MPG woes

[dave186]

The downpipe on my 95 was easy. used a porta power and the big indexable prybar i just bought was probably the perfect tool for the job. Took me longer to chop the old flat pipe out.

Where are the up pipes leaking? manifold end or turbo end? They are kind of a beeeeotch to get to unless you have the trans out. I just rebuilt my E4OD and found a couple bolts missing on my up pipe so I put in new donuts too.

Another thing you could do is mod the IDM. Not sure if it helps with mileage, but it cant hurt and will make your truck run better. I just did it on mine and was impressed with what a $0.14 resistor did.

 

[Cheapthrillb2]

Yeah, unfortantly I didn't have a portapower or anything similar, just a block of wood and a pry bar lol.

If I recall right its the pipe coming off the pass side manifold, not at the manifold but where that pipe connects to.

My trans isn't long for the world so I will most likely take care of it then. It has 230K, truck has been 100% OE for 230K and the trans has never been out and the truck has spent more time hauling trailers around then not hauling trailers.

 

[Cheapthrillb2]

Well I must say kinda disappointed, other then maybe a 50* difference overall in EGT's and a cool sound I have noticed no other difference with having the MBRP downpipe and 4" exhaust vs the stock down pipe and the muffler/cat removed with the stock exhaust still in place.

 

[Jeep1947]

As far as cps goes they either work or not. Get a black one from International if you can just keep it in the glove box. Just my .02

 

[Cheapthrillb2]

I already replaced that for ***** and giggles. Have one in the glove box as well.

 

[f250sd]

how do you manage to get more than 12 MPG out of a 7.3 diesel . i have a 02 c.c. 4x4, can't more than 12 out of it. Hypertech stage 3, dyno flow free flow muffler, oem pipes.still unable to see more mpg out of ,yet there are claims, these psd get arouns 17-18. please help

 

[rthomas]

Try the bb in the fuel pressure regulator, I've done this to two trucks both were already chipped and the difference was very noticable in the upper rpm range. the best that I do is 10-14 towing anything with some wind resistance makes it closer to 10, dd is 17-18

 

[f250sd]

please explain what is th bb in the fuel pressure regulator, . love the truck but i wish i could squeeze some little more MPG out of it when empty. I get around 10 avg. towing a 9k fifth wheel.

 

[rthomas]

Adding a bb to the fuel pressure regulator will increase the fuel supplied to the injectors by about 20 psi, how this gives more power I dont quite know but it works. To do this locate the brass plug on the drivers side front of the fuel filter housing it is a 19mm remove plug carefully, under this plug will be a spring, remove it using small needle nose be carefull not to crush it. behind the spring is a plunger that can be pulled out with a magnet, when you get the plunger out you will see where spring goes, this is where you put the bb (.177 is fine or 3/16 if you can find one) make sure the bb is seated all the way to the bottem of the plunger and reassemble. Its a 2 minute job if you take your time.

 

[f250sd]

Thanks for the info, I'll try that. Hopefully the MPG's go up. I hear a lot of what seems to be b.s that the cummins,duramax get around 25 mpg. have yet to see one that does.

 

[u2slow]

I've decided not to worry about the economy anymore...

I'm convinced the folks that get these great numbers most likely can't do math, or have the F250 2wd with 3.55 and only drive empty, highway, and with a tailwind.

Its still better fuel economy and power than a 351W or 460 on a 7000+ pound 4x4 truck

 

[ckelly94]

Most of the fuel mileage game is in the way you drive. I drive very gently and do the speed limit mostly out on county roads or highway with my 99 4x4 lariat PSD. Even in 10-20 degree weather, i'm still managing 15 MPG and that's letting it warm up for a few minutes every morning in the driveway. In the summer un-laden, the truck gets 18-19 MPG with only an aftermarket intake/filter, and full 4" exhaust from the turbo back. I can't wait to see the results when I install a "juice with attitude" controller early next year.

Many of the people who complain about fuel mileage are actully doing the math wrong forgetting to account for thier bigger circumference tires.

 

[u2slow]

Heh... and what size gallon are we using?

3.78L (US) or 4.55L (Imperial)

 

[rthomas]

Ive never heard someone swear to more than 21mpg out of a cummins or 22 from a d-max, my cummins buddy (96 w/4.10s) has never gotten over 17. I think most of the guys claiming over 20 are either stretching it or driving like old people f**k (45) on the freeway, I have another buddy who has a 97 psd w/3.55s and a 5spd and he drives like cold molasses, he claims 19-20. I wouldnt spend much on mileage only upgrades, it will get self defeating in a hurry- if you spend $200 to get 2mpg how many miles will it take to pay it off? Instead I would focus on maitenence issues and not speeding instead

 

[ckelly94]

I agree with rthomas that purchasing upgrades for mileage only have a point of deminishing returns when taking the initial purchase price into consideration. I bought my truck with the expensive stainless 4" exhaust, and only spent about $75 on the RIFRAF DIESEL big filter kit.

The controller is going to be about $550, but I do pull horse trailers and a 30" camper that should help me on HP and mileage.

One thing I do religeously is use DieselKleen in every tank to keep things clean and happy.