| Archive for NEEPS North East Eco-friendly People's Site |
| wildgarlic |
Winter TyresI've just read Stoney's latest blog entry about the way the wintry weather has caused school closures and it reminded me that I need to get winter tyres for my car.So. My friend recently had 2 winter tyres put on her car. Is it better to have all 4 tyres as winter ones? What is the difference between snow tyres and winter tyres? Obviously money! I've been quoted £66 per tyre for non winter type and I think it was £92 for the winter ones. We have looked at buying a full set of wheels with winter tyres on (second hand from Ebay) and that is about the price of 2 new winter tyres. |
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| Smooth Hound |
sounds like a better idea to me, you could keep them for next winter then as well. | ||||
| Stonehead |
Always fit winter tyres in fours. If you fit a pair, you upset the braking balance. (And if your car has 4WD you can wreck the drive train due to the different levels of traction between pairs of tyres.)
Winter tyres are intended for temperatures below 7C, and are mainly intended for rain, slush and occasional snow. They improve traction but, more importantly, reduce braking distances on slippery roads. Snow tyres, as I have on the Defender, are for serious snow and ice, as well as rain and slush. Ours are even drilled for studs, but we don't use them. (If the snow is that serious, I'm staying home!) Googling threw up this backgrounder on winter tyres from Continental. |
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| Stonehead |
And this from Michelin on fitting winter tyres to just two wheels. | ||||
| Stonehead |
Oh, and I'm not just basing this on tyre manufacturer's info. I used to work on various motoring magazines and we did quite a bit of research at various times.
I've just had a look on Autocar, one of my former employers, and they have a short, recent article on winter tyres aimed at getting drivers to reveal their opinions. |
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| IainC |
Yup... while fitting winter tyres to only one axle won't actually knacker a 4WD vehicle, you will risk spinning it.
Winter tyres as mentioned work below 7 degrees, which in our region is a good few months of the year. I've not yet got a set fitted to the scoob, but my wifes Leon has been running a set of Michelin Pilot Alpin PA2's for a while now (bought them as a winter set for last year and she hasn't noticed any issues when using them in summer so never bothered replacing them). They include a lot of small sipes in the tread which help grip the snow and mean that her FWD car seems to have as much grip/ability as my 4WD car (on summer tyres). Best bet (IMO) is to buy a second set of wheels and fit winter tyres to them, most of the guys I know doing this (running scoobs) have managed a good few winters out of the one set of tyres (one guy is on his 5th winter so far with plenty of tread left yet) and it also means that your summer tyres don't get used as much so save you replacing them as quickly. Also means if you are running with alloys on, the salt is less likely to affect your "good" set. IIRC, you can also get winter tyres and get a thinner tyre (assuming you get one with a deeper sidewall to keep the speedo correct) which may help as well. I know generally the narrower the tyre the better grip I've had in the past. The mud/snow tyres I had on the Disco would have been okay, but as Stoney says are really more for extreme conditions and you'd not need/want them on your car. By the time you need those kinds of tyres, generally you will find in a car you have run out of ground clearance anyway. Extra set of wheels/tyres might cost you now, but whats your excess? how much more would your insurance be next year if you had a bump? can you afford to not have a car at this time of year while it's away being repaired? |
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| IainC |
Studs are illegal in this country IIRC. |
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| Smooth Hound |
sounds like you would be best with the full set off the ebay then, unless youve got 400 quid to spare, | ||||
| Stonehead |
Actually, it can knacker the drivetrain due to the different rotational rates of the different tyres, which leads to transmission wind-up. I've seen a Defender with a trashed transfer box due to this. It can also happen if you fit new tyres to one axle and not the other, even if they are the same make and tread pattern. If you check the manuals for many cars with permanent 4WD, you'll often find a warning to this effect. |
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| IainC |
Have seen/heard this argument quite a few numbers of times. One question for you then... each tyre (regardless of size) touches the ground and is connected to the vehicle via the diff on each axle, and on most 4wd cars, with a centre diff. Now (4wd or not) when you turn a corner, the tyres on one side of the car travel a LOT further than they do on the other side. Surely if the transmission was so iffy that a slight difference in circumference meant it'd kill itself, it'd do it anyway due to you cornering (unless you also ensure you do as many left hand corners as you do right hand ones  )
Generally though, I do always replace tyres in fours. Have experienced replacing tyres on one axle before and having the back come out on a roundabout (large Audi estate... I put on Bridgestones and they'd fitted cheap "hedgehunters" ). Have had cheap cars when I was growing up though that were fitted with a single tyre at a time due to lack of cash and not one of them had any transmission issues (in fact none of my cars have ever had transmission issues).
Another "potential" issue, would be running a space saver tyre that a lot of manufacturers fit these days... IME none of them are ever the same dia/circumference as the std wheels and you don't see any warnings on the space saver tyres about your transmission. Also, IME, the front tyres get shredded far quicker on most cars than the rears (even on AWD cars) due to the front wheels doing the steering and driving, yet to see that having an effect either. Not saying you've not seen a car/4x4 that the transmission has failed on, but there may be additional factors (lack of oil in it for a start... you did mention landy ) that contributed every bit as much as iffy tyres.
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| IainC |
You've reminded me about a guy who had a scoob and who replaced all four tyres on it at the one time for a decent performance set (that he'd had before, so trusted them)... the car simply didn't handle as it should have on the new tyres... he tested the pressures and checked each tyre individually to see if he could spot any issues with them and couldn't see a thing wrong. Ended up he just couldn't live with it and took it back to the tyre dealers and said what the problems were... they couldn't understand it either but agreed on testing that something wasn't quite right with it. They did some investigation and found that 3 of the tyres had been made in one factory and one tyre in another one. They fitted a forth tyre from the first factory and the car was back to normal... just goes to show that even brand new tyres of the same brand and type, can still not be identical. It's the kind of thing that maybe wouldn't have shown up so easily/quickly on something that wasn't a performance car IYKWIM (ie a 70yo who drives everywhere at 25mph peering thru' the steering wheel to see where she's going )
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| Stonehead |
First, I didn't say we used studs. We have snow tyres that can be fitted with studs should conditions warrant it. We've had some fairly significant snow here, but it's never been serious enough or persistent enough to warrant buying studs, much less fitting them. Second, studs are not illegal in the UK. The relevant law is the Road Vehicles (Construction and Use) Regulations 1986 (C&U). Regulation 27 (1)(h) of the C&U states that tyres should not be used on the road if:
In other words, if you're driving on the public highway with snow tyres that have studs fitted, then you'd have to show very conclusively that they were not damaging the road. Similarly with snow chains. (And yes, I do have a rather large pile of law books to hand.  )
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| Stonehead |
From the tech notes for the Volvo V70 Cross Country (so not a Land Rover and not due to lack oil).
I think that covers all your objections. I've seen similar advice from quite a few other manufacturers. When I was working for Haymarket, publisher of Autocar, What Car magazine had quite a long battle going with Volvo after the centre diff of one of their AWDs failed. The owner had replaced a very worn but still legal tyre with the unused spare. |
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| IainC |
Yeah, but generally in this country an entire trip will not require studs on the whole journey and who's gonna stop to remove them... hence generally if you were stopped with studded tyres the police would want a word (although I remember when I was young the Forestry commision LR's passing our school must have had them fitted due to the noise  )
Never said you used them though
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| IainC |
You never answered the turning corners aspect though (which no car manual ever does). Surely if you sat on a constant radius at 60mph for 100,000 miles you'd probably not see any issue with the transmission? I've had a few AWD's now, some had tyres on one axle replaced and some had all four replaced at once (I always fit them on the front wheels anyway, although most tyre places want to fit them to the rear). Never had a transmission issue yet, and in the case of two AWD's I've added "at least" 50% more power/torque and done nothing differently to normal. In one case after doing all that I ran the car for ~70,000+ miles and still didn't have an issue with the transmission. Most car manuals are written to give get out clauses for the manufacturer IMO. For example I seen/heard someone, who's mum ran her Micra for a good few years and was surprised to hear that she needed oil to run it... it had NEVER been serviced in it's life and she'd only ever lifted the bonnet to put more water in the washer bottle... after so many years the engine seized solid, but it went YEARS without any maintenance. You mentioned someone claiming against Volvo when their centre diff was knackered... but surely if one tyre out of four was knackered then the diff on that axle would have taken as much of the brunt of the "problems" as the centre would have? Certainly my current car allows me to run a fully open diff (and various stages of front to rear bias and locked), but even on previous AWD cars, I never found any issues. |
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| IainC |
BTW, not getting at you about it. Just that I've seen the same argument about it over and over on various car related sites and not one person yet has managed to fully answer the fact that due to turning, the 4 wheels on a car NEVER do the same distance EVER.
Obviously it's best to try and do what you can to mitigate against having issues though. |
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| JamesB |
winter tyres on 2wd drive carjust wondering about winter tyres on a 2wd drive car. most of what I've seen here is to do with 4wd drive and there is obviously makes sense.I currently have winter tyres only fitted on the drive train (front wheel drive car). I didn't think it was worth fitting to the rear, is it really worth it? In my very basic understanding of whats involved, i thought they are just being pulled along by the front and wouldn't make a real difference. Is the braking really worse with winter tyres at the front and normal tyres at the back as opposed to 4 normal tyres? Traction is what im really after so I can get out of the house. JAmes |
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| IainC |
I'd imagine braking when going round a corner would be a h*ll of a lot worse when you just had the winter tyres on the front of the car.
Personally I'd not mess about with "odd" tyres on the car. Always like to keep front and rear the same as much as possible (that goes for the wifes FWD Leon too). |