I have a 2007 4.0 V6 with 77K & did 4 things that netted 30hp & up to 24mph on the highway worst city mileage 17mpg. K&N air filter, Pulstar Plugs - check these out at - http://www.pulstar.com/Main/PULSTAR-Home.asp?P=1
I have tried many products over the years but Duralube with the 0-15...