Hello all,

I am have a set of 18's which I currently run 235/40/18 kuhmos (90% thread left) . Anyways, to make a long story short. 2 tires got a bubble on the sidewall, it sux since i still have PLENTY of THREAD LEFT. Anyways, the rims are still in very good shape and tires too. My tire guy said ONLY ONE RIM was outta round -slightly, but the GPS9700 Hunter machine fixed that. it was really minor. still runs smooth after the balancing.

I am planning to replace the tires to something better. Anyways, I wanted to move up one size to 245/40/18 toyos. read and heard good things about them plus the extra rubber is good. I was planning to plus the size to this. But is it possible to mount 245/40/18 safely on a 18x7.5 rim?
or am i stuck with 235/40/18 for my 18" x 7.5" width rims.

Thanks in advance. Any feedback would be cool.
-Anthony

 

245/40/18 will safely fit on 7.5" wide wheels. It's the narrowest wheel than can be uses. Only replace 2 tires, and put the 245's in the back.
This is a technique that TET uses sometimes to build their amazing track cars.

 

I went to Toyo's site and picked one high perf tire since we don't know which one he's using. A TS-1 245-40-18 ZR rated tire needs min of 8". 8.5" being ideal.
http://www.toyo.com/tires/tire_specsheet.cfm?id=2

Same with the Proxies all seasons.
http://www.toyo.com/tires/tire_specsheet.cfm?id=18

 

Yes. That is why they don't put them in the front.
If you have 2 245' laying around, and need to put 2 new tires on 2 7.5" wheels, it's fine.

 

Um the site does NOT specify if frt/rear is okay. It only says 8" rim is the min required width. Meaning, it's not safe to run a 245-40-18 Toyo tire on a 7.5" rim according to their site. Meaning regardless of which end you mount the tire, 7.5" is 1/2 an inch too narrow to safely run that size.

 

Dude, it's pointless to waste my time arguing with you all over the org. I speak from personal experience, and from seeing results.

 

I don't understand how anyone could recommend using a 245-40-18 Toyo tire on a 7.5" rim when the manufacturer clearly states 8" as the min width?

Not trying to argue. But it's pretty clear that at least Toyo doesn't recommend it. What's to argue?

 

OMFG. I don't recommend it, and i'm sure you've seen that i always tell people to use 8-8.5" with 245's.
It can be done though, and doesn't generally cause problems.

 

You don't??

Sure it can be done. You could probably stuff 265 width tire on a 7.5" rim.

 

Both of you guys have very good points. Thank you to both of you.

Now, considering that the tire mfr. states 8" width rims. my next question, which I hope is an easy one is...


How about 235/45/18? ... since 245/40/18 are not recommended. I know people on the org who run them, but like was said its not recommended.

Now, I have run 235/40/18 during the summer as your read b4. It was not too plesant (VERY FIRM), esp on those nasty bumps and potholes. Anyways, I was hopeing to get more meat on the rims hence the 245/40/18 thought but now see 235/45/18 as a hopeful possibility. - i know it crazy limited in tire and expensive. But I really love my rims. 7 spoke ace lolas (+40 offset) ---- look similiar to G35c rims --- i got plenty of compliments esp at dealer when i had car serviced.

Anyways, I appreciate everyone posting their knowledge, and being helpful to fellow orgers.

Anyways, Opinions on 235/45/18? much of a difference vs 235/40/18 .. more protection???

Happy Holidays,
Anthony

 

Well I would figure out what tire sizes come close to your required overall diameter. If you want a softer ride, you might have to increase the aspect ratio a bit. (ie.. like you are suggesting) You can find the recommended tire widths for Toyo tires on the links I provided. 245-45 tire will be 105.75mm tall. A 235-40 will be 94mm tall.

Also different tires of the same size are actually not all the same diameter. You might want to research the tallest 235-45 or some different types of tires. High perf tires ride the harshest. All seasons will ride softer etc...

 

http://www.miata.net/garage/tirecalc.html

 

Jeff: Those posts in here are Andy on my sn. I must've forgotten to log off at his house....

 

You can run 245s on a 7.5" wheel. I'm using 2k4 wheels w/ 245/40/18s. 2k4 Maximas come w/ 245s on 7.5" wheels.

 

Odd what is the stock tire brand/model? Toyo's site clearly says 8" is the min

 

2k4 wheels come w/ 245/45/18 Goodyear tires.

 

RS-A to be exact, rated for 7.5 to 9 inch wheels. http://www.goodyeartires.com/goodyea...8&sidewall=VSB

The 6th gens are having huge problems with these POS tires' sidewalls.

 

too soft or something?

 

Sidewall cuts out of the blue.

http://forums.maxima.org/showthread.php?t=360523

http://forums.maxima.org/showthread.php?t=362437

 

Maybe because they are mounted on rims that are too narrow.

 

Did you read the info in the link below??? Not according to GY.

http://www.goodyeartires.com/goodyea...8&sidewall=VSB

 

I did. Says 7.5" is okay. But the original poster is using Toyos which says 7.5" is not okay on their tires.

 

Jeff, that last post was directed to Mizeree X, not you.

 

Yeah I know. But I think he's point is despite Goodyear's site saying it's okay to run 245s on a 7.5" rim, maybe it's not that good of an idea in reality? Just a guess

 

I do believe that manufacturers build in way too much safety factors into their products thanks to ambulance chasers going after the all mighty dollar...

 

Well maybe not. Especially when you posted those sidewall problems. But why even do it? I would think it would make handling squirrely by doing that. The differences inbetween 225/235/245 is not that great. Certainly not great enough to take a chance, that's for sure.

 

You are right. Let me rephrase that. Manufacturers write in way too much safety factors into their products. Build them as cheap as possible and still make a good profit, then just tighten the usage specs and beef up the small print.

Case in point is the Falken warranty. I need to rotate these crappy 512s every 3K miles and NEVER use any tire dress up products on them...

 

I got 18×7.5 Rims currently on my 245/45/18 tire. I want an offset that will look the best with these on my car?? Any help

 

You just resurrected a 19 year old thread, it's best that you make a new one.

It sounds like you already have rims, so you can't change your offset now.