Tyre spec letters - confused!

[The_Laird]

I hit another effin’ pothole and now have a bulge in one of my tyres. They were all new in June last year and have only done 3,000 miles, so I’m wanting to fit the same type of tyre. The spec on the KwikFit invoice is 255/35R20 Pirelli P Zero 97Y XL JRS. Now, I get all the spec except ‘JRS’. I can find ‘MO’ and ‘AO’ but the only ‘JRS’ I can find isn’t ‘XL’.
So what’s the difference between the JRS, AO and MO suffixes, and would I notice any difference if I fitted an XL AO tyre? :Confused:

[MikkiJayne]

AO is Audi Option, MO is Mercedes Option, JRS I believe is Jaguar option. They are basically different OE versions of the same tyre tweaked to suit the manufacturer's requirements for ride, noise, handling, etc. I would always be sure to run the same version on the same axle as they sometimes have slight variations in tread pattern, sidewall design etc.

Technically the correct tyre for your car would be the AO obviously, but I find the MO are just as good.

If the JRS isn't available in XL then I suspect its OE on something quite small (the coupe thing maybe), where as the AO and MO XL versions will be fitted to big heavy stuff.

[tintin]

I've always treated the manufacturer suffix as "optional", and have never had an issue with any of the tyres I've fitted to either the Audi or the Tesla, but that might just be me being a bit cavalier again, though I agree with MJ about matching on the same axle - XL is the main suffix I worry about, given the weight of the car.

[The_Laird]

It’s strange how much the price differs between the different suffix letters. And how much they’ve gone up in a year!

[steamship]

The following image may be helpful:

http://forum.a8parts.co.uk/attachment.php?attachmentid=23343&stc=1&d=1589831064

[The_Laird]

So why did they fit JLR tyres to my Audi, I wonder?

[MikkiJayne]

Probably what was either on the shelf, or cheapest. They probably don't know or care what those markings actually mean.

[The_Laird]

Just realised that the suffix on mine is JRS, not JLR, and that’s not on Sean’s list. Even more confused now

[briang9]

https://www.camskill.co.uk/

https://www.oponeo.co.uk/?gclid=EAIaIQobChMIsamB7di_6QIV2-7tCh1ItAdDEAAYASAAEgKCqvD_BwE

[steamship]

Just realised that the suffix on mine is JRS, not JLR, and that’s not on Sean’s list. Even more confused now

Sorry for the confusion Jim, but to make it better, here's another set of codes from another website that shows JRS! I even came across a site where they said that J inside a circle was also used for Jaguar. I would suspect that MJs response is the most accurate.

http://forum.a8parts.co.uk/attachment.php?attachmentid=23349&stc=1&d=1589883804

[The_Laird]

Thanks guys. I get it now, but I do wonder if this is all a bit of smoke and mirrors. Is there really a need to make that many variations of every single tyre size? And can anyone tell the difference?

[MikkiJayne]

The tyre manufacturers want the vehicle manufacturers to use their products. The vehicle manufacturers have specific requirements for ride, handling, noise etc and therefore in order get the contract, the tyre manufacturers have to tweak their design accordingly.

Sometimes the differences are very subtle, but other times less so. Mum's Beetle Cabrio takes 225 45 17 - a really common size. When I did some work on it recently I discovered it had Conti SportContact 5 MO on the front and AO on the back (tyre fitters who don't know or care again). One of the front tyres was damaged, but when I looked at them closely I could see not only differences in the sidewall, but also in the tread pattern itself so I specifically sought out an MO tyre to replace the damaged one. When I had the tyres dismounted to refurb the wheels I could definitely feel a difference in the strength of the sidewalls between them - the Audi version was harder. This would be slightly noisier, but would turn-in better. Given that the Beetle is front engined I ended up putting the AO tyres on the front where the weight was, and the MO on the rear, which seemed to suit it because Mum reported back that it drove much nicer afterwards :) Of course that might have been to do with me spending a couple of hundred hours giving it 'the treatment'! It'll get Goodyears next instead of Contis though as the sidewalls are softer again so are quieter and ride much nicer overall.

[The_Laird]

You’re better than Google, Michaela! Thanks again