New Tyres Front or Rear? (re Have you ever worn out the tread on your tyres, Reloaded)

[MotoHomer]

This follows on from the earlier thread (in brackets) but is of broader interest so I've retitled slightly. Suggest you read original thread before proceeding with this one! It's also a bit long, so better make a brew.

The issue, raised as part of the other thread, is whether to fit new tyres (as an axle set) to front or rear. I can confirm REAR based on unfortunate personal experience. Read on.

Some years ago I bought a classic car as a retirement toy. The very first thing I did was replace the front tyres, which were worn. After research I opted for a pair of Uniroyals as they had good reviews for wet weather grip. A national chain of tyre fitters popped them on the front. Job done. The rears were also worn but perfectly legal. OK for a while.

Some time later I was returning from a local shopping trip with family on board. Extremely wet afternoon with numerous thundery downpours. Easy rural road very wet but driven by me many thousands of times in all weathers and extremely well known; no probs. My history? 900,000 miles covered over maybe 30 years, all roads, all conditions inc snow/ice, no probs. Clean licence too. I'm careful. We were cruising along at about 50 mph as I entered a moderate, slightly off-camber bend, neutral throttle, 5th gear, smooth turn in.

The rear broke away - absolutely no warning, no provocation just an abrupt, total and catastrophic loss of adhesion, like hitting water-ice.

We spun but remained on the road. We were so very lucky - no injuries, minor damage to the car. But I just could not understand what had happened. Nothing in all my experience could even start to explain it. The road surface was worn smooth but there was no mud or oil. I was genuinely baffled.

I began researching.

Another national chain of tyre fitters, a motor accident investigator, the Police and a tyre company boffin (none involved in my incident incidentally) all confirmed that having new/best tyres on the front was inherently unstable and would predispose the vehicle to exactly the loss of adhesion which ocurred and which is demonstrated in the video link on the original thread. The investigator had in fact suffered an identical incident himself once with a similar tyre set-up, before he had learned better! Tyre Depot Manager said they'd never advise fitting new tyres to the front. Should've gone to them in the first place.

I basically had loads of grip up front and not enough on the rear, which had aquaplaned and let go. Rears were still legal by the way but clearly not up to the extremely wet conditions.

Believe me you do not want this to happen to you. I warned you this was a bit long but I hope you can understand why!

The point is;

New (or best) tyres on the REAR axle. Definitely. Always

Safe motorhoming.

 

[Clive]

If the new tyres were on the back the front would have broken away first. Then what?

No brakes but no steering either!. At least with new tyres on the front you can use oposite lock to counteract the back end going for a wander. It always worked for me with an old BMW I once had.

Perhaps its just that your reactions were too slow or you were just not driving according to the road conditions.

 

C.

 

 

 

[rupert123]

This would seem a pointless argument, it depends on whether your vehicle is front or rear wheel drive. If only buying a pair they should go on the driving wheels, at least you would then have some control if you 'lose' the non driven end. In my years of special stage rallying and rallycross you try and keep good tyres on all four wheels but control is always maintained by the driving wheels. Other things come into play, of course, but grip is certainly more use on driven wheels.

[lennyhb]

rupert123 - 2010-02-03 5:06 PM

 

This would seem a pointless argument, it depends on whether your vehicle is front or rear wheel drive. If only buying a pair they should go on the driving wheels, at least you would then have some control if you 'lose' the non driven end. In my years of special stage rallying and rallycross you try and keep good tyres on all four wheels but control is always maintained by the driving wheels. Other things come into play, of course, but grip is certainly more use on driven wheels.

 

Quote from Michelin:

 

"Whether you have front or rear wheel drive, we recommend that you use newer tyres for the rear set, for extra safety in unforeseen or difficult situations (emergency braking, tight bends etc) particularly on wet surfaces."

 

Full Michelin blurb:

 

http://www.michelin.co.uk/michelinuk/en/car-4x4-van/less-worn-tyres-rear/20070314172074.html

 

 

[Clive]

Well,

It doesn't convince me.

Steering and brakes would always be my priority so best tyres on the front axle always.

You don,t see lorries with remoulds on the front steering axle, but frequently on the rears.

 

But its only my opinion. I am no expert on tyres.

 

[Guest Tracker]

The main issue is that with front wheel drive vans the front tyres will probably wear out well within the five year life span of tyres whereas the rear ones would probably last twice that long - if not more - if allowed to run their course.

 

If you wear out the fronts and buy two new ones without switching them back to front you will then need to buy two more for the rear long before they wear out.

 

I try and switch mine back to front and front to back at about 18/22,000 miles that way they should all wear out at more or less the same time.

 

I know it means buying four tyres at once instead of two but there are some good deals around when you buy four!

 

Then again if you include the spare in the switching cycle and are prepared to move them around more often you can get all five to wear out at the same time and just keep the best one as spare.

[rupert123]

lennyhb - 2010-02-03 5:37 PM

 

rupert123 - 2010-02-03 5:06 PM

 

This would seem a pointless argument, it depends on whether your vehicle is front or rear wheel drive. If only buying a pair they should go on the driving wheels, at least you would then have some control if you 'lose' the non driven end. In my years of special stage rallying and rallycross you try and keep good tyres on all four wheels but control is always maintained by the driving wheels. Other things come into play, of course, but grip is certainly more use on driven wheels.

 

Quote from Michelin:

 

"Whether you have front or rear wheel drive, we recommend that you use newer tyres for the rear set, for extra safety in unforeseen or difficult situations (emergency braking, tight bends etc) particularly on wet surfaces."

 

Full Michelin blurb:

 

http://www.michelin.co.uk/michelinuk/en/car-4x4-van/less-worn-tyres-rear/20070314172074.html

 

 

This is Michelin playing safe, much as they do when you ask about tyre pressures, ask any rally driver who drives on loose surfaces and they will tell you differant. Michelin have to allow for drivers who have never learnt anything beyond passing their test. Go on a 'skid pan' with someone who can drive you will soon see what I mean.

[lennyhb]

Tracker - 2010-02-03 5:49 PM

 

 

Then again if you include the spare in the switching cycle and are prepared to move them around more often you can get all five to wear out at the same time and just keep the best one as spare.

 

Good idea in theory but the van looks silly with 3 alloys & 1 steel wheel. (lol)

 

 

[Guest Tracker]

lennyhb - 2010-02-03 5:56 PM

 

Tracker - 2010-02-03 5:49 PM

 

 

Then again if you include the spare in the switching cycle and are prepared to move them around more often you can get all five to wear out at the same time and just keep the best one as spare.

 

Good idea in theory but the van looks silly with 3 alloys & 1 steel wheel. (lol)

 

 

My van has an alloy spare wheel - so there!

[colin]

rupert123 - 2010-02-03 5:53 PM

 

lennyhb - 2010-02-03 5:37 PM

 

rupert123 - 2010-02-03 5:06 PM

 

This would seem a pointless argument, it depends on whether your vehicle is front or rear wheel drive. If only buying a pair they should go on the driving wheels, at least you would then have some control if you 'lose' the non driven end. In my years of special stage rallying and rallycross you try and keep good tyres on all four wheels but control is always maintained by the driving wheels. Other things come into play, of course, but grip is certainly more use on driven wheels.

 

Quote from Michelin:

 

"Whether you have front or rear wheel drive, we recommend that you use newer tyres for the rear set, for extra safety in unforeseen or difficult situations (emergency braking, tight bends etc) particularly on wet surfaces."

 

Full Michelin blurb:

 

http://www.michelin.co.uk/michelinuk/en/car-4x4-van/less-worn-tyres-rear/20070314172074.html

 

 

This is Michelin playing safe, much as they do when you ask about tyre pressures, ask any rally driver who drives on loose surfaces and they will tell you differant. Michelin have to allow for drivers who have never learnt anything beyond passing their test. Go on a 'skid pan' with someone who can drive you will soon see what I mean.

 

So why I wonder why do F1 drivers prefer their fronts to lock to the rear? are they a bunch of amatuers who haven't learnt to drive?

But lets get back to the real world.

Back in the day when my reflexes where much sharper than now I had a rental van swop ends because the rears where badly worn, at the time I was well used to driving my phaeton on the throttle esp. in the wet, but that helped me not at all.

[lennyhb]

Tracker - 2010-02-03 7:21 PM

 

lennyhb - 2010-02-03 5:56 PM

 

Tracker - 2010-02-03 5:49 PM

 

 

Then again if you include the spare in the switching cycle and are prepared to move them around more often you can get all five to wear out at the same time and just keep the best one as spare.

 

Good idea in theory but the van looks silly with 3 alloys & 1 steel wheel. (lol)

 

 

 

My van has an alloy spare wheel - so there!

 

 

Well at least I've got a spare more than can be said for a lot of vans these days.

 

 

[teflon2]

Hi I'm in total agreement with Barry best treads on the front, I can catch a rear wheel drift but if I lost the front end I'm just a passenger. Used to slide the back on a rear wheel drive before I grew up and traffic got so heavy, must admit wouldn't like to try it on 7+meter motorhome. Every ones different so do what feels right to you. :-S oops it should read Clive must go and have a brain retread.

[jhorsf]

a very good post of advice Motohomer and Colin but remember you can take a horse to water, do not expect some posters to agree as they have there own opinions, even if they contrast with every tyre manufacturer in the world.

That is why it is illegal to have radial on front and crossply on rear you fit the tyres with the most grip to the rear ie. the radials and crossply on the front.I do agree with one thing you said Clive you are no expert on tyres (lol)

[jhorsf]

Still not convinced watch link

 

http://www.michelinman.com/tire-care/tire-basics/reartire-change/

 

http://fishtail.tv/tire_manufacturers_recommendations.html

[W3526602]

Hi,

 

That was my thought too. Vintage/classic car, probably fitted with X-plies when new. Fit Uniroyals to the front ....... ???? Unlikely, considering the driver, but worth a query.

 

Query aquaplaning in a classic car? Not impossible, but not likely either, tyres too narrow.

 

Knackered shock absorbers, hit a little bump on a bend, car jumps sideways. I've had that happen in a 1962 Vauxhall Victor, at little more than a walking speed, tight U-bend, severe camber. Quite alarming. Also very hairy Scimitar GTE with knackered rear suspension, could bunny-hop sideways on fairly smooth bend if any power applied ...... stripped teeth off differential.

 

602

 

 

[neilmac]

I commented in the original thread with my opinion being contrary to the modern 'industry' advice.

 

I am still of the same opinion based simply on the FACT that there is some chance of controlling a rear wheel skid - there is virtually no chance of controlling a front wheel skid as you have no directional control.

 

Grip should be best on the steering wheels and, if that's on front wheel drive then so much the better.

 

Bottom line is each to their own, and the best way to avoid the problem in the first place is to drive according to the conditions, your vehicle's drive configuration and your experience - in my opinion :-D

[Brambles]

For goodness sake - WATCH the video. You saw the one in the last thread..here is another.

 

 

[Brian Kirby]

There is a world of difference between rally and track cars, and the techniques used by their drivers; standard passenger cars and their drivers; and motorhomes and their drivers; and trying to apply the practises and logic of one group to the others is not going to help anyone.

Someone who is used to power sliding a rear wheel drive car (with sufficient relative power to control the slide), is liable to find the technique misfires badly if applied to a front wheel motorhome with a fraction of the relative power and a much higher centre of gravity.  I strongly suspect they would find themselves watching the land replace the sky at the top of the windscreen, as their motorhome disintegrated around them!

The advice given by Michelin et al is intended for the average person driving the average car under average conditions, not a stripped out rally car with 400hp and four wheel drive, whose tyres will be specials and in any case will last for only a few miles.  This is advice for the lady curate on her way to afternoon tea with her parishioners.  So, lets set the boy-racer element to one side.

More people, on average, will get into worse trouble if the rear end goes on a bend, because they will do the wrong thing and steer the wrong way, than they will if the front end goes.  Besides, 50% of the time all that beckons is the hedgerow, or the ditch, in either event.  For the other 50%, when the skid will carry you onto the opposite carriageway, drivers will sense that the car is not steering as it should and will at least stop accelerating, even if they do try to tighten their line.  Generally, front end breakaway is fairly gentle because cars are designed to behave that way, and the speed just scrubs off.  Backing off is often all that is required to restore control.

If the rear breaks out, on the other hand, which is not how the modern car is supposed to behave, it will almost invariably be because the rear tyres are worn, or tyre inflation generally is wrong.  Under these circumstances, the front retains grip but the rear does not behave controllably, but whips out of line rather than progressively sliding.  Even backing off won't work, because the reaction is too quick to be caught, and braking will just exacerbate the problem.

Obviously none of these problems arise if speed is kept within the capability of the driver and the car, so a skid only arises when one, or the other, is exceeded.  Whatever the cause, often a misjudgement, and often not appreciated by the driver, the car is now out of its driver's control and what happens next will be decided by the inherent dynamics of the car, and luck.  Under these circumstances, be it motorhome or car, the safer overall situation is for the better tyres to be at the rear, since that is where the most common driver reactions, and vehicle dynamics, combine to allow loss of speed and (hopefully) an eventual recovery of control, with lowest risk.

The safest advice for any driver, under any circumstances, driving pretty much any vehicle, is to put the best tyres on the rear.  That is what the film demonstrates, and it is why the advice is given.

[Brambles]

I have set up a pole for the question of rear or front.

 

http://www.outandaboutlive.co.uk/forums/forums/thread-view.asp?tid=18543&posts=1

Jon.

 

[GypsyTom]

It would appear that every tyre manufacturer is adamant that new tyres should go on the rear. We have seen videos explaining why, for ordinary drivers, this should always be the case.

Yet there are still people on this forum who think that they should go on the front! What does it take to convince people that their long-held assumptions, which are really based on no evidence whatsoever, are wrong?

[rupert123]

A quick look at the pole seems to indicate no one is convinced.

 

Brian as I stated on an earlier post I have a lot of experience in the Rally and rallycross world, plus a little circuit racing. I admit it was a while ago in the 70's/early80's but had a fair amount of success in both rallying and rallycross, circuit racing not much and the techniques to control a skid that has not been induced are exactly the same. I tend to agree that a sliding van would not be much fun and your chance of controlling it not high but disagree about which is hardest to control. I feel most are fully aware about turning into a rear wheel skid and would do it automatically but a front wheel one is going to end in tears. I looked at the films and they are not realistic, the cars are being driven on a road turned into a river at a speed that is bound to create problems. If anyone drives like this in these conditions then they deserve all they get, the worn tyres were also below what I would personally consider safe anyway. I agree that we should be talking in practical terms, about M/H's, so when you replace the two worn tyres the remaining ones will still be in good condition. In these circumstances new tyres should always go on driven wheels.

[trooper]

Yes, lets forget about cars, M/Hs have completely different needs, mainly traction from the driving wheels, and steering control because of the weight and high centre of gravity.

Question,have anyone driving a M/H normally had,1, a rear slide out, 2,the front wheels spin,

Answers on a post card to.

[GypsyTom]

trooper - 2010-02-04 5:07 PMYes, lets forget about cars, M/Hs have completely different needs, mainly traction from the driving wheels, and steering control because of the weight and high centre of gravity.Question,have anyone driving a M/H normally had,1, a rear slide out, 2,the front wheels spin,Answers on a post card to.

Occasionally I get front-wheel spin on my front-wheel-drive motorhome. It's usually when taking off on a hill when it's wet.

It's unlikely that this kind of front-wheel spin will kill me. However, in an emergency, if I have to brake sharply when driving round a bend in very wet conditions, the poor adhesion qualities of worn tyres on the rear may well send me spinning and result in a serious accident.

[Guest Tracker]

trooper - 2010-02-04 5:07 PM

Question,have anyone driving a M/H normally had,1, a rear slide out, 2,the front wheels spin,

Answers on a post card to.

 

1 no never yet in 35 years but it could happen tomorrow?

 

2 yes lots of times on grass and on hairpin bends on steep hills or if I have had to stop on a very steep hill in the wet or on a loose surface.

 

I too subscribe to the best tyres on the back theory except when changing them round to even out wear means that the fronts have 3 or so mm more than the backs for a few thousand miles - but even then the backs would be certainly no less that half worn with 4 to 5 or so mm to the fronts 7 to 8 (ish). There is no way I am driving three and half tonnes of van around with less than 3mm on any of the tyres.

[Brian Kirby]

rupert123 - 2010-02-04 4:10 PM .............. I feel most are fully aware about turning into a rear wheel skid and would do it automatically but a front wheel one is going to end in tears. I looked at the films and they are not realistic, the cars are being driven on a road turned into a river at a speed that is bound to create problems. If anyone drives like this in these conditions then they deserve all they get, the worn tyres were also below what I would personally consider safe anyway. ...............

Regarding the understanding that one should turn into the slide, Henry, I'm afraid I'm less convinced than you are!  It is counter intuitive, and relatively few drivers have actually tried it while panicking.  I also think, based on some past conversations, a surprising number understand the phrase to have exactly the opposite meaning to what is intended.

Most who seem to come unstuck are either young and inexperienced, and possibly somewhat over exuberant, or simply caught out by circumstance.  Of course, deliberate risk taking such as you suggest must be part of the story, but is surely a very small part?  I think the advice is aimed at the majority of slightly inattentive, capable but not fully competent, drivers, driving inherently understeering, mostly front wheel drive, modern cars.  I have no experience of ASR or stability, programmes in action, but suspect that they, too, are set up on the assumption the best adhesion will be at the rear. 

It isn't the counsel of perfection, it is the lowest common denominator: the advice that gets the greatest number of the dozy muppets (there, now I've gone and said it!) out of the poo most of the time!  :-)