The advice to fit any two new tyres on the rear wheels arose, if I am not mistaken, in the time when all cars had rear-wheel drive, when it made sense.
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What\'s for you won\'t pass you by
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I always put new tyres on the front, on the assumption that they are more safety critical than rears. A front tyre blowout, I'd imagine, is more dangerous than a rear one in normal driving conditions in a car that is not heavily loaded.
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I think the theory is that a front wheel slide in an emergency is dead easy to control, a rear wheel slide not necessarily so. That's my understanding anyway.
www.honestjohn.co.uk/forum/post/index.htm?v=e&t=36...3
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Tha advice to fit new tyres on rear is given for fwd cars I believe on the gorunds that lift off oversteer/ rear end breakaway is more severe in a fwd car.
My experience of that is it's usually caused by driving too fast round roundabouts on motorway approach roads in the wet when there is oil on the roads.
I have switched new tyres to both fromnt and rear (in pairs of course) and have to say I cannot notice any difference at all. My rear tyres have 5mm tread so I would not expect much..
The people I see driving too fast round corners in the wet in fwd cars - often at maniacal speeds - suggest to me they neither know nor care about such advice...
madf
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The advice to fit any two new tyres on the rear wheels arose, if I am not mistaken, in the time when all cars had rear-wheel drive, when it made sense.
Well the CURRENT ADVICE by at least two major tyre makers, as I have previously posted, is put new tyres on the back irrespective of FWD or RWD.
I accept what they recommend but you have the choice.
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Still got a little over 5 mm.
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Actually it is a rear wheel blowout that would cause you more problems than a front wheel blowout.
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I have 2 x FWD cars and Costco always puts the new tyres on the back.
Reason?
On a FWD car the front tyres wear much more rapidly.
The rear tyres show little or no wear @ say 25,000 mls (2-3 yrs in my case) and to all intents are like new Treadwise 5/6mm at least
If they leave them on the back they might start to crack with age - the original tyres still might have could be 7/8 yrs old and have 75,000 mls on them.
By always putting new on the back - the front the tyres will be a maximum of 4/5 yrs old and should not suffer cracking due to age / sun etc.
Problem
Garages take off wheels @ service time and they do not always put them back in the same axle.
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My little AX had a blowout on the rear and it lifted the front opposite wheel, very difficult to control and if I wasn't on a dual carriageway could have resulted in an head on.
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The only blowout I have ever experienced was the offside rear in a VW 411, on a dual carriageway at 80 - 85mph. Apart from the bang, no drama whatsoever. The car tracked straight and could be driven onto the verge for a wheel change.
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On the front. I assume the rears are 50% worn or better, then on the front no doubt. Regards Peter
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I'd put them on the front too. Once they're scrubbed in, new tyres will give better braking performance especially in the wet. This falls off quite considerably well before the tyres become too worn to be legal. Something to do with the 'sipes' (small cuts in the tread) which aid with wet grip but don't always go all the way down the tread.
I would think lift-off oversteer in fwd cars is seldom experienced by most drivers. It's more affected by worn dampers than worn tyres. Of course press-on drivers sometimes induce it on purpose, grinning from ear to ear.
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I had a chat with the local mechanic, and while he admits that putting new tyres on the back is the traditional way on a FWD car, he now doesn't because modern tyres/cars apparently develop a wearing pattern based on where the tyre is in relation to the car. It is slightly different when they are on the front/back. Thus he now puts new one's on where they are required, rather than move worn one's to the front, as this is supposedly safer...
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On the front (with FWD). It just seems sensible to me to have the tyres with most tread where they will suffer the most wear.
Maybe the advice from tyre fitting firms is something to do with avoiding liability?
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I put new tyres on the front.
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FWD the new tyres should go on the rear.
Reason is that the new tread block distort easier than the used tread blocks. If the new tyres are fitted to the front the rear will have far more grip that the fronts leading to terminal understeer.
If the rear of a car steps out you can correct the oversteer by steering into it, if the front breaks away you have no steering and you go straight on, if you brake you also go straight on.
I remember this being demonstrated on the old "Driven" C4 program.
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2 Dirty VW diesels and a Honda with an 18 inch blade
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Dox, what you say is true for dry road cornering, where most drivers are nearly always well within grip limits anyway, not wet road braking where they often aren't. At the speeds most people (quite rightly) drive at, understeer may be technically present in cornering but won't be noticeable.
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Dox, what you say is true for dry road cornering, where most drivers are nearly always well within grip limits anyway, not wet road braking where they often aren't. At the speeds most people (quite rightly) drive at, understeer may be technically present in cornering but won't be noticeable.
Don't know whether you've noticed but its quite dry at the moment ;-)
His current rears have 5mm and will deal with water well.
Its recommended that FWD or RWD new tyres are fitted to the rear for the reasons mentioned.
Ask your tyre dealer for advice and see what he says.
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2 Dirty VW diesels and a Honda with an 18 inch blade
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Dox, I regret to say you are completely wrong. The reasoning is that the new tyres go on the rear to prevent oversteer that might arise even on a FWD car if the fronts have much better grip than the rears. Understeer is generally much safer than oversteer which is why almost all cars are set up that way, and fwd cars are considered safer for normal use by drivers untrained in skid control.
That said I prefer to put the new tyres on where they wear fastest, i.e. on the front.
I suspect this advice is related to supposed potential liability for tyre fitters. It only seems to have become an issue in the last couple of years, prior to that they would put the tyres on where you wanted, now many insist that a pair of new ones goes on the back.
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As far as I know, all the tyre manufacturers and the likes of Micheldever Tyre Services recommend putting the deepest tread on the back, irrespective of FWD or RWD. I trust them.
For example:
www.michelin.co.uk/uk/auto/auto_cons_bib_pqr_neuf....p
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Thanks to everyone for their responses, I'm surprised by how many have come back.
Given that the rears have something like 5.5 mm left anyway, I'm going to leave them on the back for now. I'm doing 35k a year, so age is not going to be a problem, and they have plenty of tread to avoid chronic problems. Anyway, I've got a stability program on the car (which has only activated once, when I deliberately provoked it on a deserted wet roundabout).
All in all, I think I'll have a go at eliminating the (mild) tramlining by fitting them to the front. Cheers for all the feedback. Hopefully this decision won't lead to my oversteering off the road in the alps in a couple of weeks :-).
Gord.
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good decision gordon.
it is always worth remembering this vital note:
www.honestjohn.co.uk/forum/post/index.htm?f=4&t=33...1
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Well exactly! :-)
Now I just need to decide whether to start doubling up the oil changes, but that's another thread in itself...
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I note the argument about blowouts of rear tyres leading to loss of control.
I have to say my experience is the opposite.
I have had two blowouts : both at speed >60 mph and both on the rear wheels of rwd cars. In both cases I was able to stop in safety with no noticeable loss of control.
These may be isolated instances of course.
madf
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I agree with madf (see earlier post above) on rear blowouts. Perhaps if it occurs when one is cornering hard the story might be different.
I note, on the subject of which end of the car to put new tyres, that Bridgestone disagrees with the other tyre makers at least where front-drive cars are concerned. Since there can't be any crucial difference in the actual tyres, clearly 'industry wisdom' on this matter is marginal at best and probably a matter of opinion. I just don't buy what they say about 'straight-line braking' in the wet. If the brakes are working properly you want the good tyres on the front. However if only one front brake is working then the car might start to rotate. But you would have noticed the condition and done something about it, wouldn't you?
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Manatee. Why do you think new tryes have better grip than half worn rears may have. The new tyres no not reach best performance for a 1000 miles and rears are spot on as they are The front is where ( wear ) (excuse the punn ) the new tyres need to go this time of the year and with half or less worn rears. Winter may be diffeerent, infact the car the age the tread pattern, all of these effect how best to fit nesw tryes but with a well loaded car and the OP usage the front is where they should me. Regards Peter
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I absolutely agree as to where I would put the new tyres, I'm just stating the logic behind the now almost standard industry advice on fitting new tyres to the rear. In the dry part worn rears should be on a par with new (better probably for the first few miles until the release compound has worn off) but in the wet, when overall grip is more likely to be lost, deeper tread shifts more water doesn't it?
It's also generally reckoned that blowouts are more dangerous on the back than the front (not intuitively obvious, but it is apparently so - negative roll radius steering on modern cars helps, and steering input is available to help correct the consequences of a front blowout) and newer tyres should be less puncture prone.
That said, again I would personally put the new on the front, as I choose to drive well within the limits of the car and prefer to have maximum tread on the front as winter approaches (odd comment when the temperature is 29C).
I'm not trying to win an argument btw, and am happy to be pointed to further information.
Strange how practice on this has changed, and very irritating when you can't make a tyre fitter do what you want!
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p.s. -
The Michelin link posted above by Roger seems to rely on theory that new tyres have more grip, and that understerr is safer than oversteer for "inexperienced" drivers - for that you could also read surprised drivers. Caught unawares by understeer, most people's instincts would be to back off and increase steering lock - which just happens to be the right response. Without practice or instruction, few drivers can reliably correct an abrupt rear end breakaway even if they are qick with the opposite lock.
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Caught unawares by understeer, most people's instincts would be to back off and increase steering lock - which just happens to be the right response.
Sorry if I'm misinterpreting you, but increasing steering lock during understeer makes matters worse.
I went on a skid pan training course where we we told to back off the power then straighten up - i.e. steer towards the solid object you're about to hit - then turn in again gently. This is not a natural reaction and one I'm not sure I'd be able to repeat in the wild. Having tried it in the controlled environment of a skid pan (and in someone else's car) I can say it does work.
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Trevor H, good point - if the fronts have lost all adhesion (thinking usually ice/snow or aquaplaning) then throwing more lock at it isn't going to help! Like you I have been able to play at this on a skid pan, but I have only once, as a feckless youth, encountered it on the road and I won't go into the outcome, except to say it involved a lot of snow and a lamp post. I think most drivers, most of the time, would come to grief with this situation unless they had plenty of room - good driving is not getting into it the first place.
I was thinking of the much more commonly experienced initial understeer brought on by a bit too much speed and throttle, (thinking greasy roundabouts) when the front starts to run wide, rather than the full "straight-ons". Most people, experienced or not, will instinctively back off, regaining grip, and then turn gently back on course - the extra grip demanded being more than offset by the reduction in speed. Maybe it's not skid pan technique, but if it didn't usually serve then there would be inattentive drivers shooting off at tangents all over the place.
It's certainly the case that fwd is regarded as much safer for inexperienced drivers and I don't think that depends on them all having the presence of mind to straighten up every time a bit of understeer creeps in, but I think you were right to correct my rather sloppy summary!
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It's the old story: tell me what kind of an accident you're going to have, and I'll design the best system to mitigate its effects.
1. Most vehicles (before the ABS cuts in) have between 2 and 4 times the braking effort on the front wheels.
2. Aquaplaning renders the vehicle unsteerable and largely unbrakable.
3. Tyre blowouts are related to age of the tyre and to abuse, eg. kerbing sidewalls.
Let's assume that a vehicle is being driven sensibly within its limits and that an accident is likely to be the result of some unforeseen action by others or by nature. This could be a child running out in front of vehicle on a wet road, a flash flood on a motorway or a random tyre failure. In all of these instances, better tyres on the front will yield a safer outcome.
If a vehicle is not driven safely within its limits, more grip at the back may delay the onset of terminal oversteer.
Newer tyres on the front for me every time.
659.
ps. I learnt a long time ago never to allow a tyre fitter anywhere near a vehicle unless you want a dented floor and overtightened wheel fixings. I always take loose wheels to a tyre shop - this also neatly overcomes any difficulties as to which axle the wheels end up on.
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As I thought, this will go on for a while as always. Regards Peter
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A follow-up. Fitting guy turned up and put the tyres on. No problems, although the fit was pretty tight and took him a while on one of them. They're on the front.
Was quite pleased tho - he came up with a no-cost solution to my spare tyre problem. Can of gunk is okay(ish) while in this country, but I was twitchy about two weeks in France without a spare and was going to spend £100 on a spacesaver. Fitter suggested that as they was space under the boot for one of the tyres coming off, which is in good condition with 2.5 mm or so of tread left, I should take the carcas with me. As he points out, finding a fitter should be easy, finding a tyre much less so.
It's not a spare, but it does mean that pretty much any rescue outfit should be able to get me back on the road if needs be. And it can just go in the garage here when not needed.
All in all, quite pleased with Black Circles once more.
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