I have a 98 GMC Suburban, 86,000 miles with what I suspect are OEM plug wires. I get 18 MPG at 55/65 mph on 200 mile trips; freeway and divided highway with a few stop and gos and very easy on the acceleration pedel. Same trip usually gets me 26 mpg on a 2001, V6 S10.
Bought the burban 2k miles ago and have flushed transmission and radiator and new plugs. I was expecting not more than 15 mpg but seeing 18 mpg is a bonus for this large vehicle.
Would new wires and new rotor do anything? Any other ideas on improving mpg short of driving 50 mph. Does premium deliver better MPG with this 350 engine?
hardworking