This is probably going to be one of the stupidest questions you guys have encountered.

I am getting a 2003 G35 coupe, 18in rims tomorrow and it needs new tires, like really bad. Front are 3/32 and rear are 4/32. So it has 245/45 18's on the front and 265/45 18's on the back. I want something cheap, but that will be a decent tire (under $800 installed). So I was thinking of putting 235/50 18's all around but have no idea if it will work or not. I was looking this up and have read about VDC and ABS issues possibly, but it's not a guaranteed.

I was looking at Pirelli P-Zero Nero's which are about $754 installed at Discount Tire but wanted to make sure it was worth the purchase.

I tried to look this up before and couldn't find a real definitive answer so I apologize if I looked over it.

Thanks.

 

No that's not right, you're much better off with 245/45X18s on all four corners. I ran that size all around for over a year and worked great. The 50 series might throw your speedometer off causing issues you don't need/want.
Gary

 

the front are suppose to be 225 and 245 rear staggard.. i dont see how you can run 245 on all four corners gary C?

 

Its not that much of a difference, I ran 245's all around on OEM 19s for months without issues.

 

I'd go with either factory sizes or 245/45's all around - either will work fine. 235/50's will be 4x4 city.

If you don't necessarily need the stickiest performance tires available for frequent at-the-limit driving, then I'd suggest considering the Kumho LX Platinum tires. They ride quiet and smooth like butter, and their treadwear rating of 600 is the highest I've ever seen. I have them on my car in factory sizes all around, and I couldn't be happier with them. You should be able to get into a full set of them for $750-ish or less, mounted, balanced, out the door.

Also, to extend the front tire life, you should really get a set of better compression rod bushings. Energy Suspension is one option, and you can get them from me for a very good price. I have them on my car, and I got 45K out of my last set of front tires.

Welcome to the G35 owners' group!

 

The magic formula for our car's VDC to be happy is to keep the rolling diameters of your tires F/R within 3% of each other. Your car doesn't give a **** if you run 14" rims, 24" rims (but we do ), fat tires, skinny tires, etc. That's why you see people running staggered set ups that work, they carefully choose their tire sizes to not upset the apple cart.

What am I talking about you might ask? I use this site to help me determine what will work and what won't. http://www.miata.net/garage/tirecalc.html

So let's look at a stock setup for the coupe that had 19" rims staggered tires. Plugging in those tire sizes into the calculator you'll see the 225/40/19 Front tires in this set up have a rolling diameter of 26.1" and the 245/40s are 26.7". That's a difference of .6" or 2.25%. So no issues. So say you think your front tires have a little too much sidewall and you want to go down to a 225/35/19. Sounds like a simple decision, right? Well doing the math the 225/35 will have a diameter of 25.2" or 1.5" different than the rears for a difference of 5.6% and your car will hate you and throw VDC and Slip lights all day long and probably go into limp mode.

So theoretically OP could run his 235/50/18 all around with no issues but I think those tires would be too tall for me. I like Gary's idea of running 245/45s a lot better. Hope this helps, let me know if you have any other questions

 

Just because Nissan runs 225s from the factory doesn't mean there always right, look at all the $$ they can save by going a few sizes smaller in front. I ran 245s on all four corners for over a year without issues, it gives our coupes a more stable controlled ride!
Gary

 

I bought my car used with 245-45-18 all 4 corners. when driving in heavy rain the car would sort of float thru the turn with the back end sliding out. My heart was in my throat in many cases...I feel the VDC was not working properly...I changed the front two tires out with the Kumho Platinum 225-45-18... now the car behaves really well also with a very quiet plush ride.

 

I ran 245's at all 4 corners on mine and it did great. I just cant remember if they were 40's or 45's

 

Cant run the same size all around w/out having VDC issues.

Some threads on it,

https://g35driver.com/forums/wheels-...-question.html

http://www.myg37.com/forums/brakes-s...-now-this.html

http://my350z.com/forum/wheels-and-t...lip-light.html

I'd stick with the oem sizes as the oe wheels don't allow much in the way of plus zero sizing.

 

sorry to thread jack, but i was wondering if you guys knew if 235/40/18 in the front and 245/45/18 (stock size) in the rear works on the coupe and won't mess with the vdc/slip? thanks!

 

Neal I'm going to respectfully disagree with you here. First, the threads you posted don't address running the same size all around, they all talk about people changing tire sizes and that's what caused the issues. All our cars really care about is that the rolling diameters of the tires F/R is less than 3% different to be happy. This has been discussed and proven many times over on this forum. So by running the same sizes all around you are actually making the car very happy.

I ran 235/45/18's all around when I bought the car and then rolled on 245/40/19 all around when I was on coupe 19's and never had an issue. And remember,every 03-06 sedan produced came with same size tires all around on either 17" or 18" rims.



So taking into account what I just said above you need to figure out the difference in the diameters of your tires. This is a great site to help you with your calculations: http://www.miata.net/garage/tirecalc.html

The diameter of the 235/40 is 25.4" and the 245/45 is 26.7". That's a difference of 4.9% so your car will hate you and throw VDC, Slip, and possible ABS lights/codes and more than likely go into limp mode if you try to drive it that way. Your front tires would be 1.3" shorter than the rears and that won't work on the G. You'll have to change the sizes either front or rear to get w/in the 3% difference. Use the calculator I posted above to help you.

 

Well put.

 

Thanks man, it took me a while when I bought my G to figure this out.

 

got it! thanks alot !