Since their has been many posts regarding the 6.7, let me tell you about my tripto south Florida from Atlanta. I pull a 35 foot 5th wheel that weights about 12000 lbs. Now the truck pulls this weight without any problem.

Before the trip I had been hearing a loud tick from the engine when at idle. The only way I know how to decribe it, it sounds like a valve is out of adjustment. I called the dealer and was told to bring in in and they would take a look at it. They did and was told it was about to go into regen mode and would quiet down after this. They said to drive in at 65 cruise on and it would go into reg. I did this for 600 off and on miles. Nothing happened. Same thing returning. Nothing. Still ticking away.

Another problem I noticed, starting off I would get a shudder that you would feel until about 20 MPH and then would go away. BTW this was the first trip pulling the trailer. Truck now has 3000 miles.

Problem number 3 that nearly drove me bonkers. When I would start slowing down to stop, when the transmission would downshift from 4th to 3rd it was a very very hard shift. From 3rd to 2nd it was even worse. These down****s would shake the whole truck including the trailer. This took place in tow/haul mode and would not take place when I was not pulling the trailer.

Now the real subject most of you are looking for. What was my mileage? As most of you know there are no mountains between Atanta and South Florida. Going down my mileage was 10.3. It was 10.8 on the return. Not as windy. It would not be a pretty picture if I was driving in mountains. My speed was 65 with cruise control on most of the time. I did not like the the manuel shift of the tanny.

My wife and I both do not have high praises for our purchase of this Dodge truck. I did forget the old saying, do not buy a vehicle the first year of a major model change. I will take the truck to another dealer next week. I will post if this one is able to take care of my problem.

 

IIRC they have a TBS out on the shift problem while in T/H mode. Being you have a Mega cab they may or may not be able to fix the shudder problem as it has 2 drive lines and there are a lot of peopel who have this problema and they cant fix it 100%. As for mileage you only have 3K on it so I would think it may improve once its broke in and you get another 15,000 miles on it.

JMHO

 

My '06 has always had a little bit of a shudder when first getting started, even before the lift kit.

 

TSB 21-019-07

FLASH: 68RFE Transmission - Harsh Coastdown Shift And/Or Harsh 2-3 Upshift

 

These newer injectors seem to tick when they want to. I had all 6 replaced and a valve lash while in there and they still tick when they feel like it.

I would say pulling 12000 lbs at 65 mph and getting 10 mpg is about right. My truck will only get about 10 pulling a 9000 lb camper at 65. I just got my best ever towing mileage recently pulling my camper in the mountains to Gatlinburg TN from Greenville, SC. I got 13 for the trip, BUT the speed limit is 55 or under for most of the trip! BTW my truck now has 63000 miles on the clock so it's broken in as it's gonna get. I have a hard time believing people who claim 15 - 16 pulling campers, there is way too much wind resistance. Maybe with a different type of trailer that is not so high and broad in the front and doesn't end with a flat back but not a camper.

Go get the flash for the trans and see if that doesn't fix your shifting issues (I bet it will).

Let us know how it comes out. Good luck.

 

I read a post from a guy who had a one piece drive line made for his Megacab an so far no more shudder. He also posted that Dodge made one for the 2008 Mega cabs so those who have a major shudder should check it out. Oh he said the drive line cost was under $500.00

 

Just to throw in my .04 cents worth (inflation). My '99 powerstroke would shudder on takeoff when pulling my fifth (13-14,000lbs). It was the torque converter slipping. I fixed it with a Banks transcommand. I get an honest 11-12 mpg pulling this fifth on the flat land at 55-60 mph. Got a 6-spd. manual so no more trans worries.

 

Tom. . .what part of the Atl you on???

I'm on the south side in Fayetteville and commute to Atl every work day. Confederate Ave between Moreland and Boulevard near Grant park.

 

Hi Drew,

Sorry it took me so long to answer your question. I live in Peachtree City and retired. Sure would like to get together one day. I have read many of your posts.

Tom

 

sweeet. . .just around the corner. . .I live off HWY92 south just outside the city limit going twards griffin. the wife and I head over to the Kedron aquatics center from time to time to take the munchkin swimming. We cheat a little and sneak in since she teaches swimming and life guarding there.