diggerdave38

Hi, I'm about to replace my original stock RDX tires, and I was wondering if anyone has tried to do a plus 0, and replace the OEM size 235/55/18's with 235/50/18's. I did some searching online and I haven't found an answer. Thanks!

MMike1981

if all ur doing is lowering the profile...no reason why u cant, tire is just more prone to sidewall issues

cwepruk

No issue with that other than your speedo will be 3% off. I'd look for a 245 tire if possible.

Carbon2008RDX

diggerdave38 – As cwepruk mentions, it’s best to go with a wider width if lowering the profile. This will keep the total tire diameter closer to stock and the speedo closer to accurate. Also, you’ll have a bigger “foot print” on the pavement hence better handling/traction. Below are some specs. I’d probably go for the 245/50/18 (Option 1). The 255 would be as close to stock diameter wise with only 14/100th of an inch difference but it might be an issue on the stock rim with the sidewall ballooning out too much.

235/50/18 27.25 you will lose almost an inch of ground clearance
235/55/18 28.18 STOCK RDX
245/50/18 27.65 Option 1 <--- Best Choice
255/50/18 28.04 Option 2

BigHatch

You'd only lose half the difference, just the half below the center of the wheel. Those numbers are overall diameter.

ccfoodog

Note - look at the specifications for the tire and it should tell you what rim width range that size will safely fit on.

-john

mav238

Obviously, you are looking for a "sportier" feel and look to your RDX with the lower profile tire option. In cases like this, unless you live in a dry state, no significant cold precipitation or ice, you are better off with the current stock set up and with good all seasons.
On the contrary, if you live in a place with little snow/ice occurrences, and want the sportiness, I still would suggest going with a Plus 1 option, 19" rim/tire, lower profile and summer tires on it, and keep your stock rims/tires for the occasional need for it in the Fall and winter.

If you want to rework the tires, you might as well do it right and save yourself any trouble down the road.

diggerdave38

Thank you all for your help. Now I need to decide if I want to change out the wheels or go with the tire recommendation.

BigHatch

go for the wheels!!!

Carbon2008RDX

Thanks BigHatch - You're right. I overlooked that. If diggerdave still wants to keep the stock rims then he should definitely go for the 245/50/18. The height difference would only be about 0.265 or basically a quarter of an inch loss in height.

diggerdave38

I wish I could have convinced myself to do the 19" rims with the tires, but I couldn't rationalize the price. I went with some 245/50R18 Yoko all seasons from Tire Rack. I also ordered a set of ceramic front pads to hopefully take care of some grinding.

Carbon2008RDX

What Yoko's did you choose exactly? What was your major deciding factor on them?

diggerdave38

I ordered the 245/50R-18 Yokohama ADVAN S.4's. I ordered them because they were rated relatively highly by Tire Rack customers. They have decent spec numbers as well. I didn't shop much outside of Tire Rack, and they don't really have many tires in this size to choose from. I needed a good all-season, and this model/make seemed to fit my needs.

I haven't thrown them on yet, but I'll update on their performance once I get them installed.

diggerdave38

The Yoko's are working out great. The handling is about the same as stock tires; maybe a little better in the turns. They're better in the snow than my old stocks even though they are a little wider. My speedo is registering speed over by 1mph if that (gauging it by comparing it to the speed on my Garmin and who knows how accurate those are). If anyone is considering going to a wider tire I'd recommend them.