Truck Forums - MPG between Ford, Chevy, and Dodge

I'm looking for some MPG info for turbo diesel Ford, Chevy, and Dodge 3/4 ton trucks. Looking for info on years around 87 to 95. I ask because next year I'd like to get a truck around this years and the MPG is going to be the main selling point when I ready to buy. Auto and manual info would be great. Anyone know of a website or websites that would have MPG mileage for the diesels? I have found it for gas engines but not the diesels. Any info is great appreciated.