Clock just flipped over 140k and for the last three 1,300 mile trips the beast got a solid 18.5 m.p.g. empty @ 70 m.p.h. - hand calced. Loaded mileage is hovering @ 11 m.p.g. same speed. Still experimenting with the 5.9L air filter so don't know if it's 1. The beast is finally broke in. 2. Finally got all the "winter" blend out or, 3. The 5.9L air filter.
He still throws alot of soot when I hammer him and the rear quarter panel blackens within a week. NO complaints about the soot, but any increase in fuel mileage sure helps out on the ol' bottom line.

 

140K on an `07.5 RAM

How many miles a week do you drive ?

 

How loaded are you? My 5.9 got 12-14 towing 10,000# 12' 6" FW at 65ish.

Last week I picked up a 13' 6" FW, 12,660# and got 9.7 mpg towing at 55mph on I80 from Ohio to NJ. I've been put off on the 6.7 based on lousy economy reports... but maybe I should look at them again... dunno

 

[QUOTE=davelinde;2148795]How loaded are you? My 5.9 got 12-14 towing 10,000# 12' 6" FW at 65ish.

Last week I picked up a 13' 6" FW, 12,660# and got 9.7 mpg towing at 55mph on I80 from Ohio to NJ. I've been put off on the 6.7 based on lousy economy reports... but maybe I should look at them again... dunno[/QUOTE

I average about 150k miles a year.

Tow different sized units each trip. The last three were all 5'vers over 30' with minimal wind.

Fuel mileage has been my biggest gripe with this truck. My 04.5, as in my sig., would easily get over 20 m.p.g. @ 75 m.p.h. empty and about 13 -15m.p.g. towing. By the time the 04.5 hit 200k miles it would get fantastic mileage pulling no matter what was behind it.

 

Well if it does take that long to get it broke in then maybe it also means that they go to 2,000,000 miles instead of just 1.M

 

My milage is around 15 empty and when pulling my toy hauler its about 9.5 to 10. My hauler is 38 ft long and weighs about 15500 loaded. I usally tow at 70 +

 

I believe there is a TSB for this complaint, I don't have the # at home maybe someone else does.

 

mechanically, you should make it to 2 hundred thousand... but i really doubt the electronics will.....

 

He still throws alot of soot when I hammer him and the rear quarter panel blackens within a week. NO complaints about the soot, but any increase in fuel mileage sure helps out on the ol' bottom line.[/QUOTE]

Mine also does this. No complaints. The increase in fuel mileage is definitely worth a dirty fender.

 

Well, if you're pushing a chunk of black smoke, that would be unburnt fuel and there is at least SOME reason for a drop in fuel mileage. Wouldn't a chip that advanced the timing in these engines be a solution to a lack of power and fuel mileage ?

 

Yes except advancing the timing will also clog the DPF up and make you go into regen more often, causing a decrease in fuel economy.

GMScott, it sounds like you have a cracked DPF. Or has yours "fallen off," apprarently all on it's own?

 

Nah, DPF is still on. Wish it would "fall" off. Mine is an early 07.5, actually the first 6.7L my dealer ever saw. Had alot of EGR problems after 30k miles. A couple cleanings, some flashes and a warning to quit using diesel fuel additives seemed to end the EGR problems. The techs at my dealer hadn't even taken any training on the 6.7L by the time I started having problems. I complained about the soot WAY back then but they didn't know what to do about it. Now they claim to have a TSB which includes them driving it for 45 minutes after some flash but I really don't want somebody with no financial responsibility to my truck out beatin' the crap out of it for 45 minutes on the highway. Especially now that it is off warranty. Already asked if I could go with them but was denied due to "insurance" reasons. It has smoked since it started having the EGR problems. No real performance issues except for the lousey fuel mileage. Now the fuel mileage seems to be getting better @ 140k on the clock.

 

You said the the EGR problems seemed to end after warning to quit using diesel fuel additives. They say the additives help to reduce sooting and increase cetane.....what could be wrong with that ???

 

Was told fuel additives cause more ash which is what the DPF collects and I personally saw the EGR valve all gummed up when they cleaned it twice. Stopped using additives and NO more problems. Got the "Perform Service" message on the overhead which indicates the EGR valve & cooler needed to be cleaned @ 70+k miles as per the manual. Now just got the message again @ 142k miles as per the manual said it should come.
I don't have all the answers, just have to go by personal experience. Only used fuel additives twice thru the winter because of the severe cold weather I was running thru. Don't know if was really necessary but it's hard changing my "old" ways.

 

Gosh -- Only 130K to go before I start getting better fuel mileage.....

I get 11.5 in town unloaded. 10.2 hi-way pulling 14,000#