Different tyre sizes on same car in Thailand Motor Forum Posted September 3 1 hour ago, andygrr said: No major problem as long as left and right are the same size. But consider this what size spare would you carry. If you needed to fit the spare and run for any distance you would be compromised. Put the larger tyre on the drive wheels, many modern cars are front wheel drive. In many cases the "spare wheel" is a much smaller tyre only to used in an emergercy aand with restrictions on use.