just wondering if any u guys had 31-10.50-15 on 15x8 rims. reason why b/c i have 15x10 rims and 31-12.50-15 but i was thinking of going to the narrower tire. to try and help on gas ( weight) and there is not a good selection of tires in the 31-12.50-15. i like the way the tires stick out from under the truck with the 15x10. thats why i wanted to see some pics of the 15x8 and 31's also dose anyone know what the ECT button is for on the auto trans

 

here you go. hope this helps

 

ECT- Electronically Controlled Transmission - gives you different shift points on your transmission. When its on, the shifts will be at higher RPM's.

 

ECT raises your shift points, so your trans shifts at higher RPM's.