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Does wheel choice make a difference in ground clearance?

Does wheel choice make a difference in ground clearance?

The specs on the Model 3 indicate a 5.5" ground clearance. My wife and I had planned for the Aero wheels (we actually like 'em a lot, especially with the Midnight Silver body color!), but are working with a very short, relatively steep driveway. Initial measurements have it veeeery close to scraping the bottom as the front wheels begin descending that driveway, so we're looking to eke out as much clearance as we can.

Does anyone know whether the sport wheels, with their extra inch of diameter, would add to the car's overall clearance? Alternatively, can the coil suspension be adjusted so the car rides a little higher?

ReD eXiLe ms us | 2017年8月30日

The outside diameter of the tires should be approximately the same in a proper wheel application. The 18" and 19" OEM applications probably meet that parameter. The 'clearance' for the wheels themselves may become an issue with the larger size in an area replete with potholes.

eeb9 | 2017年8月30日

ReD is correct - the wheel size does not change the overall diameter of the tire. You make up the difference by having a shorter sidewall. This is fine if you have relatively good roads in your area.

Potholes are deadly to short sidewall/large rim combos, and there's not enough sidewall to absorb the impact. If you have a lot of potholes in your area, consider this in your decision.

eeb9 | 2017年8月30日

ReD is correct - the wheel size does not change the overall diameter of the tire. You make up the difference by having a shorter sidewall. This is fine if you have relatively good roads in your area.

Potholes are deadly to short sidewall/large rim combos, and there's not enough sidewall to absorb the impact. If you have a lot of potholes in your area, consider this in your decision.

hiimphilll | 2017年8月30日

the 18" aero wheels use a 235/45/18 michelin mxm4 tire with an over all diameter of 26.3"
the 19" sport wheels use a 235/40/19 continental procontact tire with overall diameter of 26.4"
0.05" more ground clearance with the 19". virtually no difference.

You may just have to change your approach angle a bit as you come up to your driveway, that usually helps. if not.. another thing is possibly going to a different tire to gain some height in the future, 245/45/18 for instance, will gain you 0.2" additional ground clearance.

Trevoroklein | 2017年8月30日

Perfect -- just the info I was looking for. Thanks to all three of you!

Xerogas | 2017年8月30日

Could someone explain this to me? If the tire is .2" larger in diameter, wouldn't that mess up the car's odometer? Fewer rotations per mile means the car 'thinks' it's driven fewer miles. Or does the mechanic input some number into the car's ODB port to make up for the mileage calculations?

Bighorn | 2017年8月30日

No

Carl Thompson | 2017年8月30日

@Xerogas:
"Could someone explain this to me? If the tire is .2" larger in diameter, wouldn't that mess up the car's odometer? Fewer rotations per mile means the car 'thinks' it's driven fewer miles."

The two tires are less than 0.1" different in diameter.

Diameter:
235/45/18 = 26.327 inches
235/40/19 = 26.402 inches

The circumference is what matters when going from rotations to distance, though:

Circumference:
235/45/18 = 82.709 inches
235/40/19 = 82.945 inches

So the difference in circumference is 0.236 inches.

That difference is much less than one half of one percent so that's how much your speedometer will be off. Since your speedometer isn't accurate to that degree anyway there is no measurable difference.

Carl

Carl Thompson | 2017年8月30日

Of course over the course of 100k miles that could still mean a difference of a few hundred miles total which might sound like a lot to some (but it really isn't). But remember you'd get a much bigger difference just from tread wear (new tire vs. bald tire)!

Carl

ReD eXiLe ms us | 2017年8月30日

Bighorn is always right.