Quick tire question...
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Quick tire question...
I currently have Goodyear Wrangler "275/65r20 tires on my truck and its time to get some new rubber, I am looking at the Nitto "Dura Grappler's" they offer two sizes for 20 " wheels they are LT275/65R20 which is the exact size of my goodyears i have now they also offer a LT305/55R20....my question is the second number after the backslash designates wheel width??? correct? Example "275/65R20" The 65 means 6.5"?????? Could someone clue me in, and what are my options could I run the "LT305/55R20" on my truck??? I know very little about tires so thanks for any help!
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From: Smithers, BC, Canada
the first number is the nominal tire width in milimeters, the second number is the ratio of sidewall to width.
275x0.65=178.75mm=7.04" side wall
so 7.04" x 2 + 20" = 34" diameter
275mm is approx 11" wide
the 305/55R20 are approx 33" tall and 12" wide
Hope this helps,
JE
275x0.65=178.75mm=7.04" side wall
so 7.04" x 2 + 20" = 34" diameter
275mm is approx 11" wide
the 305/55R20 are approx 33" tall and 12" wide
Hope this helps,
JE
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Well just read in my inside door jamb it says i have 20"x8.0" rims....on nitto's site it list the LT305/55R20 in a chart of tires and says its "approved rim" is (8.0(9.5)11.0)...so i am assuming that my 20"x8.0" rims will work with this tire...?
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From: Smithers, BC, Canada
It should, as long as your wheel width fits withen the range recomended my the tire manufacturer, otherwise the tire can wear unevenly and more quickly.
Keep in mind that you will be loosing roughling 1inch in tire hieght by going to the 305/55R20.
Keep in mind that you will be loosing roughling 1inch in tire hieght by going to the 305/55R20.
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Joined: Jan 2009
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From: Smithers, BC, Canada
When I look at nitto's site the chart says that the 305/55R20 tire is 33.1" overall outer diameter
am I looking at the right chart?
Nitto Tire - High Performance Tires for Car and Truck Enthusiasts
am I looking at the right chart?
Nitto Tire - High Performance Tires for Car and Truck Enthusiasts
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What determines the size of your tires is the 55 or 65 by the first number which is the width between the inner and outer sidewall. so the 305's will be wider and shorter than the 275's. 305/55=33's 275/65=34's
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Sorry guy's I was looking wrong yeah your right.....so what are my options i wanna go with a larger dia. tire but i guess the largest for my application from nitto is gonna be the LT275/65R20...correct...
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BF Goodrich sells the KM2's that come in a 325/60R20 which is equivalent to a 35 inch tire. They might be a little more expensive but they are good tires. here is a link to the tire BFGoodrich Tires | Mud-Terrain T/A® KM2 | Tire Overview this is what I have on my truck. You can check out other tires from BFG also. This is just the one i know for sure
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I think i may just go back with the goodyears that came on the truck...they have 56,400 miles on them and have wore really good they don't owe me a thing...what i am thinking of doing is gettin 3 new tires and taking my full size spare and using that as a fourth tire and putting one of the old tires up under as a spare...i know I am cheap, have any of you done this...i mean as long as im putting the same tires back on whats the big deal right???...I dont want that nice spare to dry rot under there this way i can put it to good use right...do you guy's see any problems with doing this???
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From: Smithers, BC, Canada
I know people that do this with their spears and have no problems. The stock continental TRs that came on my truck are such garbage that I refuse to use them, so using my spear in the rotation will never happen