My mpg issue... Looking for input

[slcpunk74]

I just drove from slc Utah to Vegas and I am pretty unhappy with my mpg... On the way down I left at around 330am and just took my time and most the miles were done at around 73mph( speedo within 1mph) and I calculated around 15mpg on that tank but about 50 miles were done at 69mph and about 20 miles at 58mph with only about 10 miles around town and no hot ridding. All was done on the 100hp setting on my ts.

On the way back at 300 am I had a little side wind and went a little fast but no hot rodding and all was done around 76-77 mph, I checked that tank at around 13mpg with the ts chip on 75 or 50 I don't recall which.

I have a 4" lift and 33s but I'm going to drop it to 2.5" and go 35s which will lower my rpms a little and make for a little less wind but I don't know if it will make for better highway mpg. My tires were around 43psi and my speedo is almost dead on.I have mods that should put me in a better position in the mpg department but I'm thinking I need to do a fuel filter and maybe go with some php tunes.

Anybody have any other ideas I would really like to get better mpg for roadtrips.

[slcpunk74]

I know the lift can't be helping either and stock tire size is not really what I'm looking for FYI.

[Buffalo444]

the higher you get over 70, the lower your mpgs. just saying. theres a lot that goes into that but the speed limits arnt just for safety... most auto manufacturers design their vehicles to get the best mpg at average highway speeds.

[slcpunk74]

I understand that. This is nothing new that's why on the way down I went 73-74. I am wondering if a little taller and skinnier tire would take about the same effort to push but give me a little lower rpm and may e a bit better mpg or at least a couple mph higher and the same mpg.

[E'sStrokr01]

I've seen this many times about people getting 11-13 here, maybe 15 there......if they're lucky, so on.......and so on.

I'm waiting right now to finish the tank of fuel that I have so I can fill up again and get a good measurement to see exactly what I'm getting now that I have replaced both brake hoses on the front and one faulty caliper on the driver's side.

Not sure if there is a bulletin or whatever but I DO know that my brakes on the front were progressively getting worse and I didn't know they were even sticking until one day just recently I got a big odor of burning brake smell along with the front end starting to pull really bad to the left. Guy at the shop said he knew of many of our trucks that had front brake hose problems.

Now my truck runs great even in stock mode and I'm certain my fuel mileage has gotten back closer to where it should have been all along. It would be worth having your brakes checked even as much as you think they are probably ok. Just sayin.......

[Dietoremain]

i'd say its your lift and tires.. whats your bed/cab configuration too? my 7k truck gets 14/ maybe 20 highway on a long trip, depending. i cruise 65-72 usually.

[slcpunk74]

Xcab short bed. I would be stoked on 17-18 mpg cruising at 68-72

I am going down a couple inches and well see if that helps and I have a taller narrower tire I will try after that. I need tires that are narrower for the snow too... I spun out on the freeway a couple weeks ago on a small patch of slush.

[Jleof250]

My used to get 15 city 24 hwy when it was stock now 11 city 17 hwy on 6 1/2" procomp 35" tires.