What is the largest size A/T tire you can put on a 2004 18" stock Rim? No lift kit, etc.

 

Generally speaking, a 285 series or 33" tire will be fine w/o any lift and on stock wheels.

 

Thanks, I appreciate your help.

 

Yeah...I was just at the tire dealer this morning to have a rotate done and asked the very same question and got the very same answer. Nitzer is on the money.

I didn't ask this question though. If you change your tire size to 285 or 33's, does that effect your speedometer reading?

 

It will affect your speedo reading, but only slightly. In this case, my guess is that if your speedo said 60, actual speed would be more like 62/63. Speedo re-calibration is relatively easy and there are lots of threads on here that detail your options.

 

Cool.... ...Thanks

 

http://www.miata.net/garage/tirecalc.html

Put your stock and new tire specs in and it'll tell you the difference in the calibration of your speedometer.

For example, my stock Lariat is 265/60R18. My current tires are 285/60R18 Nitto Terra Grapplers.

""
Speedometer reading with non-stock tire is 3.1% too slow.
When your speedo reads 60mph, you are actually traveling 61.9mph.
""

 

My buddy has 35'" BFG mud terrains on his 04 Supercab FX4

 

Of course, you might be able to possibly fit 35" tires. But it comes down to personal preference on how crowded you really want your wheel wells to look. Personally, that's way too much tire for a stock-height truck.