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Discussion Starter #1
So 235/50/18 are the 'stock size' for 18s but I was wondering how the 245/45/18 would compare. What are the pros to each size?
 

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245/50/18 = 9.64 wide
Rim Width Range is 7 - 8.5"
27.64 Diam
4.82 Sidewall
86.83 Circumference
725.5 Rev's per mile
60 MPH true

245/45/18 = 9.64 wide
Rim Width Range is 7.5 - 9 "
26.68 Diam
4.34 Sidewall
83.81 Circumference
779.6 Rev's permile
62.1 MPH
Speedometer 3.6% too fast
Diameter difference is 3.46%

HTH

Paul
 

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This has been recommended to me by several tire and mag guys that I have dealt with.

That possible typo confuses the hell out of me Paul!
 

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245/45's are alot cheaper cause it's a more "common" size than the 235/50's. I've been running 245/45's for about 4yrs now. Your speedo will read 2mph faster, but thats not a bad thing!
 

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Holy Crap !!!!!!!!

Don't know WTF happened there
let me try this one more time
Sorry

235/50/18
Width 9.25
Rim Width Range 6.5 - 8.5"
Overall Diameter 27.25 "
Sidewall Height 4.62 "
Radius 13.62 "
Circumference 85.60"
Revs Per Mile 763.3
60 MPH True

245/45/18
Width 9.64"
Rim Width Range 7.5 - 9"
Overall Diameter 26.68"
Sidewalll height 4.34"
Radius 13.34"
Circumference 83.81"
Rev Per Mile 779.6
Speed 61.2 MPH
Speedo Difference 2.135% too fast
Diameter Difference 2.1%

Looks like there are 14 or 15 more manufacturers/choices for the 45's as well.
 

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Damn, you guys are awesome. I bet they would be a bit cheaper.

I kind of like the look of the smaller wheel with my black rims, especially since I've lowered it.
 

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That is usually the case with low profile tires.
Higher the sidewall the better the ride, but you lose performance the taller you go.
 

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You can't really call a 245/45 a low pro tire when switching from 235/50. The ride quality doesn't suffer if you spend some decent money on tires. Now if you buy some $30 flea market tires then yes you could blame a shit ride on the 245/45 I guess.
 

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You can't really call a 245/45 a low pro tire when switching from 235/50. The ride quality doesn't suffer if you spend some decent money on tires. Now if you buy some $30 flea market tires then yes you could blame a shit ride on the 245/45 I guess.

I guess I made that comment "Sidewall height In General" not meaning to compare the two sizes that were mentioned here.
The 45 is "lower profile" than the 50 but only by 1/4 " +/-.
In this case you do lose approx a 1/4 inch of "cushion" going to the 45

I was meaning that a 60 or 65 series will ride nicer than a 45 or 50, and the 45 - 50's will be nicer than a 25 or 30 where the sidewall is getting down under 3 inches.
Might as well drive around on hollowed out hockey pucks.

Paul
 

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I posted about this very topic in the general post area, but didn't get any responses - still finding my way around the forum. Glad to see you guys having this discussion. I'm looking at the General G-Max AS-03 and the Cooper Zeon RS3-A tires in the 245/45/18 size. Judging by what I've read here, it sounds like there is no fitment issue and the size might ride just as well. I like the idea of a little more meat on the road. Have any of you guys heard anything about the tires above, or do you have any other suggestions? I put 25,000-30,000 miles a year on my car and I can't see spending the $1200-$1400 for the direct replacement Good Years. I need good tires that are going to be quiet, comfortable, and last 50,000+ miles. Also, have you seen any noticeable change in the gas mileage with the 45's? I would think with slightly less diameter, lighter weight, and slightly lower ride on the car, it might make a small improvement. I'd also like to upgrade the front shocks/struts to eliminate some of the roll in turns, but don't want to make the car too harsh - I know something about wanting cake and eating it too, right... Any suggestions there?
 

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Can I put a P245/55/R18 on my 2012 LTZ?
Ill advised to do so... Too tall aspect ratio so the speedo will be off big time. Do a 245/45-18 or stay with the 235/50-18. I'm not sure if the stock LTZ wheels can even do a 245/45 safely.
 
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