I had a couple of those Suburbans with 454 gas engines in the 90's. 3/4 ton chasis, 4WD, really good on the highway and turns, stiff suspension. No idea what my gas mileage was, so obviously it was not a concern. Just ordered a GMC 2500 HD 4WD with 6.6L gasoline. Dealer offered to 'let me off...