Alternative tyre sizes

[bobsy852]

Anyone know if I can put different sized tyres on my wheels?
My fronts are getting low. I've ordered some replacement "summer" tyres to match and I'm happy to fit those.

However, I visited my parents this weekend and my dad explained that he has some new winter tyres lying around from a car he used to own, and with the winter weather no doubt soon approaching it might be worth using them if I could.

Problem is, the sizes don't exactly match.

So my current tyres are 225/50/R17

The winter tyres I've been offered are 245/45/R17

Could these be fitted and be safe to do so?

Thanks

[wimorrison]

Here you go

https://tiresize.com/tyre-size-calculator/

[baggy798]

Everything will be fine as long as your rimps are 8" wide.

[bobsy852]

Thanks! Daft question, how do I find out how wide the rims are?

[60041]

The wheel size is normally marked on the back of one of the spokes on an alloy wheel, or stamped around the centre boss on a steel wheel. The width is measured in inches and is followed by the letter J

[Billggski]

225 if they are the originals, normally sit on 7j, 245 on 8j.
You may consider picking up some 8j alloys.

http://www.wheel-size.com/size/volvo/v70/2009/

[skyship007]

Originally Posted by bobsy852

Anyone know if I can put different sized tyres on my wheels?
My fronts are getting low. I've ordered some replacement "summer" tyres to match and I'm happy to fit those.
However, I visited my parents this weekend and my dad explained that he has some new winter tyres lying around from a car he used to own, and with the winter weather no doubt soon approaching it might be worth using them if I could.
Problem is, the sizes don't exactly match.
So my current tyres are 225/50/R17
The winter tyres I've been offered are 245/45/R17
Could these be fitted and be safe to do so?
Thanks

In most of the EU, the cars papers have the approved tyre size alternatives listed, just as it is in the handbook and it is illegal to fit tyres that are not listed.

Your owners handbook will list alternative tyre sizes that do not effect the safety of the vehicle or handling qualities.

If you fit tyres that are not listed then you have modified the vehicle in terms of its performance. If you fit the non OEM approved tyres yourself, then it should be
declared as a performance modification to the insurance company.

In a serious crash, an accident investigator will check the tyres and if they are not OEM spec, that can be used to partly invalidate the insurance policy, or to blame you for causing an accident which was not your fault. They will pay for 3rd party claims only, on the grounds that the vehicle was not described in the application correctly, or gross negligence.

If a garage fits the tyres and wheels to your car, then keep a full receipt, as they are now responsible for partially invalidating the insurance. Oddly enough the EU regs were never enforced in the UK as regards non OEM list tyres, so the insurance folks are less inclined to use the non OEM standard excuse, but still use the gross negligence part when they think the onwardsman will accept the wrong tyre size a significant factor in the cause of an accident.

[DAN AT ADRIAN FLUX]

Hi,
If you do find you have any issues with insurance at all then please feel free to drop me a line.
Regards,
Dan.

[tt82]

Originally Posted by skyship007

In most of the EU, the cars papers have the approved tyre size alternatives listed, just as it is in the handbook and it is illegal to fit tyres that are not listed.

Your owners handbook will list alternative tyre sizes that do not effect the safety of the vehicle or handling qualities.

If you fit tyres that are not listed then you have modified the vehicle in terms of its performance. If you fit the non OEM approved tyres yourself, then it should be
declared as a performance modification to the insurance company.

In a serious crash, an accident investigator will check the tyres and if they are not OEM spec, that can be used to partly invalidate the insurance policy, or to blame you for causing an accident which was not your fault. They will pay for 3rd party claims only, on the grounds that the vehicle was not described in the application correctly, or gross negligence.

If a garage fits the tyres and wheels to your car, then keep a full receipt, as they are now responsible for partially invalidating the insurance. Oddly enough the EU regs were never enforced in the UK as regards non OEM list tyres, so the insurance folks are less inclined to use the non OEM standard excuse, but still use the gross negligence part when they think the onwardsman will accept the wrong tyre size a significant factor in the cause of an accident.

Sorry but I disagree.

I've never known an insurance assessor to check a tyre size yet and I imagine they would only go into that much detail in claims costing more than 6 figures or where the crash happened as part of a criminal act (drink driving etc).

Pretty much every car has the option of a space saver spare tyre. These are generally a different size to the standard fit tyres but are legal. Whilst they may be speed limited, there is nothing to say I can't plow into a tight right hand corner at 50mph with a space saver fitted on the near side front wheel. Should I crash, do I have claim against the car manufacturer as they have provided me with a road legal tyre that is drastically different in size to the other 3 tyres, including having a smaller rolling radius, which as you say, will "effect the safety of the vehicle or handling qualities."

Common sense is the approach here. As long as the tyre is an appropriate size for the rim it is mounted to, it does not foul the body work and would pass an MOT then it is fine. Fitting a set of premium tyres which are slightly different in size as to what is in the handbook is going to have far less effect then fitting completely legal cheap Chinese budget tyres.

If I ever were in a position that I had a claim voided for this reason, I would ask that the insurance company prove their claim buy doing a controlled test of the tyres and comparing this to a range of standard fitment tyres from the market, ranging from budget to premium.

[Simon Jones]

Originally Posted by tt82

As long as the tyre is an appropriate size for the rim it is mounted to, it does not foul the body work and would pass an MOT then it is fine.

Two points to bear in mind: running full size tyres of different size on the same axle is an MOT failure, as is presenting a vehicle for test with a space saver fitted.