tire rack says minimum width is 8 inch for 245/40/18 tires.......
local tire dealer/installer says it's ok to mount on them on 7.5 width rims......anyone out there running them on 7.5? inputs please.......thanks.


04 6mt Sedan / stock airbox mod / z-tube / k&n panel filter / crank pulley / 18" r/h c2s / s-tein springs

 

i was also told minimum 8" width with my 245/45/18 tires, so i got 18x8s. i think with anything smaller, the tires will curve inward...leading to poor tread wear. plus, it might not look nice.

2003 G35 Sedan 5AT
{Z-Tube} {JWT_POP_Chrgr.} {V1} {21%_Tint} {Matte_Race_Pdls} {Blck_w/Grpht_Lthr} {Prm_Pkg.} {Sprt_Tuned} {Wntr-Sprt} {Nav.} {Xenon} {Sunroof} {Aero-Body_Kit_w/Spoiler} {Trunk_Mat}

 

I'm running my 245s on 8.5"
It gives a nice square side wall.

IMO 7.5 is too narrow, if you pinch the sidewall in too much you
will alter the tread profile. In this case a 235 size would actualy out perform the 245 tire.


<font color=blue>________________
04 Silverstone G35, 5AT, Prem, Aero
ES100 225/45-18 front 245/40-18 rear
Painted calipers, side marker signals
Debadged INFINITI</font color=blue>

 

Why on earth would you let a mechanic convince you to go against a manufacturers recommendation? Some automobile manufacturers produce vehicles on them with tires that exceed the recommended width, but they have done this in collaboration with the tire manufacturer. I wouldn't put any tire on any wheel without a blessing from the tire manufacturer, whether you know someone that did it or not isn't relevant when you're talking about such a critical safety and performance item.

Each tire has different specs. Check other tire brands to see if they are compatible with the wheels and choose one that fits.

At 80 (or greater) MPH with the only thing keeping you from departing the ground being the tires, I for one would feel uncomfortable wondering who was right...the Michelin engineers, or a guy named Buddy at the Gateway Tires R Us store.

2004.5 Coupe/5AT/Ivory/Everything but front spoiler/Nismo CAI/Crawford V5

 

tire safety engineer or buddy the installer down at the local tire store.........no brainer. thanks for the inputs fellas.


04 6mt Sedan / stock airbox mod / z-tube / k&n panel filter / crank pulley / 18" r/h c2s / s-tein springs

 

2004 Maxima's run 18x7.5" with 245/45-18"

As a general rule you do want to maintain rim width to tread width width, however, were only talking about being 1/2" under and these are rims you've already bought and paid for I'd think. I'm running 255/40-18 on 8" in the rear, I don't like the idea at all I'd rather have 9" wide rims, but I'll be darned if I'll spend $2K on a new set of wider rims just to get that at this point. I am not a tame driver, no issues concerning wear and I prefer aggressive alignment specs too.

Now if your thinking about buying 7.5" wide rims, and 245's, well definately keep looking and get 8" wide rims instead.

"All that's necessary for the forces of evil to win in the world is for enough good men to do nothing.”
Edmund Burke

G35 6mt<P ID="edit"><FONT class="small"><EM>Edited by Gsedan35 on 06/17/04 01:46 PM.</EM></FONT></P>

 

It just depends on the tire. For instance Bridgestone and Michelin both list a 245/45 18" as good between 7.5 and 9, while Dunlop lists 8-9.5.

To be safe and to give yourself peace of mind particularly if you will be pushing the car hard at all, email the manufacturer and ask them what the implications are. Or, ask Buddy at Tires R Us if they will write down their guarantee for you that it is safe and the manufacturer will still warranty the product.

2004.5 Coupe/5AT/Ivory/Everything but front spoiler/Nismo CAI/Crawford V5