I bought some used wheels with a 40 profile rear tire: 245/40/18.
Is there any other downside other than the speedo will be slightly off?

 

Not ideal, but they will be fine

 

1 or 2 mph difference

 

thanks.

 

haha, nice.
i just did the exact same thing...
bought a set of wheels used and they're coming with 225/40/18 up front and 245/40/18 in the rear.
i just figure i'll switch the rears out to 245/35/18 when these wear out.

 

Yay for cheapness.

Will a 40 series tire be more likely to rub the fender as opposed to a 35 series?

My fronts are coming with 245/40s as well, but on a 18x8 +40 wheel, that'll rub for sure, so I'm buying 215/40s for the fronts.

 

Yes, it will be more likely to rub. The difference won't be that much though, so if you have a little clearance you will be fine.

The gearing will be changed as well, it will be like you installed taller gears.

 

Thanks