5 MPG to 20 MPG what will it take?

[SlideWRX]

get one of these until you fabricate that sleeping nook. the airdam I mean, not a new truck.


Enclose the bottom of the front end; most of the suspension is hanging out in the wind. preferably add a complete underbody that is smooth.

Even an NA diesel should get better than 5 mpg; fix that thing! The fuel system likely needs a *lot* of TLC to clean it up.

A turbo diesel is like a turbo gas engine; for a given *power* range, the turbocharged smaller engine is more economical for light duty use than the larger NA engine. If you already have the power you need, it really won't give you much fuel economy improvement to add a turbo. You would need to swap out the current engine for a smaller turbocharged one to see big gains from a turbocharged diesel.

How much fabrication are you willing to do to that cube?

Edit: Also, check your alignment. It probably isn't that good.

[Vwbeamer]

drove a truck almost exactly like this one for a Job I had in the early 90's and IIRC, it got 11-12 mpg.

Could be wrong, been a while.

First, as everyone has suggested, make sure it's in good working order.

second run a ad on Craigs list.

Third buy a Ford Transit.

JOKe.

Have you though t about lowering it?

I would try to get the truck lower. Also

[AeroModder]

Get a new engine. It'll be more bang for the buck than fixing that one with all the problems you listed.

[rmay635703]

Originally Posted by AeroModder

Get a new engine. It'll be more bang for the buck than fixing that one with all the problems you listed.

I tend to agree here, I'm all for fixing but a NA diesel with low compression is not the most enjoyable thing to diagnose or repair...

That said HOW much below the allowable spec is it? if its close and you can't afford to fix just add some sort of top tube to the diesel like MMO, 2cycle, Diesel Service or whatever. Your compression will improve a bit. I do know that the Ford NA 7.3 was very reliable for the most part but that was about its only redeeming feature (my father owned a casino bus craftmobile with one). It was not as fuel efficient as other diesel offerings but could run down the road with a cracked block and broken crank if you had to.

Next thing I would offer is if you want the vehicle to be more aero and you could tolerate a loss of area weld and cut the front of the box at an angle (not sure which would be most effective) to the cab, not sure how much it would help if at all. The other possibility would be to extend the rear a bit and add a slope at the proper angle to the rear doors if you could tolerate a lower door height.
Or just lower the hole roof down if you can tolerate less clearance that would do the most with the leave work.

Cheers
Ryan

[ShadeTreeMech]

Originally Posted by AeroModder

Get a new engine. It'll be more bang for the buck than fixing that one with all the problems you listed.

I agree 100%. You might even be able to find a powerstroke in a boneyard that might swap in really easy. And concerning the transmission, is the 3rd gear ratio 1:1 or overdrive? I suspect it is 1:1, meaning a transmission upgrade will be essential for getting decent mileage on the highway.

I must ask, what purpose will this vehicle serve? Unless you're prone to insane whims you must have bought it for a reason.

[rmay635703]

Originally Posted by ShadeTreeMech

I agree 100%. You might even be able to find a powerstroke in a boneyard that might swap in really easy.

I would tend to disagree on the powerstroke, you enter into another maze of model years, overpriced maintenance items and varying potential breakdowns depending on which year and type.

Another 7.3 NA (or even 6.9 if power doesn't matter), operating in proper form is probably bang for buck the best replacement value if you end up going that route.

Putting in a powerstroke you might as well put in a cummins or change the transmission to a MT. Sounds like too much investment for the amount of use the vehicle will likely receive.

My take
Ryan

[ShadeTreeMech]

The reason I mentioned the PS was due to the possibility of an easy fitment. Depending on his skill, I would say a 3.9L Cummins would do fine, and get better mileage, or even one of the Mercedes 5 cylinder diesels used in the Dodge Sprinter. The Mercedes is a true winner, with a higher red line and common rail injection.

In defense of the PS, I have a friend with a 96 F-250 with crew cab, 4wd, auto, and long bed, as well as a lead foot, and he gets from 19-20 mpg. So it can be a good engine, although I admit it being a bit overkill in the displacement area.

When I was on a diesel forum, it was common knowledge that adding a turbo generally improved economy by helping to reduce unburnt fuel. Assuming the fuel screw isn't adjusted from the NA setting, economy can only go up.

And again, the question is what purpose will the van serve? That will help with the question of how much to spend on a refitment of drivetrain components. If it sees little use, I'd say fix the engine.

[Angelus359]

Seriously, something is horrendusly wrong with your truck to get 5mpg...

My godfathers 10mpg escalade truck....

[ShadeTreeMech]

I wonder if people behind him can see anything with all the smoke.

I also wonder if he miscalculated the mileage.

[Ryland]

My friends full size school bus is getting better mileage, a semi with a full trailer should even get slightly better mileage!

Have you said what this vehicle is going to be used for?