http://www.walmart.com/ip/Goodyear-Eagle-LS-Tire-P225-60R16-97S/2367646
Walmart has a great deal on P255/60R16 tires for Cyber week. Will these fit a 2000 Explorer? They are 60 instead of 70 for width, but other dimensions seem the same.
I don't think you quite understand tire sizing.
The WIDTH is the 255. It means the tread width is 255mm.
The second number (the 60 or 70) is the ASPECT RATIO. It is the "height" of the sidewall, and it determines the overall diameter, and rolling circumference of the tire. However, it is not a "direct" number. 60, or 70, or whatever, is not the measurement. It is a PERCENTAGE of the tread width (the 255, in this case).
So, a 255/60R16 has a tread width of 255mm, and a sidewall height of 153mm. A 255/70R16 has the same 255mm tread width, and a sidewall height of 178.5mm.
As you can see, a 255/60 is "shorter" then the 255/70 you need. Putting that 255/60 on will look funny, and more importantly, it will cause an error on your speedometer. Using a smaller tire then the ecm is calibrated for will result in the speedo reading faster then your actual speed. Further, it could cause problems with your ABS system, and even effect transmission shift points and engine parameters.
I can't imagine that the sale would only apply to one specific size of tire. Perhaps that was just a representative size in the ad? Either way, don't use the wrong size tire, just because its on sale; especially if you don't understand why its wrong, or what it could do.
http://www.tirerack.com/about/techcenter.jsp