Tyre Load Index

[Dicky]

Anyone know what the 370z rear tyre oem index value is, 96 or 100 or other ??

[Ekona]

Makes no difference in terms of replacements, anything in 19" will be fine.

[Dicky]

Well thats what I would have thought but have done some reading which suggests it is important. Must admit I've never considered it in the past but since the tyres are for my daughters car I want to be sure. 

Ive read it can invalidate your insurance (let's face it they look for any reason not to pay out). The Load Index is apparently the maximum weight your tyre can withstand and could cause blow outs or tyre damage if you hit a pot hole or something.

 

Apparently "each tyre must have a load capacity equal to or superior to half the weight borne by the axle on which its mounted". 

I found a table which shows that a 96 load index tyre can carry 610Kg and a 2017 370z spec which indicates a 55/45 weight distribution and a rear curb weight of 

1515 Kg so I assume 45% of this gives 682Kg suggesting that a 96 load index tyre is not safe, or are you supposed to half this which makes it ok....my brain hurts!!

Id appreciate some input from anyone in the tyre game or someone more knowledgable about this subject than I am 

[Ekona]

Each corner can take 610kg, so 1220kg over the rear axle or twice as much as your calculation  two tyres per axle, remember. 

 

You simply can’t buy tyres anymore that aren’t suitable for modern cars unless horrendously modified, like monster trucks. Insurers won’t give a toss about tyres as long as they’re e-marked and not bald. 

Edited April 16, 2018 by Ekona

[Dicky]

Many thanks Ekona 

[Dicky]

Well, typical of me to go round the houses when trying to sort a problem rather than to go straight to the source. 

Having decided on Pirelli PZero's for the rear of my daughters car I found that Kwick Fit online were selling them for £194 with a load index value of 96. This started me off on a bit of a tangent to find out what this meant and was this index suitable for my daughters car. Well after much research ringing Kwick Fit, the local Nissan main dealer, Nissan Customer services, Nissans Nismo branch in Scotland and Pirelli themselves. No one had any idea if the  96 index was suitable nor did they know how to calculate if it would be OK.

By the way Pirelli even suggested that the PZero has only been tested for the Jag XF suggesting that if you fit it they won't be responsible. I said that every tyre shop in the NE and I suspect the country are selling them to any car owner out there, their response , well that's up to them, giving the impression that should anything go wrong  they will stand by our claim that it's only been tested for the Jag? Couldn't believe any of it.

Anyway after all this grief all I needed to do was to look at my daughters car book to find out that 96 is their recommended rating. No wonder my school reports always said " must try harder"

[Ekona]

Or you could’ve listened to me when I told you it makes bugger all difference  

[davey_83]

Lesson learned hopefully........