Hey Guys,
I am planning to replace tires with 265/50/20 but I cant estimate pros and cons, I just like the wild view of big tires like Infiniti FX series. Did anyone try it before? any comments welcome please advice.....
Thanks

 

I'd expect you'll get a somewhat rougher ride, possibly lower MPG.

You might want to drive an FX to see if that's really the ride quality you want.

 

Personally I think 265/50/20 has too tall a side wall (50). I run 255/50/20 on my RX330 and it is already oversized compared to stock in over all diamter. Also, I'm not sure how the RX400H rear struts are, but if they are the same as the non hybrid RX330/350 I'm willing to bet the tire will be too tall and hit the rear struts lower perch mount. As it is, my set up has less than 1/8" clearance. Also, what offset and width are your 20" rims? You might run into inner fender well clearnace in the rear, as I have about 1/2" clearance and I'm on 20X8.5" +20 offset.

 

Though it does depend on the weight and size of the rims and tires, in most of the cases in upsizing you have more unsprung weight and will lose acceleration. However, you have to factor in what you want in terms of look and feel, too.

 

What should you expect with the oversize tires?
1) Rougher ride
2) Slower acceleration
3) Poored fuel economy
4) Errors in speedometer

With all the computer involvement in the hybrid system, you might even run into some problems with with the operation of that system.

I drove the FX45 prior to selecting the RX400h. My other car is a G35 coupe and I really like the Infiniti dealer but the ride was so stiff I could not imagine taking a long trip in the FX.

If looks are your only criteria, you bought the wrong vehicle.
Steve

 

LOL! That's about the best summary I've ever heard about the RX's appearance! We love ours as is, not pretty but a practical and comfy ride.

It's very, very easy to screw up a good thing by changing tire size, especially in rolling circumference. Ordinary transmissions can be completely buggered by a change in tire type (shift points vs engine torque), can't imagine what kind of trouble it could cause in a hybrid.

 

Ok Guys I got the point... please tell me what is the appropriate bigggest size rims and tires? do you think 20 or 19 inch rims are OK?

 

Don't forget also that ABS and dynamic vehicle stability systems etc are probably calibrated to a particular wheel diameter as well....

 

I tried with bigger/wider 18" wheels already.

Don't like the feeling of it, so I returned the tires. Maybe 20"+wider wheels and tires will improve.

edit: Mine is actually lowereds with TTE springs. A bit harder on the ride but reduce a lot of bodyroll movements!

 

That will not be a problem at all because the calculation is done by proportional.

 

Yes and I agree with 1,2,3,4.
Plus, master cylinder carries more load and brake pads/rotors wear out faster.

No, you will not mess up anything else if same diameter size tires are used for front and rear.

 

With this type of vehicle, alot depends on how much you want to sacrefice to achieve the "look". I live in pothole heaven, and as an everyday vehicle too big a compromise for me. I would not want to go 20" rims. To maintain the overall diameter you would need to sacrefice the sidewall width too much imho. And I hate have the vehicle running out of spec due to wrong rolling diameter. Good luck with your choice.

I saw a plus 0 setting available on the discount tire website...

255 / 55 - 18

I know the recommended size for the rim width is 8", but I really like the "Factory Rim" look. I wonder if anybody has photos of this setup on the board...

sorry, my 0.02 worth.