My truck seems to be running great. It has about 230K miles on it. I'm not happy with the MPG. I made a run to Havasu about a week ago. She was on cruse control at 60 about 1700 RPM all the way. She was towing a small boat maybe 2000lbs with the trailer and 400lbs in the bed. She made about 14.7 mpg going and about 14.1 on the way home. Its about a 300 mile run. My question is what mods have you done that seem to help the mileage the most? I know some of you guys are doing a lot better.

 

Something is definitely wrong with yours. I usually net no less than 36.3368542lmnop MPG while pulling that kind of weight.

Not trying to be a jackass. Really.

Comparing one vehicle's fuel economy to others is not a subjective test as we all drive differently and every one of our vehicles is in a different state of tune and condition. Add in the variables called topography and prevailing winds and the mix gets even more inaccurate.

 

My truck (late '99 4WD crew cab, 8' bed) with AUTO averages 16 mpg on the freeway with no load other than my fat butt. If I tow a 10,000 # trailer it runs from 9-10 mpg. I do run a little lower tire pressure when unloaded (45 psi), then bump it up to 75-80 psi if towing. So my mileage is lower unloaded than those who run higher tire pressure. But I like the comfort that softer tires give me. Highway tires are harder than open tread tires like BF Goodrich AT's, so they get better MPG.

A manual transmission will produce about 2 mpg better mileage and sorer knees.

You can invest $30-40 in an infrared scanner at HDepot to scan your bearings, brakes, tires for excess heat when you stop for a break, which can indicate dragging, causing a loss in mpg.

Have you had a competent alignment shop check your front end for straightness? After I replaced the ball joints and front bearings, I had my truck aligned. He had to use an offset piece, I forget what it was called, to enable proper alignment. He said it likely was that way from the factory. He found no damage to the front end. He said that I might notice better steering and maybe some improvement in mpg, since the tires were scrubbing.

You can take a piece of chalk to a parking lot, draw a line across the tire treads, then drive about 200-300 feet in a straight line, no turning and look at the chalk marks. If uneven wear on the chalk, you have something to think about.
Larry

 

I get 14.1 to 14.5 in my local driving, I haven't made a highway trip yet so I can't help you there.

 

This answer... especially where he states he gets 36.3368542lmnop MPG.

See my signature for the MPG's I obtain driving my truck. Other than RiffRaff 4/4 wheel and rebuilt turbo I have everything sealed properly and all sensors are working as intended. Also, I have a ZF6 manual transmission.

 

Not if the clutch is built properly. I used to feel like I was pushing on a leg press when shifting gears, now it is very smooth and light since the SB clutch.

When buying these trucks we need to realize that great MPG is just not something we are going to get. That is OK because the guys/gals with the 2016-17 trucks don't get much better.

I wanted a ZF6 because I wanted the granny gear and positive control over what the transmission is doing. Putting a hurst style shift handle was just for the fun factor though.

 

LOL at cleatus. I'm with him though. I don't get much better than that empty - of course, I got a crew cab long bed 4x4, 6" lift, heavy ranch hand front and rear bumpers and 35" tires. And cruise control will kill mpg especially with uphill towing.

 

What is your tire size? Is it lifted? 4 wheel drive? crew cab? Topper? Lots of things to consider. In answer to your question about what you can do to help base economy, for me it was a new EBPV sensor and a streamlined topper. My highway mileage actually increases with the topper on vs off, it's got to be the wind that scoops into the bed. I also use a mix of Stanadyne Performance and Opti-Lube, but I can't really say if that helps mileage or not. Even if you are only towing a light boat I'll bet it scoops a lot of air. At 60 MPH unloaded on flat highway I can see pretty darn close to that 20 mark, hand calculated. Towing our light boat and loaded for camping it drops to about what you reported, although the road is not flat and level in Mexico and the stops are many.

 

4x4 Ex cab, auto std tires (60psig), there is a cab high shell on the back. 3.73 gears, hubs unlocked A/C on. No lift, 4" exhaust, Intake upgrade and no signs of leaks.
The CPS sensor has been recently replaced. The IPR has been serviced. The EBP tube was cleaned, but the sensor was not replaced, it looks OK at KOEO, (14.7).
It's also running Super Tunes safe tow tune.
I will get another bit of data over the holiday. I'm taking it camping w/o a boat this time. About 100 mile each way on the freeway. I have previously got as high as 15.5 MPG doing this route (Lake Skinner) with the boat and w/o camping gear at 60MPH on cruise. W/O a boat I will be running about 65 MPH

 

Have you checked your exhaust back pressure sensor or tube as of late? There is some thought that this sensor can/does have an effect on MPG's.

 

I cleaned the tube, and the sensor looks OK at KOEO 14.7 psig. I should have some data from the last run. what should the EBP look like?

 

My EBP is reading 13-14psi. I read it should be +/- 2 psi from your local barometric pressure, which mine is

 

Here's my mileage for almost the last ten years. Every single gallon of gas that I've bought is here.


The reddish brown line is the actual mileage per tank, the blue line is an average of the last four tanks. The 4-tank averages tends to even out my over-fills and under-fills. I live in Alaska, so it is easy to see that as the weather cools off and I am using 4 wheel drive more and doing warm ups, mileage drops. Prior to 2011, I lived in a town where my house was about 1 mile to where I worked, so the truck never really warmed up in the winter and so mileage was really bad. Now I am about 10 miles to where I work and the truck gets to warm up on my daily trips. Curiously, my best mileage occurred shortly after I got the truck before I upgraded the early 1999 air filter to the current AIS filter and housing. These best miles occurred in 2008 on long summer business trips in the interior of Alaska where I would drive from Glenallen to Anchorage on a single tank at 55mph to see what optimum highway mpg would be. I had four trips that year where I got between 20 and 23 mpg. In future years I was never able to consistently get better than 18mpg on identical trips.

 

 

9 - 16 mpg
4x4 auto