285/40/17

[cjist1]

What would the tire diameter be on a 285/40/17 tire? Is it larger than the stock diameter....is it going to effect my speedo? I have 275/40/17's on my car now...but I need 2 new ones (yes the back ones) . I found some 285's for a good price and Im just wondering if I could get them without any problems.

 

[cjist1]

I think i may have answered my own question. according to tirerack.com the stock Diameter is 25.7" that is the same as 275/40/17. The 285's are 26.1". I dont think that .4" will make a significant difference....am I correct?

 

[dmsead]

I think i may have answered my own question. according to tirerack.com the stock Diameter is 25.7" that is the same as 275/40/17. The 285's are 26.1". I dont think that .4" will make a significant difference....am I correct?

As far as speedo error, it would only be about 1.4 percent, so that wouldn't be a problem. You might run into problems with rim width, though. the 285s are recommended for 9.5"-11" wheels.

 

[cjist1]

What type of problems will I have with having a 9" wide rim with 285's. I hope these tires work out OK. I should have done more research before I got them. The deal was really good though.

 

[StngStr]

Stock diameter is 25.68 and the 285 would be 25.98.

http://www.net-comber.com/tirecalc.html

 

[cjist1]

Stock diameter is 25.68 and the 285 would be 25.98.

http://www.net-comber.com/tirecalc.html

Well thats not too much different. I got my #'s from tirerack.com. Either way...there is not much difference in overall diameter. Now Im just worried that my wheel is too narrow. Its only 9" and It seems that the min. rim width is 9.5". I hope this doesnt matter too much.

 

[stangtrooper97]

I got my 285/40/17s on today. The speedo is pretty much as it was before. Not sure if I have any fender rubbing but it looks to be pretty much a straight swap.

 

[Slider]

I run 285/35's on a 18x9 wheel with out any problems. You will have no problems with a 285/40 on a 17x9 wheel.

 

[dmsead]

Well thats not too much different. I got my #'s from tirerack.com. Either way...there is not much difference in overall diameter. Now Im just worried that my wheel is too narrow. Its only 9" and It seems that the min. rim width is 9.5". I hope this doesnt matter too much.

I think it should probably be OK. It's only 10mm wider than what you had. I'm just glad that I'm not the guy that has to mount them. Fat-ass tire + stiff sidewall = PITA.

 

[bowens99GT]

Your good to go....285's will fit perfect. I got em on my 10.5 in bullitts.

 

[Slider]

I think it should probably be OK. It's only 10mm wider than what you had. I'm just glad that I'm not the guy that has to mount them. Fat-ass tire + stiff sidewall = PITA.

A 285/35R18 has a smaller and stiffer side wall then a 285/40R17. When I had my tires installed I asked the guys if they had any problems and the said it was easy. I asked because I had some 255/45R17 put on the stock rims a long time ago and the guys had to struggle a little to get them on. Just as a note I run 245/40R18's on 18x8's for the front, and the 285/35R18 on18x9's for the rear. The guy in this thread will have no problems with what he wants to do. Do not take what the tire manufactures as gossiple. They always seem to error on the larger side, but in real life you can also error on the smaller side with out any problems.