in future (now, where's the nearest patch of mud...? ;-)

joca
02-07-2008, 10:09 PM
If you have a torsen on your car.....

Torsen stands for torque sensing and is a multiplier kind of differential which needs some torque to multiply and pass on.
If you have 0 torque and you multiply by anything result is 0 (0x5=0)
Maybe you lost all torque by getting to mud before wheels gave some torque slippage to diff.

I found this info on a site a long time ago (when i bought my quattro)

:o

ddp100
03-04-2009, 03:38 PM
A bit after the event, but I agree that it sounds like a fault or ESP off.

I've also got a TDI Allroad, because I live out in the sticks and am forever avoiding tractors and the like on single track roads where I end up on the verge! About two weeks ago I had to do exactly the same as you, except it was offside into the mud (the nearside was hedged) and the mud was several inches deep and wet. I had no problems at all getting out, on a bit of an incline (both uphil and the verge slanted away from the road) and I'm on Goodyear Wrangler F1s that are nearly at the end of their life.

Hope you got to the bottom of the problem and are now happily chugging along in your Allroad!

zollaf
04-04-2009, 02:42 PM
with two wheels on the same side in mud, the centre diff will only transfer the torque to the front and back axles, then the diff on the axle will transfer the torque to the wheels with least grip, so you end up with the wheels in the mud spinning. this is where you need a difflock in the axle. this applies to all 4x4 vehicles, even landrovers.so unless you have limited slip diffs, or a difflock, your not going anywhere, unless you have traction control, that will apply the brakes to the spinning wheels, thus pulling you out. in snow, or on grass/mud, its a different matter, as all the wheels have roughly the same limited traction, so the centre diff sends the torque to the front and back axles, and you dont have undriven wheels causing drag.