The sad thing is that by trying to preserve the warranty (by not regearing) you'll be hurting your transmission. Pushing 33's instead of OEM sizes will be like having the truck on a mild incline all the time. That's added wear .. and you'll likely pay for it down the road ... after your warranty is gone, of course. The previous owner of my truck did the same thing and I've got a tranny rebuild in my near future as a result. 4.10's will be fine on the highway with 33's ... and will convey a slight bias for power. They'll take your truck from a dog to downright punchy off the line. They'll also provide enough of a power bias to allow you to move to 34's or 35's without regearing again ... something you couldn't do with 3.73's, as they're really only adequate for your 33's.