Fuel economy report

[Rockwerx]

We did some more “testing” last weekend. Gross vehicle weight was just over 19,000lbs when we left. Our destination was 320 kms (200 miles) away. The first 200 kms we travelled at 118 kph. The last 120 kms we had to drive slower and slower (around 80 kph) due to the nature of the terrain and the last 50 kms we were on mountain logging roads doing less than 40 kph.

I started the truck to charge up the batteries a three times during the weekend and let it idle for 25 minutes each time. I was surprised to see the overhead display reading better and better fuel economy. Started at 9.1 mpg and peaked at 15.9 mpg US after the second time 20 minutes into the high idle. Obviously the computer programming is not advanced enough to know that you get ZERO mpg when the truck is idling and parked. It was only compensating from going from a high load factor to a low load factor. I topped up the truck from the aux tank and put in 110 liters. Actual fuel economy was only 7.24 mpg US. Not sure why it was so bad for this trip.

I drove slower on the way home. Set the cruise at 110 kph after we got back to the highway. It seemed to do better on fuel. I will post my results when I top it up later.

My truck will blow some black smoke now and I am wondering if I might have to clean the O2 sensors more often. Anyone have any thoughts on this?

__________________
2008 Ram 3500 Laramie Quad Cab 4x4 LB DRW 6.7 CTD 6Auto 3.73 LSD
EJA, EPP, MES, KAF, ABD, FHO, AFT, HIE, EBO, RWX
Parts keep falling off my truck...The latest in Blacktec technology added

[mileshuff]

Should not blow any smoke. Probably a cracked DPF.

__________________
2007.5 Big Horn 6.7L Ram QC 4X4 Auto A.R.E Tonneau

[floridagc]

Mileage seems bad, my 4500 after two weeks and 2800 miles, with 85/35 on the highway street, loaded at 13,600 with the truck and box and two trips each 100 miles with a enclosed trailer @31 feet long\, was reading 20.5 on the overhead, hand calculated was 19.1, the speed was between 60-67 mph on the highway.

flgc

__________________
2008 2500 Sport 4x4
2008 4500 Utility Box
2008 5500 utility box

[slagburn]

I'm pretty sure I read somewhere that Rockwerx has a DPF delete - haven't heard anything about having to clean the 02s because of the smoke, aside from what the dealer does for the P2000 codes.

__________________
07.5, 6.7, Auto, QC, 4x4, Lots of gauges - ISSPRO (Pyro, Boost, Trans Temp) PriCol Optix (Fuel Pressure Lift/Rail) AutoMeter (Oil Pressure) - Dynatrac Free-Spin Hub Conversion Kit - RETRAX bed cover - homebrew shaved bluetec badge - plugged up EGR - Baldwin BF1212 water separator and CAT 1R0750 fuel filter - MSD Dashhawk - Baldwin B164 Bypass Filter

[Rockwerx]

Originally Posted by slagburn

I'm pretty sure I read somewhere that Rockwerx has a DPF delete - haven't heard anything about having to clean the 02s because of the smoke, aside from what the dealer does for the P2000 codes.

Yes...a few things have fallen off my new truck that are supposed to improve the fuel economy. The mods were helping to improve the fuel economy till this last trip. If you get on the throttle hard it will smoke...especially if I use the higher power settings on the programmers. The inside of the tail pipe is black so I am thinking that the sensors are carboned up and giving the ecm a false reading. How does the O2 sensor opperate? Does heat (or in my case less heat) affect the way it opperates?

__________________
2008 Ram 3500 Laramie Quad Cab 4x4 LB DRW 6.7 CTD 6Auto 3.73 LSD
EJA, EPP, MES, KAF, ABD, FHO, AFT, HIE, EBO, RWX
Parts keep falling off my truck...The latest in Blacktec technology added

[Compcowboy]

I am not sure but mine also is blowing more smoke now then before. Dunno if its O2 related or not. I am interested in seeing more opinions or if it changes if you clean them.

__________________
??? Hp ???? Tq - 2007 6.7 TWIN TURBO 2500 Bighorn 4x4 6-spd Manual, Airdog 150, ARP Head Studs, Bullydog PMT, TS MP-8, Airbags with Dual Control Air Comp., H&S Delete & Downpipe, What EGR?, Valair Dual Disk, Amsoil Bmk-11 Bypass, 295/70/R17 Toyos on Walker Evans Wheels,6" Aussies & Hushpower Muffler & DiProcol Gauges & 120HP nozzles (on the way) Thanks to Wally At FTEDiesel!!!!!

[MuscleHead]

Originally Posted by Compcowboy

I am not sure but mine also is blowing more smoke now then before. Dunno if its O2 related or not. I am interested in seeing more opinions or if it changes if you clean them.

If your mpgs start going down i would try and clean them, this might have to be something done at regular intervals like fluid changes.

__________________
07 2500 TRX4 Offroad, 6.7L Cummins, 5" Pro-Comp Lift, 37" Toyo M/Ts, 18x10 Mickey Thompson Wheels,4:10 gearing,Amp Research Electric Steps,MIA Intake Baffle,Husky Liners front and rear,Bully Dog PMT ,H&S 5" Dpf Delete,K2 EGR Delete

[River-Runner]

Originally Posted by floridagc

Mileage seems bad, my 4500 after two weeks and 2800 miles, with 85/35 on the highway street, loaded at 13,600 with the truck and box and two trips each 100 miles with a enclosed trailer @31 feet long\, was reading 20.5 on the overhead, hand calculated was 19.1, the speed was between 60-67 mph on the highway.

flgc

Wow! You better thank your lucky stars.... That is about 6 mpg better than anyone else I have seen on here with that load. I can get 19.1 with my 2008 3/4 ton 4x4 auto at 55 mph EMPTY driving like GrandMa.

Does the 4500 have a different emissions set up or a different set of programming? WoW, 19.1 is great.

__________________
2008 White Laramie 4 x 4 2500 Megacab Auto

[CFNibertCC]

EB will cost you 1-2 mpg's if used all the time.

__________________
07 3500 C&C 6.7Aisin,4X4, omaha 10'fb, RC boxes, airbaffle? DPF? EGR & Cooler? bells? whistles?
01 2500 CTD 4X4 4" TBE 96 3.4L V8Taurus SHO

[LittleOleHotShotter]

I usually avg 8-9 mpg with 4 vehicles. Total Gross weight usuallly around 32k. Would get better if i didnt have a vehicles a$$ end up in the air acting like a wal above my cab. My dpf fell off at 35k miles and tip was spotless. EGR fell of at 62k miles. Got 87k miles now. Never blew smoke out that i could see even with a full load at take off with dpf. Once deleted i started puffing at WOT and take off. Once EGR fell off, i have seen almost no smoke. I can get over 20mpg empty at hwy speeds. Cant wait to see what the superchips flashpaq will do to my truck. If i get a nice increase, i might try the mp8 with it as a stack. I really wanna see 11 mpg with my truck with current trailers. Guess i need a low profile trailer or a 5.9 to due that.

__________________
6.7/6auto, afe, insight, 2 micron oil/fuel filters, riderites, 91 gallon aux, mag-hytec, amsoils - 115,000 miles & getting worked hard now - check out my truck pics
http://www.myspace.com/coopertransport

[MuscleHead]

Originally Posted by CFNibertCC

EB will cost you 1-2 mpg's if used all the time.

I cant tell a diffrence in mileage with or without.

__________________
07 2500 TRX4 Offroad, 6.7L Cummins, 5" Pro-Comp Lift, 37" Toyo M/Ts, 18x10 Mickey Thompson Wheels,4:10 gearing,Amp Research Electric Steps,MIA Intake Baffle,Husky Liners front and rear,Bully Dog PMT ,H&S 5" Dpf Delete,K2 EGR Delete

[floridagc]

My EB is always on, and the DF system is a little different than my 2008 sport 4x4, The 5500 is also close on mileage, bought them at the same time from NC, I think a lot maybe has to do with this state being so flat.
But the 4x4 in November was close to that on a 4000 mile hunting trip....

flgc

__________________
2008 2500 Sport 4x4
2008 4500 Utility Box
2008 5500 utility box