Planning on buying new tires for the g37 and was wondering if I can use a 225/40/19 instead of a 225/45/19 tire size in the front. There shouldn't be any fitment or TPMS problems for the car right?

 

By going to a 40 series your reducing the overall radius and circumference of
the tire... Causes your speedo to be off by roughly 2mph... I'd not want to
put even less sidewall height on the wheels either, you're losing about .5"

If you want the 40 series... Goto the 245/40/19. That keeps everything in
check per stock configuration. Is it a particular tire you're looking at in that
size that is driving this decision?

 

x2... run the 245/40/19 in the front and 275/30/19 in the rear. It fits perfectly fine (many members run this as well as myself), it's actually more accurate for a speedo reading than the factory setup, and you get a meaner looking ***-end for your G. Oh and it's much easier (and cheaper!) to find tires in those sizes rather than the factory sizes :P

 

I am looking for all season tires that will get me through the winter and the Continental Extreme Contact DWS seem to have the best rating when it comes to snow conditions. The closest size to the factory setup for the front tires is the 225/40/19 for the continental's.


So my speedometer will be inaccurate? I contacted some tire stores and they said these would fit fine. I don't think I want to go for wheels wider than the factory either cuz they seem to be more expensive when it comes to the continental's at least. Any input is appreciated.

Here's the link to the tires. (Continental ExtremeContact DWS)

 

friend just got the dws on their lexus. awesome looking tread and handle pretty well. treadwear is pretty long too. i dont think the speedo being off by few mph is a big deal.

 

But will it be off? Why is it that the speedometer is off? Will it overestimate or underestimate the actual speed?

 

+1 on 225/45-19. 40's about an inch shorter than what should be installed.