Looking for the smallest diameter wheel I can run for a set of winter wheels without giving up load capacity. I have a '11 350 SRW with the 20" KR wheels from the factory and tow at max load. I want a set of dedicated winters, and would love to fit something like the Nokians on 18s (275/70/18), or smaller.

From my research, I haven't been able to figure out if a smaller wheel will clear my brakes.

Would love any input you all have.

 

Lower trim level's come with 17's so they would fit.

 

Brakes are the same on all 350s?

 

Yes............

 

My other concern is the load rating on the tires,

Current tires, Michelin LTX M/S2, LT275/65R20 3,750# max load. The 18" Nokians seem closest.

Winter tires,
Blizzak, LT265/70R17 is 3,195# max load
Michelin LTX Winter LT265/70R1 3,196# max load
Nokian Hakkapeliitta LT2 LT265/70R17, 3,200# max load

Firestone Winterforce LT275/70R18 3,640# max load
Nokian Hakkapeliitta LT2 LT275/70R18 3,640# max load

 

Thanks, I wasn't completely sure if Ford had an option for larger brakes.

 

If you are towing heavy on those tires, I would go with the higher weight ratings. Do those tires meet your towing needs? If not, maybe a snow rated all-terrain tire with a higher weight capacity.

 

They're all the same load range. Since these will be winter only, my thinking is that I want pure winter tires. I think the winner is the 18" Nokians here.

 

I wouldn't go smaller than 18" as then you start to lose speed rating too. or at least you have to be cognizant of it. One of the reasons the F450 with the 17" tires have a lower speed limiter set from the factory. Not like I expect you to be going over 80 mph towing - but I like to have more speed rating than I'll ever use. Kind of the same reason I got the F350 over the 150 or even a 250. I'll never be over loaded.

FWIW, I agree with the dedicated severe winter/snow tire philosophy.

 

I have to ask why do you want to go to the smallest wheels?
I can see going down to the 18's as you have more tire choices but the diameter of the tire should be kept the same.
(Fellow Porsche racer here ��)

 

These tires BFG KO2's are winter rated and have a higher load rating...

http://www.tirerack.com/tires/tires....lar=Crew%20Cab

 

3,640 is the same load rating that he listed for the Nokian's. I also like the idea of dedicated winter wheels/tires.

 

That's the same load rating. I'm picking up a set of 18" OEM wheels and have ordered at set of the Hakkapeliittas (which are regarded as the best snow tire available). We'll see how they wear, I do plan on towing the trailer a few times when I'm not in the mountains.

 

I tow at 55-65, I drive at 70

 

Smaller wheels have more tire sizes available, narrower tires handle better in the snow. Same reason I went with 18s on the Porsche