Car tyre load index?
 

Hi gurus :) I got a really nice Special for winter tires for my car but after I bought them I realized that the load index was a bit lower than what I used to have before ... can I not carry my girlfriend anymore??? :/

The gross weight or Gesamtgewicht of my car is 2385kg as written in my car papers. The tires I got have load index:
- front 94V (max 670kg per tyre)
- back 96V (max 710kg per tyre)

Doing the math these tyres support up to 2760kg, and almost 400kg more than the gross car weight; which should be enough to accommodate for 4 passengers and luggage.

I called a garage and they said it wasn’t right, that I needed 98V front and 100V back. Then I called the technical branch of the strassenverkersamt and they confirmed it was OK. However, I was left wondering whether my reasoning for calculating whether it works or not was flawed e.g. if I get one flat tyre do the others have to be able to support the whole car?

Any hints appreciated.

Re: Car tyre load index?
 

You don't normally need to do this calculation, it should be on the tyre information label on the car (often on the driver side pillar when you open the door). Or maybe in the car manual.

I'm not sure but it probably isn't even relevant to do the calculation - the insurance will say you must follow what the manufacturer says.

Re: Car tyre load index?
 

Get a new, 'lighter', girlfriend?

Re: Car tyre load index?
 

You will never drive on 3 so it's irrelevant, even with a burst tire the weight will go via the rims to the road.
I assume thats the max weight including passengers & luggage, you claim car not tank.

Re: Car tyre load index?
 

Not necessarily.

https://thumbs.gfycat.com/Altruistic...Flyingfox.webp

Re: Car tyre load index?
 

Don't fill the gas tank. ;)
Can also remove the rear seats to compensate for you GF.

Re: Car tyre load index?
 

As you checked with the StVA/SAN, and I assumed you stated No. 18 Stammnummer or No. 24 TG-Number, it is what is stated in the cars CoC and is what the manufacturer has considered as good enough.

Here a little exercise for you: Try to find this information for your car. Have fun if it is not US import.

The information is normally only found on the cars CoC. In EU countries it is often also mentioned on the cars registration paper. In Switzerland unfortunatly not. If you do not find you can get an extract from the Swiss type apporval database TRAGA which is available from your local garage, tire dealer or StVA/SAN. See example here: https://www.targatyre.ch/

Re: Car tyre load index?
 

It's possible my Swiss registered Ford is an outlier, but it definitely shows the full tyre specification on the driver information label for a range of options - wheel size, width, profile, maximum weight and speed rating.

Re: Car tyre load index?
 

You can also go the easy way: find your car on Reifendirekt. It provides compatible tyre sizes including load index.

Re: Car tyre load index?
 

The higher rated tyres are stronger and generally therefore corner and brake better than the lower rated tyres. You'll often see "XL/ extra load" tyres specified for high performance cars and in that regard it has less to do with their weight.
Dunno about the Swiss rules but generally it's ok to go higher but not lower.


Your calculation in itself (i.e. ignoring any other rules) seems reasonable to me but the "other rules" might dictate a certain minimum rating.


If that 2385kg is the kerb weight then that's a monster of a car and I'd have thought the load index would be up in the 100s. I'd recommend you check with the car's papers. It could be that it would be legal but you might end up with a crappy driving experience.


Edit: seems "Gesamtgewicht" means allowable maximum weight i.e. with passengers and luggage etc. so not quite the monster I thought it was but probably still 5-series size.

Re: Car tyre load index?
 

Why not do the same as everyone else - look at the ones currently on the car!

Re: Car tyre load index?
 

Well you never know if some :eek: has put the wrong ones on! Plus it's surely easier to google than to go out to the car. :-)

Re: Car tyre load index?
 

So does my car.

Re: Car tyre load index?
 

A fair point, and indeed Google does pull up the following table for my car from the manufacturer's UK site:

215/60 R16 99V
225/50 R17 98W
235/55 R17 103W
235/50 R18 101W

Which is identical to the label stuck to the B pillar.

It also shows UK main dealer prices for the tyres, which is very depressing when even Reifendirect cost more in CH.

Re: Car tyre load index?
 

This thread got me thinking and doing some digging.
As mention previously, just like newtoswitz's car, my car too has a huge range of options and allows different combinations of tyre specs. In fact, in my case, where the car has a different set of wheels in the front vs. the rear, the load indices are ( therefore ) different for the front vs. the rear. So very clearly, it's not that there is one load index that is sacrosanct for a car. It's both the tyre dimensions/ specs and the car that seem to determine the load index.
Can't figure out why changing the diameter / width / aspect ratio should change the load index. And can one take the lowest load index as the minimum to stick to?
Sorry for turning this into a purely academic discussion.
P.S. These Transportation/ driving threads are always so interesting.

Re: Car tyre load index?
 

If the type approval/car sticker lists more than one dimension than the load and speed index must be at least the one given for a particular dimension.

Art. 58 VTS https://www.admin.ch/opc/de/classifi...index.html#a58

Except for winter tires where you can as low as 160 km/h (Q). But no exception with put further exception: In Italy during the summer months the speed index a winter tire must be at least the one given in the type approval/car sticker.
Art. 59 VTS https://www.admin.ch/opc/de/classifi...index.html#a58 and some dirctive or circulary from the Italien tranport ministry, http://www.pneumaticisottocontrollo....gory.php?id=15

Re: Car tyre load index?
 

Not for any length of time, if you do an emergency stop, multiples of the weight limit will be on the front tyres for several seconds, same if you hit a pothole.

Re: Car tyre load index?
 

Thank you for the thoughtful comment! Indeed spot on, my car is a 530d xdrive.

Re: Car tyre load index?
 

Thank you all for the thoughtful and helpful comments. Indeed I have a 530d xdrive G30 limousine (or coupe).


My current summer tyres are:
- 245/40 R19 98Y front (extra load) Pirelli

- 275/35 R19 100Y back (extra load) Pirelli


I'm attempting to mount for Winter (got them second hand with profile of almost 7mm for 270.-CHF :msnblush: they look new):
- 245/40 R19 94V front Pirelli sottozero 3

- 275/35 R19 96V back Pirelli sottozero 3



To check for validity I did the following:

• I called technischer verkehrsamt zürich 0588113228 and they checked my car data and confirmed it was OK
• I checked on the door side and the minimum load index is indeed listed 94 or 96 BUT for different tyre sizes .. so I assume it's ok.
• I called Binelli AG and they were confused and didn't know which tyre load index spec is the minimum, they said it was safer to put the highest and most expensive one ... how surprising.
• I then contacted BMW directly, and they confirmed that for my car given the series, plate number and VIN serial number "the 94V and 96V are approved".
• reifendirekt.ch doesn't list these indexes as available for my model but other online tyre sellers do.
• pneuexperten.ch lists V94 for front and V96 for back see here https://www.pneuexperte.ch/de/TyreVe...eSeason=winter

I also find sellers in Canada / UK listing 94 and 96 as valid load indexes for my car ... so that's all the research :msnsarcastic:

Re: Car tyre load index?
 

Beware of using the online tyre retailers as a source of information. Often when you put in your car details it will then simply find the tyre size and give you all tyres that they have in that size whether they're suitable or not.