i have had a 94-94-96 97-98 and 2 2001,s. all 3.54 gears and manual trans..2003 and 2005 drw with 3.73 and 285-75-17 tires--6 speed, towed 45ft living quarters race trailer all summer..very good mileage up to 74 mph then it would drop about 3-5 mpg..pulled very good..cold air intake was a must..