Tires: Tire load, passenger car tires, alloy wheels

Question
hi,
I have a VW Transporter. It currently has fitted 195 70 R 15 104 102 tyres. I have a set of 18" alloy wheels to fit to the van. I am looking at 235 40 18 tyres.

My question is: would the change of tire size affect the load rating I should look for?

The van is used for personal use only (no rubble etc carried).

Thanks

Answer
Peter,

No - but with one qualification.  You need to find tires with at least a 104 load index - and here's the one exception.

The tires you currently have are designed for "Commercial" use.  That's why there is a "C" after the tire size.  These are the European equivalent to "LT" tires.

But if you plan to use tires that are designed for passenger car use, you need to adjust the load index upwards.  The clues that the tires are designed for passenger car use are the letter "P" in front of the tire size or the use of the terms "Standard Load" or "Extra Load".  

Another clue would be the maximum pressure printed on the sidewall (or listed in the specs).  Tires designed for passenger car use will have maximum pressures of either 35, 36, 41, 44, or 51.  If the maximum  pressure is listed as 50 then it could be either, but a maximum pressure above 51 is definitely a "C" type or an "LT" type.

So if you are going to use passenger type tires, the the load index has to go up to 108.

Also if you plan to use passenger car tires, the pressure specification needs to be adjusted.

BTW, you should check your vehicle placard on the doorpost.  It will list the original tire size and the proper pressure for that size.