I want to trade my two rear 18x9.5 wheels for 17x8.5 wheels, and I need to buy new tires in the spring.

What size tires can I fit on an 8.5" rim safely? I know people throw 255s on an 8" rim all the time...would a 275/40R17 be safe on an 8.5" wheel? I'm trying to go with something a bit bigger than a 245/45R17. I figure I could probably get 265/40R17s but there aren't as many tire options for that size.

Looking at either Kumho Ecsta MXs, Falken Ziex's (though I don't care about all-season...I'm just looking for summer performance), Nitto 555RII's, or Fuzion ZRi's. Maybe the Supra 712s, but I really did not like those in the 245/50R16 that I had two summers ago.

 

Most manufacture websites will list what width rims they recommend for each size they sell.

 

245 45 17 or 275 40 17

 

Hmm all of the manufacturers sites that I've checked recommend a 9" or larger rim for 275/40R17 tires. 8.5" would be cutting it close.

Other option I may go with would be a 255/45R17. I know the 245/45R17 is what comes on these rims stock for a 25.66" tall tire, but I think I want a slightly taller tire to help with the gearing I want to go with.

Unless anyone thinks it'd be safe to go with 275/40R17s on a 8.5" rim even though the manufacturers recommend a 9" rim. I don't think it'd be terrible, but I guess I need to know if anyone has done it before.

 

I'm sure not everyone will agree but I consider the manufacture recommended widths to be just that, a recommendation. They need to have some sort of recommendation to protect themselves legally in case of failure. I'm not saying its a bad idea to follow the recommendations, I'm just saying they aren't the end all be all answers and thats that. You can run tires that are wider or more narrow that recommended and they can still fit, it just wont be a guarantee. And I mean a guarantee on fitment and performance. To be safe I think its a good idea to follow the recommendations, but you dont have to. I've run much narrower than recommended and I've read of people using much wider than recommended, both with good success. I personally think .5" off recommendations is no big deal but to each their own.

 

That's the way I was looking at it too. Thanks.

Aren't Nitto tires slightly narrower than most other brands as well?