Effects of wheel size

Can anyone tell me what going from a 17" to an 18" wheel will do to the ride and handling of a full size family sedan? Thanks.

If done correctly - same or larger load carrying capacity and about the same tire diameter - changing to a larger rim diameter has the following effect:

  1. Improved dry and wet handling except for hydroplaning
  2. Decreased hydroplaning resistance
  3. Decreased winter traction
  4. Reduced ride comfort
  5. Increased fuel consumption

Please note: The above assumes no change in the basic tire except for the size change.

HOWEVER, you can completely change this by changing the actual tire that is applied. Put another way, there is more change that can be accomplished by changing tires than a small change in the tire size.

I agree with everything CapriRacer says, but I think that in real-world conditions you would have a hard time telling the difference.

The larger tires will cost more to replace, and on a standard sedan offer little, if any benefit. It’s mostly cosmetic.

Personally, I’d stick with the standard size wheel. You can increase (or decrease) traction and handling with tire choice more than with wheel size.

I have to add one thing to CapriRacer’s list.

They will also be much more suspectable to pot hole type damage. That is both the tyres and the wheels may be damaged.

Non OE wheels may not have the same relative tread to pivot point relationship and totally destroy the critical geometry of the suspension resulting in poor handling and often rapid bearing failure.

This makes no sense.

When you buy aftermarket wheels you order/buy them with the same backspacing, so the scrub radius stays the same.

For the average family sedan you get a slightly harsher ride, and slightly better handling near the limits of traction, which most people will never get near in a family sedan. As CapriRacer and others have said, a change in tire make/model can have more effect.

Most of the outrageous wheel/tire purchases are made by people who are clueless what scrub radius is. Those selling the odd tire/wheel combinations seem to have little or no idea what the effects are until faced with an unhappy customer returning to complain. In fact, many who align cars are clueless of the geometry beyond bringing measurements to the specifications on the screen.

www.carbibles.com has an excellent primer on wheels and tires.

Going from 17 to 18 inch wheels will make the car look exactly 1 inch sillier. (-;

Hear! Hear!

I agree completely. It looks cheap, stupid…ghetto. My neighbor just put these silly, huge chrome wheels on his Escalade pickup truck, which is parked out front like a trophy. It looks like a pimp wagon. It lowered everyone’s property value on the street.