i am going to start building my truck soon and want to find out what you guys think would be the best gearing for 35-37's on the trail as well and on the street because this will be a dd also 
bigorange- using the basic relationship...
4.10/28" = X/37" ....solving for the gear ratio "X"
X= 5.42 this means if you were to go from the factory 410 gears and 28" tires to 37" tires that you would need 542 gears to make the speedo read accurate again. Now, of course, the 37" tires are a bit heavier than 28" tires so standard procedure is to gear down just a little bit more to help turn those heavy meats...that means 571 gears, in this case. That's 5% lower than factory over-all gearing with tires taken into consideration. Just make sure the gears are pro installed and they will last just fine. ZUK
ps---the basic equation I used will work with 33 and 35" tires also.
I did the math for 33 and 35" tires below.....
35" tires = 5.12 gears
33" tires = 4.83 gears.
