Hey guys,

Need some help with tire sizing and then tire selection. Take it easy on me as I don't know *%&^$# about tires.

Question number one: what is the difference b/w 31x10.5R15 and the P225/75R15. I know the former is considered the option tire but that is about the extent of my knowledge. I'm currently on some Dunlop 31x10.5R15

Question number two: when buying a new set of tires, should I buy a set of four or should I also buy a fifth for the spare? Can I just keep one of the old Dunlops as the spare if the new tires I purchase are also 31x10.5R15? I understand that this may largely be an opinion.

Question number three: tires. Looking at a couple of tires.
Toyo Open Country M410
Toyo Open Country A/T
Bridgestone Dueler A/T (D693)
Dunlop Radial Rover RV
Dunlop Radial Rover RVXT

Obviusly any other suggestions are welcome. I could really use your help guys. Thanks in advance.

Edit: not so quick this evening. I should mention my setup. 1992 4WD 2-door SR5 V6, no lift.

Lange

 

I have heard great things about the Toyo Open Country A/Ts ... those would get my vote, a far far better tire than the dunlops.

If your spare is the same size as the tires you're running, you'll be fine for the distance it'll have to last you before you get the blown tire replaced ... the trouble starts when you run big tires and a smaller spare ...

 

225/75r15 is smaller than a 31, a 265/75r15 is closest to a 31x10.50, my Tacoma came stock with 265's and i put them up next to a 31 and the 265 is just a little narrower, but height is darn close, and you can use the existing spare if its close to the size of the tire you're putting on the truck

 

also don't forget that ever make/brand tire may be a bit bigger or smaller than another brand in the same size. just keep that in mind ...

for example:
i looked at some MTRs in a 275/70/17 ... and that particular tire had an outer diameter of 32.4" ...
at the time, i was also looking at a Parnelli Jones Dirt Grip in a 265/70/17, and THAT tire had an outer diameter of 32.6" ... !!

so, it always depends on the specific tire.

 

the dueler or the toyos are good.. i personally dont really liek the dunlops

a 225/75/15 ends up being like a 28" tall tire......

 

Found a cool tire size conversion tool. Thanks for you help so far. The height difference is significant. 28.29" for the 225, as you suggested jimabena. Does the additional width of the tire (8.86" vs 10.5") make a big difference in terms of its ability to cut through snow? How does the additional height affect mileage? I'm pretty sure the 225 would look much too small, correct?

 

http://pw1.netcom.com/~sgalaba/tiresize.htm

Conversion program

 

the 225 would look pretty small, just like a 195/75/14 on the 4x2s.....

wider would help in snow especially for floatation, the only problem it might give you is ice, but ice is a pain on any tires.... none get traction basically.....

 

I always thought narrower tires were better for snow?

 

well its a mixed jury on that.. the same aplies to mud... you must look at what kind you are dealing with, do you plan to cut through the snow to find solid ground? are you moving so you will have momentum, are you stopped and trying to regain movment, do you have the power to spin the tires and clean the tread voids/lugs out? wider tires better in snow is subjective... i say wider is better as it provides better floatation

 

I've got Firestone Destinations:

http://www.tirerack.com/tires/tires....omCompare1=yes

I love em, they aren't loud, they ride great, they're self cleaning, and they kick @$$ out on the trails.

I've got a buddy with a Rubicon with Goodyear Wrangler MT/R's. He says he loves them, but they are a little pricy:

http://www.tirerack.com/tires/tires....omCompare1=yes