Bought this from my Dad a year ago. Excellent maintenance record. Does not have big tires. Has smaller V8. The exhaust that sounds like a boat. Why is the mileage so terrible (10 city/ 13 hwy) and is there anything I can do to improve the lack of power. I can barely get to 60 by the top of the on-ramps
i had a 2000 with the 5.2 motor and it ran great about 18mpg on the highway. sounds like you have something going on with maybe emmisions or maybe plugs or cap and rotor. if you can have the computer tested to see if you have any codes that can help. how does it idol?
In the old days (70s)vehicles that sounded like “boat motors” ended up having flat camshafts,we called them “ground round” this happened mostly on V-8 Chevrolets. Not saying this is your concern but the “boat motor” description brought back memories.
It idols great, runs great. The mechanic I and my Dad have gone to says it’s in great shape and well taken care of. I’m gonna bring it in again soon for a check-up (and ask these questions), since I haven’t done this since it has been mine. They have just told me this since they knew I was buying it. My Dad says that the mileage has always been horrible. I didn’t ask him about the power since I don’t want him to be sorry that he sold it to me. The exhaust system is designed to make that sound (of a big motor). Maybe that is the cause of the problems (as I call them). It just doesn’t sound like it can breath when I give it the beans. I wanna thank you for the response since it is so hard to get some input from anyone. Maybe if I replaced the exhaust system with a normal (quiet) one it would make the difference. Let me know what you think if you have the time. Thank you again
Jason
if you have a catalitic convertor, possibly on the way out. measure the exhaust diamiter ie 2 in or 2.5 in. some use 3in on these trucks and that doesnt give enough back pressure. does it have mufflers? guys like to run open pipes on a gas motor. not good unless its a pro stock motor.
I hate to admit to how little I know about this stuff, but I do know that it came stock with this truck and nothing has been changed in the exhaust system at all. It (the mileage and power) just doesn’t make sense to me. It doesn’t sound like it’s a common thing with these trucks so, sh**, I’ll just have it looked at for this issue alone.
sorry buddy. i know its hard to deal with when your not that mechanicly inclined. the convertor shouldnt be bad on a 99 vehicle. go to auto zone or similar parts store and ask them to check your computor for codes. they do this for free. is the check engine light on? does it come on briefly when you start the truck. may have bad o2 sensor. let us know.
Cats provide more the enough back pressure. Open pipes w/cats don’t hurt anything.