Tyres - cracked tread blocks

[dash]

Just passed another MOT - hurray !!

Our iQ2 has covered only 15,000 miles since new and is still on the original Bridgestone Ecopia tyres.

We have been getting advisories on cracked tread blocks. Is this unusual, or is it typical of tyres which have suffered years of ozone exposure? I know rubber can crack with age but I've never come across tyres doing this before and wondered if it was specific to Bridgestones.

Front tyres are now reaching the legal minimum tread depth.

Any recommendations for replacements (preferably quiet with good grip in all conditions)?

  Dave

[FROSTYBALLS]

Cracked tread blocks aren't just specific to Bridgestones - any make of tyre can suffer with this. Usually sidewall or tread block cracking can begin at any time from around 4 years onwards - all to do with ageing.

T speed rated tyres seem more common for your size of tyre. Bear in mind the noise rating for the EU tyre labelling is a measurement of external noise, which may not relate directly to noise heard from inside the car.

[sparrow2]

My 59 plate  IQ3 has done 52,000 miles. I have had the front tyres replaced twice but I am still on the original rear ones. I inspected them closely and saw some small cracks in the tread and sidewall. I took them to the garage for an inspection and they told me they were OK at the moment - the cracks were too small to worry about.

Ideally you should rotate the tyres and it is mentioned in the owner's manual. Then the rear ones would never get to six years old. However when I mentioned this to the garage, when it was about a year old, I was told they never bothered to do that. I can see their point. Rotating will prolong the life of the tyres but it takes time and effort. The question is whether the cost of the effort is less than the amount you save by rotating the tyres?

 

[FROSTYBALLS]

Rotating tyres evens out the wear, but in the UK it no longer seems to be recognised as good practice - http://www.abbeytyres.co.uk/tyre_rotation.html

https://www.kwik-fit.com/tyres/information/tyre-rotation

[mickburkesnr]

I find the Kwit Fit site odd. They don't recommend tyre rotation but recommend your best tyres are at the rear of the car? For most people with FWD cars they'll be replacing their front tyres, so with the above they'll be moving them to the back of the car, even though that's a tyre rotation that they don't recommend? Or have I misread the whole thing?

I've seen videos where they fit new tyres to the front of the car and to the rear of the car, and when you fit them on the rear they do handle much better than putting them on the front. Personally I've tried both, rotation and not rotating and I prefer rotating them as they do even out the wear. Plus it removes the possibility that I'm going to be running older rubber on the car that's more likely to crack than new tyres.

[FROSTYBALLS]

Tyre manufacturers have for a number of years recommended that, if just renewing a pair of tyres, these are fitted to the rear - whether the vehicle is front or rear wheel drive. Going back to 1998, when I wanted two new tyres for my Corolla, my local Costco had a policy of rigidly following Michelin guidance and rotating used tyres to the front/fitting new tyres only to the rear, despite this costing them time/money. They declined to fit tyres where the customer wanted tyres fitted contrary to this guidance.

[craggle]

I change my wheels each year for winter tyres. I have the winter tyres on the original Toyota wheels and have 17" OZ Racing wheels with the summer tyres on them.

I always mark the tyres as they come off with an F or an R so I know where to fit them next time. The tyres on the front of the car this year will be on the back next year. This evens out the wear and makes them the same time so when they need replacing they all will be replaced. I can only move my tyres front to back though as they are all directional tread pattern so can't swap them side to side.
I can't see how rotating your tyres can be bad practice if it's done regularly. 

 

Craig.

[sparrow2]

I double checked my owner's manual. Toyota do recommend rotation. Look in the index for "Tires - Tire Rotation". However when I phoned the garage about the matter at the suggested number of miles they did not seem too interested.

I think it comes down to cost. If, as in Craig's case, you are taking them off anyway you are bound to save money by rotating the tyres because they will last longer and you are not spending any extra work doing the rotation. If, on the other hand, you rotate them specially you will make them last longer but the question you need to ask is "Is the cost of the effort of rotating the tyres less than the extra amount you need to pay for replacing the tyres sooner?"

 

[Soeley]

The reason for fitting new tyres to the rear is to prevent the back end kicking out and loosing control in the event of aquaplaning.

[FROSTYBALLS]

3 hours ago, sparrow2 said:

I double checked my owner's manual. Toyota do recommend rotation. Look in the index for "Tires - Tire Rotation".

I've no doubt the owners manual does recommend tyre rotation - but, how old is your owners manual? If you have an early IQ the manual could be the best part of 7-8 years old, and things can change tomorrow, let alone within the past 7-8 years.

[Hairy Nugget]

While the science for not rotating it is sane, the IQ has like 65/35 weight distribution. If there was ever a car where rotation would make sense, it would be on the IQ.

I have tested myself with the stock ecopias in the back and nokian hakkapeliittas up front on snow just for fun in a closed area. And even then I had to provoke it really hard to get any oversteer (yes, with ESP turned off). Not that I recommend such a setup..

Unless you are planning on going to the Nürburgring or some other track with wild elevation changes to practice extremely late braking liftoff, slightly more worn rear tires will NOT cause oversteer on the IQ.