Alternate tire size = fail inspection??!!??, State of Maine Options

[BCinSC]

Sorry: NPC - '95 Lexus ES300, but I know y'all will give excellent advice

Want to put 195/65 R15 on instead of 205/65 R15 and am told that car will fail Maine inspection because it has anti-lock brakes and those 12mm in circumference difference will negate effectiveness?

[groot]

QUOTE (Pnambic @ Dec 9 2005, 12:05 PM)

Also, while it is true that the cars are tested extensively on the tires they leave the factory with, I would be very surprised if the tire choice is not heavily influenced by whatever deal the tire manufacturers are willing to cut the car manufacturer. I'm sure they have an idea of what class tire they want, and then find a good deal on a tire in that class. There are lots of ratings for tires (noise/load/speed/weather/etc) to take into consideration when selecting a new set, but I don't at all feel obligated by loyalty or safety to stick with the OEM tires.

While this is true, it's a bit more complicated than that. See, the tire manufacturers make deals with the OEMs, and submit up to 10 different tires for the OEMs to test. And they're always a compromise. While tires can be built to focus on different attributes, you really can only get 2 of those attributes since the attributes work against each other (fuel economy and NVH, or snow and wet handling, steering precision and NVH, etc). So, you look for the best mix and tune around the tire.

Picking a tire with slightly more grip on a passenger car can lead to a debead or rim strike in an emergency situation. We tested a competitive vehicle last week that debeaded it's right rear tire during the tire warm-up session. Scary stuff. So, the point is not all OEMs are as thorough as we are.