Wheels spinning and being constrained cyclically by the VW ESP system sounds and feels rather like the axle tramp my fathers' Sunbeam Rapier H120 "suffered" from when I drove.
So a too heavy right foot in my opinion.
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So a too heavy right foot in my opinion.
I do seem to remember that my friend is rather partial to a leaden boot on the throttle pedal.
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Depends on how you define axle-tramp.
My definition is the shaking you get from a solid rear axle with no Limited Slip Diff, as one wheel grips, and the other shakes the whole axle. Plainly this type of 'axle- tramp' cannot happen to a fwd car with independent drive to each front wheel, such as a Golf.
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A front wheel drive car has the same type of differential as a rear wheel drive.
Sorry - but there is never independent drive to each wheel AFAIK.
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In the definition of axle tramp, it's the independence of the wheel location, not the independence of the drive that's important, as GWS hints above.
Axle tramp is a vibration mode of the whole axle, which, viewed from the rear looks like the axle rocking clockwise, and then anti-clockwise. The wheel which is unloaded, typically, slips for a short period, and then grips while the other side wheel slips.
As a typical live axle also reacts the torque along the direction of the propshaft, there is usually a wheel biased towards being unloaded - usually with conventioanl engine rotation, the driver's side.
As a further complication, the axle also reacts the drive torque, and so it winds up when viewed from the side, with the pinion moving higher under more drive torque - obviously, during tramp, the drive torque is constantly changing, dropping each time a wheel slips, and so, the pinion nose will tend to dance about a bit too.
The cure for this axle tramp is generally better axle location, and higher damping (you need to make sure that the energy dissipated in a hypothetical cycle of vibration is greater than that available to drive the motion).
For an absolutely classic demonstration, try an adventurous start in an unmodified Morris Minor. The vague location offered by the leaf springs, and the poor damping provided by the lever arm dampers will almost guarantee some tramp.
In short, you can't have what is classically known as axle tramp in a car where the driven wheels are independantly located, whether FWD or RWD.
Number_Cruncher
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You can't have axle tramp, no, because you have to have a rigid axle for that. But you can have wheelspin, exacerbated by the elasticity of tyres and compliance in the suspension linkage. It may feel a bit like axle tramp in the event.
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You can't have axle tramp, no, because you have to have a rigid axle for that.
Better to call it wheel hop then? Not full wheel hop where the wheel leaves the road, but enough to let the tyre slip/grip/slip/grip under some circumstances, instead of normal smooth wheelspin.
I've had this in a FWD car, I guess more than once in a Mk2 Cavalier 1.8i when I was a teenager. And perhaps in a Mk3 Golf that was softly sprung. In these cases I think it was caused by inadequate damping and me having too heavy a right foot..
Edited by Rich 9-3 on 08/01/2008 at 17:40
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Could it be that the heavy right foot is working in conjunction with a flatspotted tyre to produce a noticeable judder?
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Despite only having about 60hp my Mk1 Fiesta was easy to get the front wheels bouncing around, but it did take some heavy right foot and a quick clutch release!
I suggest the owner tempers his right foot - my DSG A3 170 diesel will spin it's front wheels, but if it does it's because I'm giving it too much gas.
Ask him how long his front tyres are lasting too.
My A3 DSG 140 fronts lasted 23,000 miles, the Audi salesman did tell me he had someone complaining that his tyres had worn out by 8,000 on the same car.
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The non sport FWD Cavaliers used to suffer from what felt like tramp, but I think later ones were ok.
But true tramp is a twisting of the axle, and when a wheel spins, this twisting is released. Older track RWD cars will often have anti ramp bars, or if you go the whole hog, upper and lower arms and a Watts linkage (panhard rod but better).
If the OPs car has got worse, first thing I'd look for would be a failed engine mount or damper Austin Maxis used to eat the dampers and with a broken one, you would get what felt like tramp. Jerks all over the place!
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I was told off for calling it axle tramp!!! I know the effect tho, wheels hopping up and down, skipping, tuggin at the steering wheel....
Nothing wrong with the car, just that your friend does not know how to handle or deliver the 170HP available at the front wheels.
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I will take onboard all that you have had to say regarding this matter and will print out this page and give it to my friend tomorrow, which will be after he has visited his supplying dealer in South London!
He did phone Milton Keynes about this 'problem' and they said that they have had some previoius complaints that may be related to a faulty operating system (a valve perhaps). We'll see.
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My mk2 Cavalier SRI would do it sometimes and it felt truly horrible. Like someone rapidly thumping the floor of the car with a big hammer.
Over exuberance (18 yrs old) was the problem. That said, it was the easiest car to wheelspin that I've ever owned. No wonder the twockers loved them.
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