I don't, really.
Anyway, girlfriend went to a festival last weekend, they have 18 hours of rain the first day, about 12 hours of rain the second day, she ended up driving out over the equivalent of a large, saturated, ploughed field.
Car has now got a vibration in the steering wheel that is noticable above 70mph. I wondered if anyone could work out what is causing it:
So yeah, steering wheel rapidly judders left and right, and then doesn't, and then does, and then doesn't. It's governed by a low-frequency oscillation, a sine wave-ish pattern - the juddery movement fades in and fades out, over a wave that takes approx. 8 seconds to complete at 75mph. 4 seconds of shaking, 4 seconds of nothing.
So I suppose my question is: What car part, that has some effect on the feedback to the steering wheel, cycles at wavelengths that long (around 8 seconds) at 75mph? I can't imagine anything taking that long to cycle at that speed.
Thanks, nerdy anorak types.