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30 mpgs

2K views 17 replies 11 participants last post by  Bluedually4x4 
#1 · (Edited)
Hey Im trying to get way better fuel economy out of my truck. I had a plan to make a highER horsepower truck for drag racing, towing, and daily driving. But I recently got a job as an independant contractor for directv and have chaanged my mind. I will have satellites and other equipment. It will only be 3-400 pounds. Not much weight at all. With my job i drive somewhere around 150 miles a day. So now I want to make a daily driver truck for fuel economy.

I'm not looking for power at all but if it comes, thats cool too. I want to make somewhere around 25 - 30 mpgs. I remember reading an issue of DPM a year ago or so Jeff Garmon made that Dodge ram 1500 with 700HP and still made 55 mpg with a light foot. I think he was running 32* or 33* timing. Now I know I'm not going to be running something as extreme as that but I dont see 26* or 27* being a problem. What would I need to run somehwere around there? I'm thinking Ill need a thicker head gasket and some ARP head studs. What else can and should be done? I will only be using my truck for long drives, hardly any city driving, and barely any load. Thats why I figure it wont bother me too much if it idles funny. I have yet to install my 4k gov springs but will next sunday. Maybe a slightly bigger injector and and maybe an HX40? All I really know of that helps with fuel economy is the timing. Any input?
 
#3 ·
I'd like to do something similar with my truck. It's '96 2500 2WD auto that is never going to tow heavy loads. It has a topper on the back. My plan is to advance the timing a little bit (15.5-16 degrees) and add a FASS system. I'll probably either have the stock injectors re-worked or replace them altogether. I've been thinking about lowering the truck, as well. When it comes time for new tires, I'll get the tallest/narrowest ones available (some BF Goodrich T/A commercial tires). I've got a pair of electric fans that I'll throw in there, too. My goal is to get better fuel economy than my little Mazda pickup, so I'm shooting for 27mpg. I probably won't fold in my mirrors or put duct tape on the wheels, though (as they did in the article).
 
#7 ·
yea that was a cool article but i dont want to fold my mirrors or put duct tape on my truck. Where did you get your electric fans? Ford Taurus:hehe:jk, but seriously, i have only seen a handful of people who run electric fans and dont know if theyre worth it. I really need to see better mpgs from my truck with the ammount of miles i drive now. Im sure with timing and a few other things,I should be able to see 30 mpgs. My truck is only a single cab 2WD. Much lighter than the 4x4s and less wind drag too, my tranny is built. so i wont grenade it with timing. Ill check my tire pressure in the morning. I think i have them at 60 or 65.
 
#6 ·
There are a few other things one could do to maybe improve a bit on what diesel power magazine did.

1. Check rear brake adjustment on trucks with rear drums to ensure there's no brake drag at all with brakes not applied.

2. Check and adjust wheel bearings on the loose side of normal-not too loose, just a little looser than you might normally do.

3. Replace transfer case oil (if applicable) with synthetic oil. Do the same for front/rear axles. Use oil at the low end of the recommended viscosity choices.

4. Run thinnest allowable engine oil.

5. Advance timing.

6. Run front tires at 80 psi, not 70 like this article stated. My experience shows that the tires won't prematurely wear the centers at 80 psi because of the engine weight.
 
#8 ·
1. Im doing my rear brakes as soon as i have some time. my only day off is sunday.

2. what do you mean run the wheel bearings a little loose? are you saying to not completely pack it with wheel bearing grease? Im not to sure about that one.

3. My truck is only a 2WD but I did put a maghytec diff cover on it with synthetic oil.

4. You mean put 5w40 instead of 15w40?

5. I want to put my timing somewhere around 23 - 26 degrees but I dont know the downsides of doing this. I will rarely be doing any city driving so i think my engine would run fine. Any info on this would be awesome.

6. As I stated above, I will check my tire pressure tomorrow morning and get them to 80 or so. It makes sense what you said, so maybe ill try it out. i spent 1400 on my tires so it will suck if i start to see uneven tread patterns.
 
#9 ·
thats insane on my third gen i did the same test and on the lieometer i got it up to 34mpg going 50 mph was about 1200 rpm doing it at 60 sounds harder
 
#10 · (Edited)
I also remember some vortex inducers somewhere that break up the turbulence behind the cab and tailgate that seemed to help. There are some companies that make them I know....or at least they did a couple of years ago.

Here is a white paper that's also very informative: http://www.komfortkruisers.com/PDF Docs/Diesel MPG Secrets.pdf
 
#12 ·
For now, I'm just driving my truck to get a "baseline." I plan to add some aerodynamic modifications to it over time, the biggest of which being a "modified tonneau" cover. It will go from the top rear of the cab to the top rear of the bed.
 
#16 ·
well, maybe ill judt fire ring the head then, or o ring it. i know im not going to be stock but im not going to go crazy with this truck anymore. Ill probably make a set of compounds using the Hx35 and match some injectors with it. I built my tranny to hold around 600 hp. but ill never see those numbers. i cant put any bed covers on becasue i haul satellite equipment with me all the time. I want to get great mileage because I will be doing 130-150 miles a day. I still want to be able to take the truck out to the track, do dyno pulls, and have fun on the weekends, ya know?
 
#18 ·
Tires. All season highway tires.
 
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