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Discussion Starter · #1 ·
Just wanted to ask a quick question regarding the need for fitting tyres with the Extra Load stamp, is it necessary? I'm not entirely sure about the purpose of the XL rating as they still have the same load rating (92) which is 630kg per corner. I ask because I've found some part worn winter tyres, but they don't have the extra load rating but otherwise match the spec found here under the R performance section.
 

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Hi, as far as I am aware there is no need for the XL tyres. I doubt if they where on the shelf when the tyre spec's for the X type where being formulated. However that said I have had them fitted to both my car's over the past few years. I think it gives a very slightly harder ride but that could well be my imagination. To my completely unscientific thinking I don't see a problem with stronger (firmer) sidewalls.
 

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Discussion Starter · #3 ·
Hi, as far as I am aware there is no need for the XL tyres. I doubt if they where on the shelf when the tyre spec's for the X type where being formulated. However that said I have had them fitted to both my car's over the past few years. I think it gives a very slightly harder ride but that could well be my imagination. To my completely unscientific thinking I don't see a problem with stronger (firmer) sidewalls.
Thanks for the reply, that was my presumption. I don't want to buy them and end up finding that I shouldn't really have them fitted even if it will only be for around 1000 mile over the winter months. I may well just hold off until another set comes up for sale with the XL rating to be sure unless others have an opinion.
 

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As your linked info recommends, the 18" size needs to be an XL tyre. The smaller ones don't.

By being stronger, XL tyres can be run at higher pressures increasing the load rating further still. This strength usually comes at the expense of weight and often stiffness. If you don't need the XL type, the standard tyre will probably perform better as the compromises are different, should be naturally better. If you need them, i.e., the manufacturer specs them, the reinforced tyre is required to take the weight or cope with the heating effects of maximum speed, etc. Even if you in the UK should never get near these limits, it is still what should be fitted to remain at or above the design spec.

The unknown is that maybe when the car was designed/handbook was written, there was only an XL model in that size and later a lighter tyre came along. However, without more info, dropping to a standard tyre wouldn't be advisable.
 

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Discussion Starter · #5 ·
As your linked info recommends, the 18" size needs to be an XL tyre. The smaller ones don't.

By being stronger, XL tyres can be run at higher pressures increasing the load rating further still. This strength usually comes at the expense of weight and often stiffness. If you don't need the XL type, the standard tyre will probably perform better as the compromises are different, should be naturally better. If you need them, i.e., the manufacturer specs them, the reinforced tyre is required to take the weight or cope with the heating effects of maximum speed, etc. Even if you in the UK should never get near these limits, it is still what should be fitted to remain at or above the design spec.

The unknown is that maybe when the car was designed/handbook was written, there was only an XL model in that size and later a lighter tyre came along. However, without more info, dropping to a standard tyre wouldn't be advisable.
Many thanks for the detailed explanation Neil, that clears it up for me. I'll hold off and get some XL rated tyres, should also be better suited for winter tyres as they'll take more punishment with unseen potholes and such. You're very much the tyre guru :)
 
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