Tyre load ratings...

[Buggermedumplings]

My current tyres are stock Conti CS3's which have a load rating of 95 however looking for new tyres in a 235/35R19 and yet to find any with this rating- Most are a 91. Is this really an issue?

[Peter Jones]

95 is a rating of 690kg per tyre. So a GVM of 2760

91 is 600.- GVM 2400

What does your handbook say? Technically it's illegal to downgrade.

Pete

[Buggermedumplings]

I'm flicking through the manual now however it's fairly generic. Also looking if its mentioned somewhere on the car...

The GVM of the car is 2090kgs so 91 rated tyres 'should' be sufficient...

[Diesel_vert]

Firstly, there is no such thing as a 235/35 R19 tyre with a load rating of 95. It's load index for "standard load" and "extra load" is 87 and 91 respectively, as you have found out.

Secondly, I believe the homologated tyre sizes for the Passat CC are;

235/45 R17 94W
235/40 R18 95Y XL
235/35 R19 91Y XL

So even though the load index is less than 95, I would assume a Passat CC optioned with 19" wheels would come with 235/35 R19 91Y XL tyres wrapped around them.

What you need to do now is to visit a dealer and see if they have any Passat CC's with 19" wheels and see what the load rating is, to confirm my theory. If true, then you shouldn't have any issues fitting them legally.

[Buggermedumplings]

Great info guys, thanks very much.

[brad]

minimum load rating should be stated on the tyre placard on the fuel flap

[Passat CC]

Did you end up finding 95 rated tyres? If so how much? I'm looking to upgrade to 19"

[Diesel_vert]

I was curious on exactly how much an R36 weighed, so I did some research...

                            R36        R36        CC V6
                            Sedan      Wagon      4MOTION

Weight (1)                  1736 kg    1800 kg    1702 kg
Maximum weight              2270 kg    2350 kg    2130 kg
Payload (2)                  609 kg     625 kg     503 kg

Maximum front axle load     1170 kg    1170 kg    1160 kg
Maximum rear axle load      1150 kg    1230 kg    1020 kg


(1) Includes 68 kg driver, 7 kg of luggage, and fuel tank
    filled to 90% capacity as per EU directive 92/21/ECC.

(2) Payload includes 68 kg driver and 7 kg of luggage.


Figures complied from Passat R36 brochure (in German) dated 05/11/2009

Now, for a vehicle weighing more than 1.7 tonnes, a load index of 91 might be deficient, so I did some more research...

Load capacity at various inflation pressures for EXTRA LOAD tyres with a load index of 91

Inflation pressure (bar)   1.9   2.0   2.1   2.2   2.3   2.4   2.5   2.6   2.7   2.8   2.9

Load capacity (kg)         440   455   475   495   510   530   545   565   580   600   615

Okay, so it turns out that 615 kg x 2 = 1230 kg per axle is not deficient (strictly speaking!) but only if the tyre is inflated to 2.9 bar (42 psi). Note that this has nothing to do with the maximum pressure of 3.5 bar (51 psi) that's indicated on the tyre sidewall.

This means that:
A maximum front axle load of 1170 kg would leave a margin of less than 5%.
A maximum rear axle load of 1150 kg (sedan) would leave a margin of less than 7%.
A maximum rear axle load of 1230 kg (wagon) would leave a margin of 0%.

This assumes the owner is vigilant in maintaining the inflation pressure at 2.9 bar (42 psi) and correctly calibrating the TPMS because these margins will only decrease further if the inflation pressure falls, unless the payload is reduced.


So in conclusion, pay careful attention to the tyre placard, never inflate below the recommended inflation pressures, and remember that the maximum load capacity for any XL tyre is only reached at 2.9 bar (42 psi).