JimB

I'm sure this has been covered many times but I did some searching and didn't come up with an answer. I have some 18 wheels that I need to find some winter tires for. Last winter I used the 255/55/18s that came with the wheels and it looked pretty silly. Has anyone tried 265/60 (30.5") or even 275/60 (31")? I'm not worried about the speedometer, etc. Just rubbing.

Thanks for your help.
Jim

Cole

I would imagine they will fit without issue.

My 285/35/22s on 10" wide wheels fit and clear at every angle. The only spot they even remotely come close is when fully turned and going up a curb. Which I would imagine with a narrower tire on a narrower rim would put the corner of the tire further from the inside of the fender in a turn.

I'm currently running 255s on 18s for the winter with a 25mm rear spacer. Fits fine. (looks MUCH better with the rear spacers then the super narrow stock look)

Cole

FWIW the Transsyberia rally car had 265/65R18s on it. My understanding is that the cars had to be mostly stock from a motor and suspension stand point. Even if they were not, it looks as if the fenders are left totally stock which is probably the important part for you.

Bob Rouleau

If you drive in real snow you want the narrow 18 inchers, think function before form.

Cole

brad@tirerack.com

What he said! Please call me, I'll set you up. Thanks.

pdxjim

Or, if you want to go the used route. $1200.00 FOB Portland. And, easy to clean.

https://rennlist.com/forums/for-sale...rims-tpms.html

Andy E.

Unless you go the route of the slimmer 65-series tires as used on the Transsyberia, the 55-series stock tires on your 18's yield a 255mm footprint as compared to the 275mm footprint on that of the factory optional 275/40R20's. That's roughly 3/4" more tread surface that's put to the ground. This can hardly be considered too wide.....

While researching this same subject for my own GTS some months back, I realized that our winters are too long to run those ugly 18" snow tires/rims. Aside from saving money between the price of 18" snow tires and 20" snow tires, there really isn't much to look forward to by going with a smaller size.

Do yourself a favor and get rid of those "girlie" rims and get yourslf some real winter rims. Just save the sensors and the center caps for the new rims.

lowside67

FYI, the larger the tread width and shorter the sidewall, the poorer the performance is in snow/ice. A larger, softer, more compliant sidewall is critical to maximizing low traction adhesion.

Your 20" setup will be dramatically less effective than an 18" setup.

Andy E.

I wholeheartedly agree with this statement provided that it applies to a substantial difference between the two tire sizes. If you look at the above chart, you'll see that the overall sidewall height between the 18" and 20" setups is only 1-1/4". On a 14" rim, this would be tremendous but typically negligible on a 20" rim.

Again, IF the OP was a serious off-roader and needed that extra 1-1/4" sidewall height and 3/4" footprint.....perhaps I'd agree with your statement but I would hardly call it dramatical.

Bob Rouleau

Andy, Michel Lauzon put 20 inchers on his Cayenne and broke two rims on our bombed out roads. Now he uses 18 inch wheels with 255's. Check with your dealer. You are too into looks I think

JimB

I spent my first 20 years on a farm in North Dakota, the last twenty in MN and the 10 in-between kicking around the mountains around Portland so I'm pretty well versed in snow tires. I get it that its all about clearance and pounds per sq inch which is why tall and skinny work best.

Having said that, I love the looks of my GTS in the summer and don't want it looking like a wimp car 6 months a year. For me a good compromise would be 265/60/18s. I just need to figure out if a 30.5 inch tire on stock 18 inch Cayenne wheels will work.
Jim

Cole

FWIW, I decided to run cheapy factory 18s for winter. I HATE the way these wheel look stock but am kinda digging them in satin black. (run 22" for summer).

Too many curbs hiding under deep snow to run a real big wheel. These can be curbed without fear.

I put a 30mm bolt on spacer on the rear to make the wheels look better.

Andy E.

LOL! Bob, I don't doubt that the extra 1-1/4" will be the decisive measurement in saving a rim on a given nasty pothole; especially on Montreal's streets.

I also agree with what you and lowside67 mention about how a tall & slimmer tire will yield much better results in deep snow than a short and wide tire.

PAG does recommend the use of a 275/40R20 winter tire in their winter tire selection chart. However, they do not recommend the use of a 295/35R21 winter tire, but that hasn't stopped many GTS owners from installing them. Judging from the amount of Pirelli Scorpion Ice & Snow tires that I've seen for sale in a 21" size, the reasons are quite obvious.

I'm simply pointing out that the 20's (spec'd in a 40-series tire) is not that much worse than the stock 18's when it comes to traction in snow. 3/4" more surface contact can not make that much of a difference on a truck with a curb weight of 6,800 lb.

Frank 993 C4S

+1 - the same rationale I used. I looked so hard at BoobyC's 21" wheels hard but decided against them for pure functionality.