Black Soot / Poor MPG Issue

[Dog Licked Racing]

I just cleaned my 2004. 5 3500 DRW 4:10 rear truck and took it for a 1200 mile trip last weekend (this was total road miles 2200 to 3400). Almost all of this trip was Pen/Ohio turnpike at 60 to 70 MPH.



I am only getting about 12 1/4 MPG and thats both calculated and on the overhead/ The fender panel behind the rear tire blister above the tail pipe is black with soot all the way from the blister to the bumper and up just past the crease where the little running light is. I mean solid black on a white truck.



The soot and dropping milage (14. 5 now 12. 5) seems to be getting worse with each 500 miles driven.



Does this seem normal?

 

[Bill Stockard]

I have a 4. 10 ratio truck as you except mine is an '03 and a 4x2. Yes, the mileage was about the same on my truck when it had that low mileage on it. As your miles increase, and depending on your dirving habits, the miles per gallon will improve. I have over 12,000 miles on my '03 and it's up in the 17s and 18s. I keep an accurate record of all my fuel purchases on Microsoft Excel which averages the fuel mileage.



Also, I had to put a tailpipe extension to prevent the soot from accumulating on the rear quarter panel. In fact, I've owned 3 previous Cummins powered duallies and they all accumulated soot on the rear quarter panel with the standard tailpipe. If you'l look at my "Reader's Rigs", there is a photo of the tailpipe extension from Genos that I've used on my duallies to keep the soot off. It still accumulates somewhat on the rear quarter panel of the Lance slide-in camper that I haul.



Bill

 

[JCotte]

No. . It is not normal... Get it to the shop

 

[PHX ATC]

Not normal. Maybe a turbo/intercooler line loose. Too much fuel and not enough air. Air filter, maybe?



Check the obvious stuff and then take her in.

 

[RJBussey]

Dam mine leaves black soot also all over the rear. And I mean bad. In a 200 miles trip empty I have alot of black.

 

[RJBussey]

Well I just talked to my local dealers Service Department's Manager and he told me it is normal.

 

[swexlin]

You and I have the same truck, color, everything. Yes, I get a some soot stains back there, but never see any black smoke, etc. This is just normal buildup. Unless you are having performance issues, I think you're OK.



You mileage and mine are about the same. Remember, you're driving a truck that weighs almost 4 TONS, with an automatic, and 4:10 gears. If you go up and down hills, 4-way stops, and traffic lights like I do, plus "do or die" intersections without traffic lights, where you have to literally STOMP on it to merge into traffic without getting hit, then mileage REALLY takes a hit.

 

[BBailey]

My 04. 5 2500 QC with 3. 73's & auto is doing the same thing. My 2001 with NV4500 3. 54's & 305/70/16 tires didn't do it nearly as bad & I drove it a lot HARDER. I even keep Stanadyne Performance blend in it to try to boost the mileage that is so far SUCKING! That is supposed to reduce smoke too. Don't know what it would do without it. The dealer says there is nothing wrong with the mileage but trucks identical to mine are getting 3-4 MPG better.

 

[JCotte]

My 04. 5 does not soot up my truck and it defenitley will lay out some smoke when you jump into the throttle. I don't know why they told you it is normal RJ. Ask them if they can run an emissions test on it. after all, it has a cat on it and soot should not pass through it to that degree. They say build up, I assume you wash your truck often enough that it would not build up to that degree. Someone posted it is doing that in 200 miles, that is NOT normal. tell them to fix the truck. :-{}