Hey guys, I bought the truck used w/34000 miles on it about a year ago and I'm unsure of what my final drive ratio is. I found something about the standard ratio on all Silverado 1500's in 07 being 3.42:1, but I'm unsure if my truck was special ordered w/3.73's or not. Mileage and acceleration lead me to believe I got stuck w/the 3.42's...but is there any way to find specs on what my truck came with? Unfortunately I don't have the window sticker or anything. If not, do any of you know what RPM I would be running at a certain speed and gear w/either set of gears and factory 31" OD tires? It is an ECSB 4WD/AWD LTZ. It does not have the Z71 package, but I know from some testing last winter that I do have a locking rear diff on it. If I do end up having 3.42's is it worth it to change out to 3.73's? What type of mileage hit would I take? I pull a 6x12 v-nose enclosed and will soon be getting a toy hauler bumper pull camper. I have a car to make my daily work commute during non-winter months, so a slight loss in mileage won't hurt me too bad. Thanks for any help in advance.