Tyres..
Or more specifically blow outs. Some years ago I was overtaken by a Ford Mondeo on the M1 which had gained perhaps 50 metres on me when the front offside tyre literally disintegrated. The unfortunate repmobile slewed crazily across my path, rolling once and ended up right side up and half of the hard shoulder heading up the embankment. I wasn't hit and the driver of the other car wasn't too badly hurt. What scared me and has affected me since is that the three remaining tyres on the mondy were a good brand, in excellent condition. There had been no warning of the imminent failure and the whole event must have lasted 20 seconds from start to finish.

Since then, I have been pretty fearful of such an event happening to me despite my repeated searches on the interweb showing me the chances are vanishingly small. No waiting until I'm down to my last 1.6mm of tread for me- tyres are replaced as a set when they make it down to about 3mm at any point on any tyre. Furthermore my Focus turbo diesel (maximum speed 110mph on a good day) sits on Z rated Bridgestone Potenzas (it is probably just as well that no zz rated tyre exists at this wheel size or I'd be after those) which might politely be described as overkill and rudely described as utterly fucking pointless. Nonetheless, the tyres are rated to a much higher speed than the car can achieve which in my phobic mind equates to a greater safety margin. I will also conduct a walk 'round like a pre-flight check for any journey in any car before driving away. I have once rejected a hire care because the tyres (although legal) were below the level I would have on my own car.

I have no idea what it might take to stop me being quite so concerned about this but I guess whilst I can afford it, it comes under the heading of idiosyncratic rather than unhealthy.

I fucking hate chimpanzees as well.
(Leonard Hatred briefly did some work on, Mon 14 Apr 2008, 13:06, 7 replies)

I've had this happen to me
on a motorcycle of all things. Luckily it was the rear tyre that went, not the front - but was still bloody scary as I was heading towards the rear end of a stationary lorry at the time, I heard a 'pop' and the back of the bike suddenly started weaving from side to side. I managed to come to a halt just inches from going under a lorry. If I'd have panicked and hit the rear brake I'd probably have been dead.

Since then I've always been anal about my tyres - I carry a spare tyre, inner tube, and set of tyre levers with me, and if I ever see the slightest bit of damage the tyre gets replaced immediately.
(Half of Stephen Fry's right buttock pissed on your dog on, Mon 14 Apr 2008, 13:11, closed)

In a similar vein
I was a passenger in a Mini a few years ago when the driver's side front wheel literally sheared off. Fortunately we were only doing about 10 mph at the time, as we were driving around a very sharp bend. Had we been on the motorway doing 70 I probably wouldn't be here now...
( Davros' Granddad a voice of calm reason in a world of spastics., Mon 14 Apr 2008, 13:17, closed)

^
M4, in a Marina/Ital

One of the two hideous lumps of British Leyland junk anyway.

(I was a passenger. Times may have been hard, but never THAT hard)

Front wheel bearing lets go completely, hence wheel no longer attached to the car in any meaningful way. Luckily we were in lane 1 and the driver, as you would expect of a skydiving instructor, had quick reflexes...
(osok Rebel without a clue, Mon 14 Apr 2008, 13:24, closed)

Please stop
before you force me to go and see if the wheel bearing and assemblies of the ST170 (which are beefed up) are able to fit my car :(.
(Leonard Hatred briefly did some work on, Mon 14 Apr 2008, 13:31, closed)

This sort-of happened to me, too..
I was pootling up the M11, doing about 80mph in a Ford Fiesta van. I was overtaking a Range Rover when I saw something in the road ahead of me, poking out from the central reservation. There was nothing to do other than drive over it, and unfortunately it dented the wheel so badly that the tyre instantly gave in. The car span out and hit the central reservation, knocking the boot door open, then rebounded back across all the other lanes and ended up on the hard shoulder.

Naturally it all happened in slow motion, so the image of a truck heading straight towards me as I span helplessly towards it is ingrained in my memory forever, and gave me nightmares for a while. Luckily it missed me, but it must've been a close one.
( spatuluk, Mon 14 Apr 2008, 14:06, closed)

ST170 wheel whatnots
Just get an ST170. It rules. Also, it's so astonishingly thirsty that you won't be able to afford to drive it anywhere. Thus no risk of the tyres bursting. QED.
(theweapon never ever bloody anything ever, Tue 15 Apr 2008, 0:21, closed)

pressures
tyre pressures play a large part in blowouts, rather than actual tread left.
if you run tyres at a lower pressure than they should be they run hotter, whilst up to a point this can be good, the lower pressure causing a larger contact patch at a higher temperature producing more grip) on extended high speed runs (for example motorways) the heat can build to such an extent that it weakens the tyre (especially the sidewall) which can then blow out under the pressure within the tyre. so you needent panick too much about tread depth.
the other thing to do is have a car with low profile tyres and not a great deal of suspension movement but high quality suspension, was passenger in an r2500 cosworth back in the late 80s when we had a blow out of a rear at about 100/110 it just gave a slight wiggle and wanted to pull left slightly.
(pogo_it, Tue 15 Apr 2008, 16:17, closed)