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· Registered
187 Posts
Discussion Starter · #1 ·
For those that have checked, there are not many options in the factory size of 235/45/19... I hadn't made my mind up on run-flats or not, but I think I wanted to switch over to Continentals (they have no run-flats in that size.) Two I was considering in this size are ContiProContact or ProContact GX

Has anyone changed to 245/40/19? The options are so much greater.
I really wanted ExtremeContact™ DWS06 in the OEM size, but it is offered at this alternate size that still fits our 19x8 rims. Probably will have my speedometer off about 1 mph or so.
Also really considering ControlContact ™Sport SRS, SureContact™ RX or ControlContact Sport™ A/S (discount tire only)

Has anyone gone from 235/45s to 245/40s?


· Super Moderator
665 Posts
Ignoring brand differences, a 235/50/18 and 235/45/19 have the nearly the exact same diameter (27.3") so the speedometer would reflect the same speed and odometer would reflect the same mileage.

Going to a 240/40/19 would have a diameter of 26.6" (-2.6%) and your speedometer/odometer would read slightly fast (and odometer would accumulate slightly more miles than you actually traveled). When your speedometer indicated 70mph you'd actually be traveling 68.2 mph.
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