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There have been many different people asking what will and won't fit, how big is this tire, etc.
Tire Stuff
This is how to read the sizes and calculate the size in inches.
The stock 18" size is 265-70-18.
The first number is the width of the tread.
The second number is width of the sidewall expressed as a percentage of the tread width.
The third number is the rim diameter.
Converting, 25mm = about 1".
Using this, the tread width is 265 / 25 = 10.6" wide.
The sidewalls are (265 x 0.7) / 25 = 7.4" tall
The overall diameter is 18" (Rim) + 14.8 (Two sidewalls) = 32.8"
The stock 17" size is 285-70-17
This becomes 285 / 25 = 11.4"
(285 x 0.7) / 25 = 8" sidewall
17" + 8" + 8" = 33" overall diameter.
Using this, here are some common replacements that people like.
Yokohama Geolander H/T-S GO51 in 275-65-18
275 / 25 = 11"
(275 x 0.65) / 25 = 7.15" Sidewall.
18" + 7.15 + 7.15 = 32.3" Smaller diameter than stock by 1/2".
BF Goodrich All Terrain T/A KO in 285-65-18
285 / 25 = 11.4"
(285 x 0.65) / 25 = 7.4"
18" + 7.4 + 7.4 = 32.8"
The largest ones you can fit without lifting are 305-55-20.
This works out to
305 / 25 = 12.2"
(305 x 0.55) / 25 = 6.7"
20" + 6.7 + 6.7 = 33.4"
Larger tires in width or height will start rubbing like crazy. These actually rubbed a little on mine and I needed to melt the tire wells with a heat gun to make them fit. See here about doing this. http://www.clubarmada.com/forums/showthread.php?t=1310
You can use this system to read any tire size and convert to see if they will fit. Smaller than 17" rims and you will have problems with the brake calipers fitting. Lower than 6" in sidewall and you will start having problems with off-road driving. Over 7" is preferred for off road. Under 5" and you will have problems on groomed dirt roads and potholes. You will also loose some ride quality and tow rating. Under 4" and you better start riding on freshly paved stretches.
The stock tires are All season Highway tires. All-season highway tires are good in most conditions but not optimal in snow or off road. The stock tires are poor examples of HWY A/S tires and really just stink in most conditions. Changing to a good quality tire will increase most tire properties. A/T tires increase poor weather traction and off road traction but add weight, may add noise, and may ride a little rougher than Highway tires. Makers can often design the tires to eliminate excess noise and rough ride.
Rim Stuff:
Larger rims give you better handling (To a point) and a firmer ride. They also allow for larger brakes. You give up progressively tow rating, mileage, acceleration, smoothness of ride or ride quality, rim strength, and gain weight and cost. Forged rims are more dense and less prone to cracking than cast. This allows for either stronger rims or more delicate rim designs while retaining strength. They weigh more per amount of material used as the metal is more dense. They are usually twice or more as expensive as cast rims.
Rim width is also critical. A rim that is too narrow will pucker the tire. This may lead to the tire breaking its bead and immediately deflating, causing a crash and destroying the tire, etc. A rim that is too wide will have the rim stick out as far as the tire sidewall. This makes rims prone to scraping curbs and breaking beads as well. Check with the maker to see what width tire you should get, usually 2"-4" or so wider than the rim width.
Rims come in painted, Aluminum, and Chrome finishes. Painted is the most resistent to weather, salt, etc. Aluminum is usually brushed or polished. These require a lot of maintainence to keep looking good. Expect to do a lot of polishing. Aluminum can often be clear coated to keep most of the shine of a polished rim but give them more resistence to salt, tarnishing, etc. If this is available, I"d go this route if you choose aluminum. Chrome is the least resistent to salt but very resistent to tarnishing. You will polish, but not as much as with aluminum. Keep a good coat of wax on them and clean the brake dust off weekly and you will be fine. For salt, wash and scrub them the day you get salt on them or they may start tarnishing and pitting.
Hope this helps.
Tire Stuff
This is how to read the sizes and calculate the size in inches.
The stock 18" size is 265-70-18.
The first number is the width of the tread.
The second number is width of the sidewall expressed as a percentage of the tread width.
The third number is the rim diameter.
Converting, 25mm = about 1".
Using this, the tread width is 265 / 25 = 10.6" wide.
The sidewalls are (265 x 0.7) / 25 = 7.4" tall
The overall diameter is 18" (Rim) + 14.8 (Two sidewalls) = 32.8"
The stock 17" size is 285-70-17
This becomes 285 / 25 = 11.4"
(285 x 0.7) / 25 = 8" sidewall
17" + 8" + 8" = 33" overall diameter.
Using this, here are some common replacements that people like.
Yokohama Geolander H/T-S GO51 in 275-65-18
275 / 25 = 11"
(275 x 0.65) / 25 = 7.15" Sidewall.
18" + 7.15 + 7.15 = 32.3" Smaller diameter than stock by 1/2".
BF Goodrich All Terrain T/A KO in 285-65-18
285 / 25 = 11.4"
(285 x 0.65) / 25 = 7.4"
18" + 7.4 + 7.4 = 32.8"
The largest ones you can fit without lifting are 305-55-20.
This works out to
305 / 25 = 12.2"
(305 x 0.55) / 25 = 6.7"
20" + 6.7 + 6.7 = 33.4"
Larger tires in width or height will start rubbing like crazy. These actually rubbed a little on mine and I needed to melt the tire wells with a heat gun to make them fit. See here about doing this. http://www.clubarmada.com/forums/showthread.php?t=1310
You can use this system to read any tire size and convert to see if they will fit. Smaller than 17" rims and you will have problems with the brake calipers fitting. Lower than 6" in sidewall and you will start having problems with off-road driving. Over 7" is preferred for off road. Under 5" and you will have problems on groomed dirt roads and potholes. You will also loose some ride quality and tow rating. Under 4" and you better start riding on freshly paved stretches.
The stock tires are All season Highway tires. All-season highway tires are good in most conditions but not optimal in snow or off road. The stock tires are poor examples of HWY A/S tires and really just stink in most conditions. Changing to a good quality tire will increase most tire properties. A/T tires increase poor weather traction and off road traction but add weight, may add noise, and may ride a little rougher than Highway tires. Makers can often design the tires to eliminate excess noise and rough ride.
Rim Stuff:
Larger rims give you better handling (To a point) and a firmer ride. They also allow for larger brakes. You give up progressively tow rating, mileage, acceleration, smoothness of ride or ride quality, rim strength, and gain weight and cost. Forged rims are more dense and less prone to cracking than cast. This allows for either stronger rims or more delicate rim designs while retaining strength. They weigh more per amount of material used as the metal is more dense. They are usually twice or more as expensive as cast rims.
Rim width is also critical. A rim that is too narrow will pucker the tire. This may lead to the tire breaking its bead and immediately deflating, causing a crash and destroying the tire, etc. A rim that is too wide will have the rim stick out as far as the tire sidewall. This makes rims prone to scraping curbs and breaking beads as well. Check with the maker to see what width tire you should get, usually 2"-4" or so wider than the rim width.
Rims come in painted, Aluminum, and Chrome finishes. Painted is the most resistent to weather, salt, etc. Aluminum is usually brushed or polished. These require a lot of maintainence to keep looking good. Expect to do a lot of polishing. Aluminum can often be clear coated to keep most of the shine of a polished rim but give them more resistence to salt, tarnishing, etc. If this is available, I"d go this route if you choose aluminum. Chrome is the least resistent to salt but very resistent to tarnishing. You will polish, but not as much as with aluminum. Keep a good coat of wax on them and clean the brake dust off weekly and you will be fine. For salt, wash and scrub them the day you get salt on them or they may start tarnishing and pitting.
Hope this helps.
