New owner.. any fuel economy tips, upgrades or parts?

[RysBlendOfChaos]

I have purchased a 77 m880, noticing the gas milage at around 10-12mpg. Just wondering if anyone has done anything to improve this keeping the 318 in it. A few things I have looked into which may or may not work are grooves in the head
- http://somender-singh.com/component/option,com_frontpage/Itemid,1/ - ignition systems such as msd or directhits.com which is supposed to boost the spark like crazy. Maybe a scam, but they have been given good reviews by legitamate sources. Im sure a good cam, intake/exhaust manifold, carb(500cfm?) would do something, im just not sure where the money would be best spent. I have also looked into propane conversions hearing mixed reviews. If I could learn from anyone elses experiences/mistakes that would be great!

 

[Elwenil]

MSD is a good upgrade and can improve fuel economy a little, but improves driveability a lot more. As far as any great improvement in economy, about the best thing you could do is swap to a manual transmission and swap in a normal part time front axle and NP205 part time transfer case. A gearing change may help, depending on the terrain where you live. Free flowing exhaust and the normal engine tune up mods can also help. Some Dodge truck owners have even had better MPG from one of the factory spreadbore 4 barrel carbs like the Carter Thermoquad or the Rochester Quadrajet found on 318s and 360s from the 70s to the late 80s. You just have to keep your foot out of it. Propane is cheaper but it uses quite a bit more propane to power the engine than it does gasoline so I'm unconvinced that is worthwhile modification.

 

[RysBlendOfChaos]

What are some of you other m880 guys running? Has anyone ever done a manual transmission swap with good results, and if so what tranny did you use?

 

[Elwenil]

The most common manual is the NP435 4 speed, which is what came in civilian trucks from the 70s to the mid 80s. You can also swap in a NV4500 5 speed which would gain you an overdrive gear which could help economy on longer trips.

 

[redbeard]

Hi. I just recently traded a 81 Ford class C RV for a 1977 m880. Runs ok,
body is beat but only a little rust. I'm not much into restoring but this
may turn out to be my first project. It's gonna be a work truck for me. I
live on 2 acres and no well. I haul water and just bought a 325 gal tank
that will fit in the bed. I may use italso for hunting, exploring, etc.
Just depends if the truck is truly as mechanically sound or not. I am a
terrible mechanic and need all the help I can get.
Now, is there a MilSpec repair manual of just use a Haynes/Clymer for the w200. I realize that the civilian manuals won't cover everything on the m880 ( suspension, etc.) I know this truck needs some rewiring. Light problems, fuse box looks sick, etc.

Any help appreciated.
Myles Lewis
Florissant, CO

 

[Bob H]

Mechanically the same as a civilian W200. suspension included.
There are TM's available on Ebay.
a handy reference is MVM back issue #79-MAY/JUN 2000: Dodge M880/M890 Trucks (11 pages) from http://www.swapmeetdave.com/MVBack.htm

Only $5 delivered and has awesome maintenence items in it., I have 3 copies, just incase!

 

[tractorfix]

I have found that a tonneua cover is usually worth 1-2MPG.

 

[redbeard]

thanks for the tips. guess the electrical issues are first, but that may wait tll spring. I'm way too old to work outside in snow.
Myles