Tyre Speed Rating - Can I go Lower?

EdGasket

I always thought you had to fit tyres to the speed rating specified by the manufacturer or risk invalidating the insurance even though you can't do more than 70 mph in the UK. However I've just seen this on
http://www.tyresave.co.uk/tyrspeed.html

"However, in the UK, with a national speed limit of 70 mph, it is quite safe and not illegal to fit a tyre with a lower speed rating, provided you do not exceed this reduced rating. The table below shows the maximum speeds applicable to each speed letter."

So although H rated tyres are specified for my car; what are the consequences of fitting a T-rated instead, other than saving money?

anotherbaldrick

To stay within the law you have to fit a tyre suitable for the vehicles top speed capability , not the speed you intend constraining yourself to.

maninthestreet

This site claims it's a beach of Construction and Use regulations:

http://www.tyres-online.co.uk/techinfo/speed.asp

leosayer

Related article here:

http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=72

mchale

OP, as you have stated it would invalidate your insurance if you had not notified them of the change, I would ring your insurance to find out.

shaun_from_Africa

There is no point in notifying the insurance company because as has already been mentioned, what the OP is considering doing is illegal.
If the top speed of the car concerned is 130mph then fitting tyres that are only rated up to 110mph will make them liable to prosecution.

Lum

My understanding is that while it's called a "speed rating" it actually describes more than just the ability of the tyre to handle being driven at 130mph or whatever without overheating.

For example it also describes things like the ability to stand heavy braking on that particular car without overheating.

I could be wrong on this, but it would explain why this is more of a safety issue and why "but I'll never go above 70" isn't a valid reason for going with a lower rating.

bigjl

Lets not forget that winter tyres twnd to be H speed rated.

The speed rating isn't the only consideration you need to consider load index aswell.

I have read a statement from an Insurance co that stated so long as the speed rating is high enough to cover the use the vehicle is put to then it is fine, hence why fitting winter tyres with a lower speed rating than usually fitted.

Personally I don't think there is any saving worthwhile in going for a lower speed rating. Maybe a couple of quid a tyre.

Not worth the hassle if you ask me.

shaun_from_Africa

But would the insurance company back you up if you were involved in an accident and the police decided to prosecute for having tyres fitted which were not of the correct rating?.
I can't imagine there are too many prosecutions like this, but you never know.

EdGasket

Yes, good point about winter tyres which are often not available in the higher speed ratings. So what would insurers rather you have fitted in snow/ice; winter tyres with a lower speed rating or summer tyres with the manufacturers recommended speed rating? From what I have researched, it is not illegal to fit a lower speed rated tyre as some have suggested as in the UK you cannot legally exceed 70mph.
Not much use phoning the insurers, I think they would need to agree in writing that it was OK so in the event of a claim they can't wriggle out of it and deny the conversation ever existed. However I am reluctant to contact my insurers as they would probably get the wrong end of the stick and slap on a 'modification' premium or charge me an 'admin fee' for answering my question lol.
On my particular tyres, 175/65 14, there is a much wider choice in T rating than in H. Saving is around £15 per tyre for a better brand dropping to the T.

shaun_from_Africa

From what I have researched, it is not illegal to fit a lower speed rated tyre as some have suggested as in the UK you cannot legally exceed 70mph.

It doesn't matter what speed you can legally do. The law states that the tyres fitted must be suitable for the maximum speed of the vehicle concerned.

The Motor Vehicles (Approval) Regulations 2001

16. Tyres
6. Each wheel on each axle shall be equipped with a tyre which has a load capacity such that when the axle is loaded to its maximum permitted axle weight, the weight transmitted to the road surface by that tyre does not exceed that load capacity.

7. The speed capability of all tyres fitted shall be not less than the maximum design speed of the vehicle.

http://www.legislation.gov.uk/uksi/2001/25/schedule/3/made