Maybe there's something wrong with the trailer

 

should of gotten the srt -10

 

Heres some food for thought. I know you were playing with the tow/haul and what not, but even at 70, you shouldnt have been running 5300 RPM's.

Your truck is designed to haul a (load) trailer @ 55 mph, with the tow/haul on. This is where your going to get your optimum performance at cruising speeds, and in acceleration.

I have found, with the 4.7 and 3.55's, my truck likes to tow a 5000 lb load @ about 60 with the tow/haul on.

Just a thought. Not saying anybody is wrong...

 

Always said if I was gonna pull like that,I would get a diesel.Check the the Hotshot boys out.But seriously do you have run 70?,the air resistance at that speed is killing you.There is nothing wrong with your truck-it will pull stumps!.May I suggest running on the US routes if possible-a lot less crowded and way more scenic.Another thing,you cant fool the laws of gravity,what seems level empty, may be a slight grade.

 

How much does the trailer weigh? Does it have brakes? Were the brakes sticking at all? How were the bearings? Your truck should pull no prob. Does your truck seem sluggish without the trailer? Try pulling another trailer

I pull my 19' enclosed trailer packed with ATV's and gear (5000+lbs) and it pulls no problem and I can get around 10mpg. you should fix either your truck or trailer!

 

It sounds like there is something wrong with your truck if you were turning 5300 rpms at 70.

 

Agreed with the various points above:
- 5,300 RPM is about your HP peak and above where I would be towing
- Towing an empty trailer, even if it's 2-3,00lbs should be barely noticable

I'd look at "what is wrong with your truck " or "what is wrong with the trailer".

I tow/towed a 6,000lb trailer plus ~750lbs payload with both an '07 1500 QC 4x4 Hemi and an '08 2500 QC 4x4 Hemi. On the flats I get 10-12Mpg. In the mountains it drops down to 8 or so. If I'm pulling a steep grade, I run in 2nd at about 4,400rpm and put a piece of black tape over the mileage display.

On the flats, with the trailer/payload describe above, I really don't notice the trailer is there other than the overhead display with mileage.

 

i pulled a double axle boat trailer with the boat.. porbably weighed about 4100lbs. and my truck pulls it with no problem at all with or without a tuner and runs at like 2300-2500 rpms and i have 3.92 gears

 

if you slow down your rpm will drop. maximum speed limit for a vehicle towing is 55. also u said ur rpm goes that high when u have your o/d off. so thats normal then, to have higher rpm since ur in a lower gear at higher speeds.

 

As mentioned above it sounds like maybe your trailer brakes are sticking or something.