I have a 97 3/** 454, 4L80, 4.10's. When towing in overdrive RPM is appx 2350 at 70mph, in drive I'm at 3000 rpm. I'm thinking about changing the ratio to 4.56's or 4.88's to raise rpm in OD or should I drop to 3.55's or 3.73's and just tow in drive. I pull appx 7500 lbs from Texas to as far as Utah and Colorado. Currently OD just seems to work the truck too hard and 3000 in drive seems a little hard on things. Seems that 2750 rpm at cruise would be more of a sweet spot. I'm open to suggestions. I have intake, exhaust, and a Westers tune.