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I've come around to the idea of new tyres on the back, imagine if youre braking in the wet then all the weight transfers to the front. Aquaplaning is a function of pressure (i.e. weight) so makes more sense to have tyres that resist it most on the wheels that would be prone to it (rear).
You will also have a much longer time with low tread depth on the rear as the wear period is stretched out.
Mathematics fail.
If a tyre wears out twice as fast and is replaced twice as often it only spends half as much time 'worn out' per tyre, but twice as often.
Some weird answers on here!
If you've ever raced a FWD car on track in the wet especially, you'll realise why rear tyres are so important. Passive rear steer (accentuated with low tread on rear tyres) will mean that the rear of the car will let go pretty quickly if you do something like lifting off the throttle abruptly mid corner. There's not much weight over the rear of a front wheel drive car, so there's not much pushing the tyres in to the ground.
Contrary to what you might think from TV shows and car magazines, catching the oversteer in the limited amount of space you have on a public road is pretty hard.
Worn tyres on the front will promote understeer, which is much easier for most people to deal with - easing off the power gently will usually bring the front back in line.
JP
E.g. wet weather, you go into a corner, realise you’re going too fast, and lift off the accelerator/dab the brakes = spin. Having the best tyres on the front exacerbates this.
Anyone stupid enough to dab their brakes in a corner should expect that to happen. Having the optimum tyre set up isn’t going to solve stupidity.
Mathematics fail.
If a tyre wears out twice as fast and is replaced twice as often it only spends half as much time ‘worn out’ per tyre, but twice as often.
What the 'ell are you on about?
If you keep old tyres on the rear, then assuming it is 4 fronts to 1 set of rears you get:
End of 1st fronts - Rear 1/4 worn
End of 2nd fronts - Rear 1/2 worn
End of 3rd fronts - Rear 3/4 worn
End of 4th fronts - rear fully worn
Your rears have then been below half tread for 2 lots of front tyres.
If you swap tyres then for 4 sets of fronts you get:
End of first fronts - Rear 1/4 worn
End of 2nd fronts - New rears slightly less then 1/4 worn (as rears with 1/4 wear moved to front)
End of 3rd fronts - New rears less than 1/4 worn (as rears with less than 1/4 wear moved to front)
End of 4th fronts - New rears less than 1/4 worn (as rears with less than 1/4 wear moved to front)
You never drive with rears more than 1/4 worn
Net result is by just changing the fronts your rears are more worn (than when rotating) for the time it takes to wear out 3 sets of front tyres longer than when rotating as their wear period is longer and thus extended.
and to put it another way - at the start of each new pair of tyres being fitted:
No rotation:
New fronts : New rears
New fronts : 1/4 worn rears
New fronts : 1/2 worn rears
New fronts : 3/4 worn rears
New fronts : Fully worn our rears - shit, 4 new tyres time as my rears are knackered.
With rotation:
New fronts : New rears
Slightly worn fronts : new rears
Slightly worn fronts (but less than above) : new rears
Slightly worn fronts (as above) : new rears
and so on...never need to fork our for 4 tyres and never have rears below 1/4 worn (ie over 3/4 tread left)
@johndoh
So you've never, even once, found yourself going a little too fast into a corner with an unexpected tightening radius and had to lift off? You must be a driving god.
JP
@jjw - read what I said. Yes I would lift off. Only an idiot would dab brakes mid-corner. And to be fair, only a driving idiot would brake mid-corner if they’d overlooked the entry speed, no need to be a god to know that much.
Pretty much everyone brakes mid corner at some point on a journey. I see it every day on the lanes on my way too and from work.
It was drummed into me when racing to brake before the corner but every day I see some eejit panic brake as they have gone in too fast (or they think they are too fast).
In fact its amazing how much unnecessary braking most drivers do. Driving at safe road speeds on public roads it should be possible to barely touch the brake pedal with proper planning and smooth driving and not bloody panic braking as soon as you see another car or a bend.
...esp...
No, it’s there to help keep the car in a straight line (if at all possible, of course!). There are some great videos on youtube demonstrating this – it really is very impressive.
As others have pointed out, it can’t undo the impossible – but it’s there to help prevent the car from sliding and to maintain it’s direction.
thats what I mean, a front skid will have a more linear progression without the pendulum effect of the rear end swinging around, therefore esp is more effective in controlling a front/ under steer kind of slide.
Once the rear end swings around it is surly beyond the ability of esp to correct it, granted the braking action of esp could stop this from happening in the first place, if the slide rear end movement is gradual. But isn’t that is when a rear wheel slide becomes dangerous?
It was drummed into me when racing to brake before the corner but every day I see some eejit panic brake as they have gone in too fast (or they think they are too fast).
Exactly - enter the corner at optimum speed so you can accelerate at the apex rather than be stamping on the brake in a panic somewhere in between nothing and something else.
The only time I have braked in a corner was when doing rally driving days with the fly off hand brake when I *wanted* the back end to hang out.
[i]read what I said. Yes I would lift off. Only an idiot would dab brakes mid-corner. And to be fair, only a driving idiot would brake mid-corner if they’d overlooked the entry speed, no need to be a god to know that much.
Exactly – enter the corner at optimum speed so you can accelerate at the apex rather than be stamping on the brake in a panic somewhere in between nothing and something else.
The only time I have braked in a corner was when doing rally driving days with the fly off hand brake when I *wanted* the back end to hang out.[/i]
Errr, what about real life? We are not talking about a spirited early Sunday drive through some scenic B roads with nice big sight lines, an empty oncoming lane and practically no traffic.
On Monday morning at 06:30 am, in the dark, in the drizzle and chain ganging along my local bendy A road with high hedges, there is no apex unless you want to mount the kerb. Entry speed is limited by the car in front. Oncoming motorbikes, wobbly cyclists, a tractor ferrying human sh!t to the fields results in queues or unexpected slow downs. Queues you may meet halfway around a bend, doing a sedate 35mph with a nice slippery manhole cover/deep puddle/split diesel just waiting to catch you out as you touch that brake pedal.
I hadn’t appreciated that the rear tyres were so important on FWD cars. It’s pretty stupid, then, that the garage advised us to only use winter tyres on the front...
(Notwithstanding the fact this was regarding a 4wd car - although to be fair they didn’t know that (but didn’t ask)).
The under steer vs oversteer thing is a valid point but I think irrelevant. Most accidents on the road are not caused by people getting into an over steering situation. You’d have to be driving very aggressively to get into that situation. Most people crash because they are not paying attention and leave braking too late so in that context i’d rather have the best possible braking performance.....especially in the wet, so newer tyre on the front for me too.
I think some people have an unrealistic view of the relative wear rates between front and rear tyres. You’re unlikely to en up in a situation where the rears are so old they’re degrading away.
After reading this thread I can only wonder why the tyre manufacturers and motoring organisations just plucked a random opinion out of their arses about where best to fit a new pair of tyres instead of thinking it through properly.
STW exceptionalism at its finest!
thats what I mean, a front skid will have a more linear progression without the pendulum effect of the rear end swinging around, therefore esp is more effective in controlling a front/ under steer kind of slide.
Once the rear end swings around it is surly beyond the ability of esp to correct it, granted the braking action of esp could stop this from happening in the first place, if the slide rear end movement is gradual. But isn’t that is when a rear wheel slide becomes dangerous?
I think we're both saying the same thing - ESP kicks in to help prevent the rear from swinging out in the first place - it dabs all four brakes independently to help keep the car in the intended direction. Watch the youtube in my link - it's quite old but good old Tiff demonstrates ABS, traction control and ESP.
Yes, so if it goes according to what the engineers have designed it should induce a bit of over or under steer to stop the skid angle becoming too great , therefore preventing a crash?
I’ll watch the vid when I’m off child duty and can concentrate.
Errr, what about real life? We are not talking about a spirited early Sunday drive through some scenic B roads with nice big sight lines, an empty oncoming lane and practically no traffic.
On Monday morning at 06:30 am, in the dark, in the drizzle and chain ganging along my local bendy A road with high hedges, there is no apex unless you want to mount the kerb. Entry speed is limited by the car in front. Oncoming motorbikes, wobbly cyclists, a tractor ferrying human sh!t to the fields results in queues or unexpected slow downs. Queues you may meet halfway around a bend, doing a sedate 35mph with a nice slippery manhole cover/deep puddle/split diesel just waiting to catch you out as you touch that brake pedal.
In your scenario I would be driving to the conditions and wouldn’t be in the position that I would have to brake mid/corner. If it DID happen, and I was driving too quickly for the conditions, there would be an accident. Whether the cause, other than driver error, would be tyre rotation choice or any other reason (worn shocks, under/over inflated tyres, failed suspension bushes, over-loaded weight in the boot, alien invasion, mumps or whatever) is anyone’s guess.
Ohh, and there is always an apex - it wouldn’t exist anywhere other than the optimum position on the road.
After reading this thread I can only wonder why the tyre manufacturers and motoring organisations just plucked a random opinion out of their arses about where best to fit a new pair of tyres instead of thinking it through properly.
STW exceptionalism at its finest!
Surely what makes a car safest and covering arse legally are both valid business decisions?
One just has a lower moral motivation, one keeps the customer coming back and the other stops their family suing you, both improve profits.
Personally I go with the tyre engineers advice to put new on the back. Incidentally, two large tyre companies have told me that winter tyres all year round are better than summer all year round.
That is incredibly bad advice and goes against every bit of advice given about fitting winter tyres. It is highly likely that the winter tyres on the front will let you get up to a speed the rear wheels wont cope at and send you spinning when you try to brake or lose speed round a turn. Only way to correct that is keep using the front wheels to pull the car straight, like a car with a waggling trailer.
IIRC the only remotely acceptable position to only fit 2 winter tyres, if you must, is the rear of a RWD car which sounds mad to most people as they think about steering but on the rear driven wheels it means you have traction grip for moving off and rear grip for stopping. Even that is only a "if you must do it" and obviously the best way is all 4 tyres.
Costco tyre fitters are not allowed to fit new tyres to the front, unless there is a valid reason such as different sizes. Possibly something to do with them being a US company and some law or previous legal case following an accident.
I have seen people argue that they want them on the front and they will flatly refuse to change the tyres at all.
That is incredibly bad advice and goes against every bit of advice given about fitting winter tyres.
I think you have misunderstood what I was saying. It was a tangential point, their advice was that if you have only one set of wheels then 4 winter all year round is better than 4 summer. That was back in 2011 when both Continental and Michelin did not have all season tyres in their UK range. Michelin advised this over the phone, I will see if I still have the email from Continental.
I agree with what you say and it amazes me that I have heard tyre fitters advising ‘just winters for the front’
Some weird answers on here!
If you’ve ever raced a FWD car on track in the wet especially, you’ll realise why rear tyres are so important. Passive rear steer (accentuated with low tread on rear tyres) will mean that the rear of the car will let go pretty quickly if you do something like lifting off the throttle abruptly mid corner. There’s not much weight over the rear of a front wheel drive car, so there’s not much pushing the tyres in to the ground.
Contrary to what you might think from TV shows and car magazines, catching the oversteer in the limited amount of space you have on a public road is pretty hard.
Worn tyres on the front will promote understeer, which is much easier for most people to deal with – easing off the power gently will usually bring the front back in line.
JP
Yes but PEOPLE ARE NOT RACING ON THE PUBLIC ROADS so therefore so what.
For braking in a straight line you want the best rubber not the front, especially in the wet, and that is how most accidents happen. People crashing into cars in front of them in a straight line or something unexpectedly coming out in front of them, and not racing around bends, overcooking it massively such that they snap into oversteer. Depends if you want to configure your tyres for the most likely scenario or the least likely scenario.
If you get into a situation where you're getting a FWD car into snap oversteer...1. you deserve to spin off into the hedge and learn a valuable lesson in life - roads are not race tracks and 2. the chances are better and slightly grippier tyres on the back would not have saved you because you were driving like a dick.
Also the expert advice on this is not clear cut in that it is not better to have the best tyres on the back in ALL circumstances. there're pro's and cons to each option in different situations so there is not one rule to rule them all. According to Michelin the advantages to better tyres on the front are better grip and braking in wet and dry, and the advantage of having the better tyres on the rear is better braking on a bend on wet roads. So for me the better option for most situations out on the road are better tyres on the front and when entering a bend when its wet I'll just shave off a bit more speed than usual when approaching the bend.
bsims did you edit your post as I could swear you said something about being told to put 2 winters on the front?
Winters all year are okay, as long as you don't mind the squirmy handling all summer and excessive tyre wear. You could argue that your summer braking is now compromised as the braking distance in summer will be longer with winter tyres but you should not be driving on the limit on public roads anyway so it should not make as much difference as the tyre tests suggest and the benefit in cold weather is much more significant.
Most accidents on the road are not caused by people getting into an over steering situation.
On my usual work commute there's one bit that catches people out with a 90 degree bend after a decent 60mph(+) stretch, it's probably 50/50 whether they end up forwards in the ditch, understeer, Vs backwards in the ditch, oversteer 😁
Having been in a few oversteer incidents on the access road at work I can personally vouch for new to the rear as that stopped it happening. Never had the front at the point where the tyres couldn't cope.
Waiting on anecdote not data comment...
@ andyl. No edit, as the point was not on topic I guess its easy to mix up points.I was initially writing about my thoughts, that front wheel skids are easier for esp to sort out. I know I often think a post says one thing and when reread I find I have misread the post. That's not meant to sound condescending.
The guy at Michelin said you will easily reach the limit of a summer tyre during a cold winter but you would have to try to exceed the limit of a winter tyre in a UK summer.
The Conti guy provided tech details, about relative performance of both in the wrong and correct seasons and finished by writing if it was his family car and he had to choose, he would have winter tyres.
Both companies clearly stated that it was not ideal though.
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I hadn’t appreciated that the rear tyres were so important on FWD cars. It’s pretty stupid, then, that the garage advised us to only use winter tyres on the front…
I've done this- with sensible allseasons on the back- and it worked great. For me. It's completely shit advice, though, because it might not work great for you and if it doesn't then someone's likely to get squished.
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(basically, if you still drive cautiously and well within capability, and treat the extra grip as like a trump card you can use occasionally, it's a useful bonus. If you try and use that grip all the time, it's backwards through hedges. You need to drive almost all the time to the capability of the rears and it's constantly tempting even to a good driver to drive to the capability of the fronts.)
What the ‘ell are you on about?
I agree with your working. But that's not what you said in the original post.
if you just keep changing the fronts then it can get to the stage where the rears are perishing due to age. You will also have a much longer time with low tread depth on the rear as the wear period is stretched out.
Although I'll concede you probably meant you have a longer time relative to rotating tyres, that reads that wearing a set of rear tyres out over ~40k (so 20k at less than 50%) is different to say 4x fronts at 10k intervals with 4x 5k = 20k at less than 50%.
Although it does raise a question, if the fronts are almost worn out and you new tyres on the back, does that tip the balance too far.
I've rotated my winter tyres as I reckon by next summer the better ones (now on the front) will be equal or worse than the rears.
Having been in a few oversteer incidents on the access road at work I can personally vouch for new to the rear as that stopped it happening. Never had the front at the point where the tyres couldn’t cope.
I think whoever did that needs to learn to slow down .
"I think whoever did that needs to learn to slow down"
Or if it's anything like the kind of access roads i use at work it's the perfect place for some fun being blocked off to the public , wide , clear , gravelly and with gates at either end that I have the keys to so won't meet anyone.
Hilux slidez (accidentily of course)
Still struggling to see any logic to not put the good ones on the rear.
Still struggling to see any logic to not put the good ones on the rear.
Perhaps in a safe environment when you want to push it, but on an open road just drive like a grown up?
I put new rubber on the front of the mighty old Galaxy this morning. Rears are about half worn. I did ask about swapping them but they said fine as they are. A bit more wear on the rears he reckoned they would have recommended swapping them.
i used to it part worn second hand remoulds or anything tyre shaped on my motors but after having a blow out & rolling a car some years ago I don’t piss around with tyres.
Tina's - I said if you just keep replacing fronts ie fitting the new to the front all the time. And thus your rears will continue to wear slowly and thus be at low tread for longer, admittedly whenever they get there.
My little workings above show why it is more sensible to have new on the rear regardless of grip when new. Grip when old is probably even more important as you could be driving round for a few winters with rear tyres between 3mm and the legal limit which will mean they may not perform as well in standing water or with mud on the road.
Granted Michelin did do a study claiming their tyres performed right down to the limit in the wet but not sure how representative of all tyres, all cars and all conditions that is.
Thinking back tha might have been due to their straight cut tread unlike most tyres where the tread grooves taper so actually narrow towards the tyre carcass so as the tyre wears the groove that moves water gets narrower so in that initial contact you get less displacement. It is only when the groove cannot cope water volume wise that the depth comes into play.
"Perhaps in a safe environment when you want to push it, but on an open road just drive like a grown up?"
Surely the same rule numbern1applies. Still doesnt excuse not utting the new tires on the back.but I've yet to sees decent arguement not to - but there's also the you don't get lulled I to a false sense of security in that well the fronts are gripping so I'm good..... See it all the time In winter round here wjth the 2 winter tire bregade going off the road backwards when it let's go .
tndyl 'spoint<span style="font-size: 0.8rem;"> is the one for me though .i don't want to end up with 10 year old perished tires on the back of my car. Been in a van that's had a blow out due to exactly this ..... </span>
Rule number 1 is like ppe- it's the last line of defence not the first.
Or if it’s anything like the kind of access roads i use at work it’s the perfect place for some fun being blocked off to the public , wide , clear , gravelly and with gates at either end that I have the keys to so won’t meet anyone.
Na, it's a public road, with a cycle path crossing it. Lots of EDF employees treat it like a race track mind.