Tyre replacement.

[Jem]

I am just wondering what people's thoughts on replacing tyres. I have a set on the rear which are made in 2012 so they are getting on a bit.

There are some small cracks on the side wall. Nothing big but small hurling cracking. There is plenty of tread left on them.

Is it worth getting them changed now or just wait until they get older.

[sparky Paul]

You could just go by the 6 year rule, but tyres deteriorate at different rates under different conditions. I've fitted and used tyres that were older than that, so long as they have been stored correctly and are in good condition, they are fine.

Tyre wall cracking is not a major issue, so long as it's not so deep as to expose cords. An MOT tester will do a visual check and advise on cracking, or fail it if looks dodgy, so you should get some warning that they are on their last legs.

What you should watch out for is any cracks developing in the root of the treads. Any sign of this, and you should think about replacing the tyres ASAP. If you can see any cord at the bottom of the cracks, then get them swapped immediately.

Chinese tyres seem to be particularly prone to age cracking relatively quickly. I tell anyone who does low mileage to steer clear of them.

One other point, front wheel drive cars wear the rear tyres relatively slowly, and it's not uncommon to have to swap old rear tyres due to perishing. To avoid this, normally when I put a pair of tyres on, I put the new pair on the back, and put the back ones on the front. That way, the tread gets used before you encounter any age related issues. You should always have the best pair of tyres on the back, in any case.

[peteo48]

I agree with sparky. On my previous Jazz the rears got very perished (cracks between the threads) and I decided to replace them (they were about 5 years old and had a lot of tread) although they had passed an MOT easily. On my current car there was little or no cracking so I moved these to the front in November 2016 when I replaced the fronts which were down at 3mm.

Oddly, this car has the same Dunlop SP2030s as the old car but cracking hasn't been on issue on this car.

[sparky Paul]

It can seem completely random, but where a car is parked daily often plays a part. That said, there are so many things that can affect tyre rubber.

Condition is largely down to MOT tester's discretion, and some are keener on tyres than others. Bad tyres sometimes pass MOTs, on the other hand, some folk are sold tyres when they don't need them. The best advice is to get down and have a look at them once in a while, and be wary if you see any cracking in the tread roots, particularly if you see exposed plys.

[Jem]

Thanks for the advice I will go and have a look in between the tread and see what it looks like.

[ondatony]

I`m a little confused by sparky Paul`s comment about "always having the best tyres on the back", as I always understood that as the front wheels drive,(on most cars these days), steer, and take the majority of the braking load, the "best tyres" should be fitted to the front wheels. Or was this just an "old wife`s tale? (Probably best just to have decent tyres on all wheels).

[Jem]

I did some reading online and it seems to be a myth about having the best tyres on the front. Apparently the back is better.

[culzean]

I did some reading online and it seems to be a myth about having the best tyres on the front. Apparently the back is better.

On a bend on a flooded road with 6 inches of water on it the back end just might break away if you are driving like a complete idiot - that is the reason given for having best tyres on the rear,  but on modern cars EPS, VSA (vehicle stability assist on Honda) traction control, skid avoidance call it what you like will cut power, selectively  apply brakes to put car back on track when the steering angle sensors and accelerometer sense the car is not following the right track.

As for myself - who does not drive like an idiot am more concerned about straight line braking on a rain soaked motorway where the rear tyres do nothing (about 20% of the grip) and the front tyres do everything including allowing you to steer around the problem by the grace of ABS.   I have always put best tyres on the front and used to do 30K a year until I retired and I never had the back end break away even on very wet roads.   Putting best on rear is an ars3 covering exercise by tyre makers,  just in case someone has built a skid pan on your way home from work.  Try driving on snow or mud with worst tyres on the front.  no one is saying have bald tyres on the back,  they should be of a safe tread depth.

If you want to try VSA in action choose a wet road island preferably with no other traffic around and put your foot down in a lowish gear to provoke a slide,  before you know it the VSA light flashes and the car gently drifts sideways (nothing scary about it) as the brakes and engine management work in harmony to save your sorry a55 and bring it into line. 

[Jocko]

I always put my best tyres on the front. Anytime I have ever experienced a "moment" in a FWD car it has been down to understeer. I have never ever had the back end break away from me. I have been driving FWD vehicles for 40+ years now.

[culzean]

I always put my best tyres on the front. Anytime I have ever experienced a "moment" in a FWD car it has been down to understeer. I have never ever had the back end break away from me. I have been driving FWD vehicles for 40+ years now.

We are agreeing far too often these days 

[sparky Paul]

I always put my best tyres on the front. Anytime I have ever experienced a "moment" in a FWD car it has been down to understeer. I have never ever had the back end break away from me. I have been driving FWD vehicles for 40+ years now.

You probably won't, unless you have to make an emergency lane change at speed, or a sudden sharp wheel input to avoid an oncoming vehicle or other unexpected obstacle.

There is a very simple principle why you should always have the best tyres on the rear, a front wheel skid is much easier to correct and/or control than a rear wheel skid. Once the rear breaks away, you are little more than a passenger... and it's very hairy indeed.

[peteo48]

Not really understanding the physics but the majority of informed opinion does lean to having the best tyres on the back and the reasoning that convinces me is that you do indeed have more control over the front wheels (in a fwd car) than you do over the back where you have no control.

As an ignoramus in these matters I have to go with majority opinion on this - hope I'm not proved wrong but given my cautious driving style maybe I will never be tested in these situations.

[sparky Paul]

On a bend on a flooded road with 6 inches of water on it the back end just might break away if you are driving like a complete idiot - that is the reason given for having best tyres on the rear,  but on modern cars EPS, VSA (vehicle stability assist on Honda) traction control, skid avoidance call it what you like will cut power, selectively  apply brakes to put car back on track when the steering angle sensors and accelerometer sense the car is not following the right track.

That's a complete straw man. This isn't about normal driving, this is about the rare moment when something unexpected happens. If you think traction control or stability control will make it impossible for the rear end to break away at speed with enough sudden steering input, or even from contact by another vehicle, I'm afraid you're deluding yourself.

no one is saying have bald tyres on the back,  they should be of a safe tread depth.

...and I'm not saying have bald tyres on the front either. No one should go into winter with tyres near the limit, that's just foolish.

How does keeping the best tyres on the front work with a FWD car? The fronts will wear much faster, do you then swap them with the good ones off the back? Do you then swap them back when the fronts wear again, and keep swapping them until you have four with low tread?

Personally, I'll stick to the accepted convention and keep the best tyres on the back end.

[babybadger]

I'm using Michelin CrossClimates, they work very well but noisy at speed

[Jocko]

I never rotate my tyres. I replace the tyres when the tread depth gets down to 3 mm and just replace an axle at a time. I probably replace the fronts twice for each time I replace the rears. On the odd occasion I have had to replace all 4 tyres at the one time, but thankfully it is only the odd occasion!