spence08

I average right at 17 with about 90% city driving. I also have 35 inch mts. Surely something is not right. I could get that mileage or better flooring it everywhere I went. I hope you get it figured out. I would change the spark plugs if they have some miles on them. This may not help but for 30 bucks it would be worth it to me.

rohada

You'll probably have a difficult time digging out of that mileage hole with the above parameters. My lifetime with 15km on the clock is 20.7 mpg. 75% highway time and easy on the throttle, regardless of where it is driven. Specs for my truck are below.

BucketMan

These trucks are just straight up hit and miss mpg wise. It's the one thing mine does pretty well at, I have 3.73's and a far heavier configuration, plus a cap and do better in the city.

I'd try the plugs like someone else mentioned, especially now it's tuned. Order some 534's from rock auto, try 89 octane on a 87 tune and go from there.

56rat

I really appreciate all the replies. I will put back on my stock intake setup tonight and will put the AFR on ebay to hopefully recoup at least half of my money on it. I have messaged 5star tuning because their economy tune looks to be pretty good and I'd love to give it a try. Hopefully they will get back with me today. Also, My truck just crossed the 37,000 mile mark. I have no problem trying new plugs as well to see if that helps. That's why I am here, To get suggestions from fellow EB owners.

I realize since I drive a lot I should have purchased a car of some type but being here in Utah it's nice to have a truck for driving year around. Our winters here can get pretty nasty. I am learning as I go and as long as I can reach 16.5 mpg average i'll be happy. That's what I expected to see from day one. Thanks again, I really do appreciate it.

56rat

See, that's exactly what I expected before I purchased the truck! If I was seeing 17 average with 90%+ city driving I would be completely happy. I am seeing 14's while babying it. No hard up shifts or accelerating, etc. Even on my long road trip at 70mph I was only in the 15s. I don't think I've ever reached 16mpg yet.

After I go back to my stock intake what tune do you all recommend I run? ( until I can get a custom tune ) Should I go with the 87 or 91 tune? Which one do you think will give me the best mileage? I can't go 93 because I only have 91 here.

XFJunkie

Same here my best is 17 hwy 13-14 city

SkiSmuggs

I highly recommend 30-35K spark plug replacement intervals. My originals were dead at 40K with a lot of towing, but it ran badly for quite a while before I could barely tow a hill. Two had the centers gone and the others were gapped at .040. I will replace them again at 70K.

56rat

is it a fairly easy process? I haven't looked in there to see how difficult it'll be to get them out. Also, is it best to gap them at 28 or 30?

SkiSmuggs

Look for threads here and videos on You Tube. Some say it is one of the easiest spark plug changes they have done. Remember that 11 ft/lb of torque is barely snug. Too much and you crack the ceramic. Even dealers crack the plugs occasionally. .028 if tuned, .030 otherwise.

BucketMan

Its not too bad, prolly an hour total doing it the first. You'll need a 5/8" spark plug socket, some extensions, nothing too complicated.

Watch the YouTube video on how to undo the clips for the coil packs, they are a bit tricky, dont fret if you beak one, I did, all is well.

I wouldnt worry about an economy tune, from what I have read does not net a huge gain, if any and completely ruins the REAL aspect of this engine and thats the torque and get up and go, just turns the truck into a turd, not worth it.