Tire sizes for stock 18's. Need some info for new tires
 

Will 245/40/18 fit the front and will 275/40/18 fit the rear. Did some searchs but didn't get the answer I was looking for. Which is, will these fit the stock rims. What is the width of the stock rims. 8.0 and 8.5????? Thanks for any help.


Dan

I wanted to know this also. I was thinking of replacing the stock tires with 245's all around. maybe 255's ?? I think the stock wheels are 18x8 all around!

your Touring wheels are 18x8 front and rear... a 275 section width tire will not fit.. you need at least 9.5" wide wheel for a tire that wide.

You can go 245/40-18 on the front and 255/40(or 45)-18 on the rear, but that's about all you can fit onto the 8" wide wheels.

Tirerack lists specs for all their tires and one of the specs is the recommended wheel width for the tires you pick. Try them at www.tirerack.com

Hope that helps,

PeteH

How about 255/40/18 all around? is that at all possible?

You want between a 1/2" and 3/4" overall diameter difference from front to rear. Factory set it up that way for a reason. If you vary from this too much (all 4 same size) you will hurt both your abs and traction control systems. Some racers will do this as those functions arent their only concern, but for a daily driver you must stagger your tires. And yes, a 275 is to wide for your stockers.

Thanks guys. You've all been a big help. 225/40/18 and 245/40/18 it is. Don't want to change wheels till I can get the Volks that I want. Got a big arse nail in one of my rears so that was all the reason I needed to get new skin the whole way around. One 245/45/18 and two 225/45/18 RE040's for sale 5K miles.


Thanks, Dan

You're maintaing the front to rear differential, but changing the ODs. Speedo will be off, and the combination will look to small in the wheel wells. Why not stick with the stock sizes, or go to 245/40s in front and 255/45s out back

Lou

if you do 225-40 and 245-40 you have lost almost a full inch in the rear
245-45-18 = 26.68"
245-40-18 = 25.72"

at 65mph your speedo will show 62.66mph. You will also add untrue miles to your odometer ,and obviously change your gearing.

SIZES
 

So 245/40/18 front and 255/45/18 rear will make everything good?

the difference may be excessive...approx 1.2" difference front to rear.

sizes
 

225/45/18 - 25.9
245/45/18 - 26.7
.8 difference front to rear on stockers
245/40/18 - 25.6
255/45/18 - 26.9
.5 difference
new is .3 smaller on front
new is .2 bigger on back
Went from .8 difference to a 1.3 difference
Is this really bad?

Re: sizes
 

actually....
245/40-18 = 25.72
255-45-18 = 27.04

I fixed it. Typed the wrong thing But is this a big problem. I could lose that much with a couple golf bag in the back. I'm just looking for answers not second guessing someone who knows. It's those little voices in my head.

Its not ride height we are concerned with here. Your computer thinks your tires in the front are 25.97F 26.68 Rear...a .71" difference. It takes that .71 or 21.31 revs per minute difference to adjust the anti-lock braking system, or traction control system when need be. The computer can handle slight tolerance differences. Nissan USA asked to 'try' to keep the difference between .5 and .75" just as they have. with the above 245-40-18 and 255-45-18 you have a 1.32" difference which will create havoc for your computer system when you slam on the brakes..or gas. How bad is it? I dont know. I havent been in a 350z under emergency braking in the wet...but I dont think Id want to chance it. Why is it you want to change tire size anyway?

Sizes
 

I just want to get rid of the RE040's. They are sh!t in the cold and they are still sh!t now. I like the Nitto's that I had in the past. Maybe not the best but I liked them. I can't get the exact same size as the RE040's in the Nitto 555. Open to suggestions for the same price range.

Did order the Nitto but can return if I buy different tires from them. Sorry can't offer you any biz at Discount Tire. The small price difference is not worth the mount, balance and getting the tires to the shop.

Are all the people that are getting different wheels and tires and what not screwing up the abs, traction control and all that. Is there speedo wrong?

Dan

225/45s are tough to find. I believe only Bridgestone and Michelin have them. The SO3s and Pilots come in that size. If you use the 245/40s in front (pretty close to the 225/45s in height and pretty common in performance tires) and go with the 255/45's in back, also common (you will want to be wider in back than the front. Your not that much different than stock ODs that you will have a problem - IMHO.

Lou

I replaced my fronts @ 16,000 miles (bald due to wear) with Yokohama AVS ES100, 245/40-18 (actually had them replaced at a Discount Tire a couple blocks from my work). They fit fine and seem to work very well (been to 3 AutoX with them).

My rears are now stock but are bald (20,000 miles) so I've been looking for new sizes.

There's not too much available from Discount Tire in 255/45-18, or 265/40-18 sizes, so I'll stick with 245/45-18 in back (it also helps reduce the understeer).

Unfortunately, I can't seem to find a company that makes both a 245/40-18 as well as a 245/45-18.

I'll probably end up with the Hankook Ventus K104 in the rear.

The Falken GR Beta FK-451 looks pretty good too (and the tread pattern looks pretty close to the Yoks) but they are more than the Hankooks.

Anyone heard anything about either of these tires?

I'll eventually be buying race tires for AutoX and Track Days, and since I commute quite a bit in the Z I'm looking for decent life and cheap price in my street tires.

Thanks and good luck with your tire search GATORZ.

-D'oh!

This is a real PITA
 

I can say that I honestly did not realize the amount of crap we would have to go through just to put tires on our Z. I guess I'm just old and didn't know how much a 1/4 inch could mess with the cars handling and braking. I still find it hard to believe that this is going to be something that I notice in everyday (spirited) driving. I'm going with the 245/40/18 up front and the 255/40/18 rears. I believe everything I've read in this thread but can't make my mind believe that it is going to be that big of a deal. Will my speedo be off that much with a .27 difference in the diameter on the front? A .47 difference front to back from stock...is that really all that bad. Sorry I just can't bring myself to think that the car is going to handle that much worst. Braking, gearing the list goes on. Like I said I hear what you guys are saying but man I just can't get past that small amount causing me any problems.

I'm done,

Dan

my winter tires at 245/50/17 all around. I have had no problem with my ABS or traction control. Both seemed to work perfect. I called nissan and they could not give me a specific reason that 245's all around would not work. Discount tire also told me about the difference in the tire. When I asked why they blamed the computer and ABS. Nissan can't nail down that it would hurt and discount tire blames the computer. I say run what you want as long as it fits. I am going to try 255's all around :D :D :D

245/40/18 and 255/45/18s are available in the following:
Yokohama AVS Sports
Dunlop Sport 9000
Bridgestone Potenza S03
Michelin Pilot Sport
to name a few, don't know why D'oh says they're hard to find???

For 245/45/18s
add: Goodyear Eagle F1 GS-D3 and all those listed above except the Yokohamas.

What's hard to find is the 225/45/18s as I indicated above.

By the way GATORZ, the 40 series tires in the back, if they handle OK, will look funny in those wheel wells.

Lou