Should I be disappointed?

[dpatt67]

I made a run to upper Indiana to pick up a new travel trailer in my 13 2500. Unloaded going up I was impressed with the mileage as it was in the 20-22 range averaging between 70-80 mph. Coming back with the TT, mileage went to 7-9. This was with a TT that was around 8000 pounds and the average speed was between 65-72 mph. Also, the truck seemed to struggle with the weight a bit and kicked down a lot. Im not a troll, and I absolutely love the truck. It just seemed that my unmodified 05 handled that much weight better and didn't kick down hardly at all with the same kind of weight. The trucks were very comparable other than the figures(610 torque 3:73 gears 4 speed auto vs. 800 torque 3:42 gears 6 speed auto). Was I expecting too much?

 

[MelvinPierce]

Well, you went to 3. 42 from 3. 73's, and I believe the 6th gear is a higher overdrive than you have in your 05. So, it will shift out of 6th more. Try just holding it in 5th, which is probably about the same as you had before.

 

[TFucili]

I made a run to upper Indiana to pick up a new travel trailer in my 13 2500. Unloaded going up I was impressed with the mileage as it was in the 20-22 range averaging between 70-80 mph. Coming back with the TT, mileage went to 7-9. This was with a TT that was around 8000 pounds and the average speed was between 65-72 mph. Also, the truck seemed to struggle with the weight a bit and kicked down a lot. Im not a troll, and I absolutely love the truck. It just seemed that my unmodified 05 handled that much weight better and didn't kick down hardly at all with the same kind of weight. The trucks were very comparable other than the figures(610 torque 3:73 gears 4 speed auto vs. 800 torque 3:42 gears 6 speed auto). Was I expecting too much?

Frankly, I'd find that towing mileage a bit disappointing. How many miles on your '13? My '05 never got the kind of MPG that many others swore they got, and I drive pretty conservatively, unlike my younger, hammer-down days, but it did make two noticeable jumps in MPG as the engine broke in. The first at about 10K miles, and the second at about 30K miles. Maybe she just needs to loosen up a bit?

 

[dpatt67]

Yeah, it was at around 1500 miles on it when I hooked up the trailer. It has crossed my mind about the tightness of the drivetrain, I had just never seen single digits before this trip! My 05 even with another 5000 pounds on and behind it, the worst I got was 10, so it was kind of a shock, especially considering the new ones' excellent empty mileage. I'd noticed several others remarks about theirs getting much better mileage towing than what I have seen so far, so I suppose I just need to give mine time to really break in.

 

[Gonzo 1066]

My Dually 13 has mainly towed my horse trailer, combined weight is near 26,000# in 5,000 miles of towing in the mountains of the West all of my tanks have been over 10 with a high between Boise Idaho and Salt Lake City at 13. 5 hand checked. The front of my trailer has a taper and is not tall, I know that frontal area has a huge impact on MPG.

 

[JHumphries]

Was this trip over a couple of hours? If so, a steady tail-wind could have been helping you get up there, and then fighting you back down...

 

[NickSullivan]

^^^^That is exactly what I had in mind. I have the same thing happen just about every time I drive through the Gorge between Oregon and Washington. Big difference in MPG

 

[Gonzo 1066]

Was this trip over a couple of hours? If so, a steady tail-wind could have been helping you get up there, and then fighting you back down...

This was a nearly calm day. I do take into account those vairables in my travels.

 

[Powder Extreme]

Welcome to the joy of 3. 42 gears, it will shift a lot when towing. The mileage will get better after things loosen up some. Towing is actually one of the best ways to help break it in faster.

 

[Bug Out]

dpatt67, my 05 dually 6 speed with 4:10s bone stock would pull my current trailer at 8-9 MPG, no smog, cat fell off etc. . My 2013 gives me 8-9. 5 MPG at 24. 5 GCVW. I figure if the motor was not burdened with all the smog crap, and larger then the 5. 9, getting the same MPG, she's not doing bad. Gotta figure its a bigger engine with lots more smog crap to fight thru and still doing ok.

I found my truck hardly ever downshifted when i left it in 5th@ 65 MPH, but using 6th, would down shift on slight grades.

Just curious . Are you getting the RPM flare between up shifts from 4th to 5th to 6th gear? RPMs go up 2-400 rpm between gears? A noticeable RPM jump?

 

[sag2]

I took a brand new 13 to pick up a new travel trailer. 18. 3 mpg going down at 65-80, 11. 3 coming back with 4,000 8 foot wide trailer at 62. Speed control all the way home and I don't think it was up or down 1 mph including a long 6% pull. This was via the overhead as the pumps kept shutting off at $100 and I wasn't that interested in hand calculating. It shifted some, but left it in drive and no tow haul. I thought the towing mileage might be slightly higher, but in this case I think frontal area is more of a factor than the weight. Truck had 800 miles on it when I left. It was about 650 miles round trip. I have to say it was very impressive towing, even if it wasn't anywhere near its limits.

 

[RVTRKN]

I made a run to upper Indiana to pick up a new travel trailer in my 13 2500. Unloaded going up I was impressed with the mileage as it was in the 20-22 range averaging between 70-80 mph. Coming back with the TT, mileage went to 7-9. This was with a TT that was around 8000 pounds and the average speed was between 65-72 mph. Also, the truck seemed to struggle with the weight a bit and kicked down a lot. Im not a troll, and I absolutely love the truck. It just seemed that my unmodified 05 handled that much weight better and didn't kick down hardly at all with the same kind of weight. The trucks were very comparable other than the figures(610 torque 3:73 gears 4 speed auto vs. 800 torque 3:42 gears 6 speed auto). Was I expecting too much?

Thats the argument I used when the 3:42 was discussed on another thread. Ya, your going to save money empty, but when loaded, it will be like climbing a perpetual grade, not to mention they will wear out sooner. I've always been disappointed with my MPG, empty or loaded, with my C&C but the 3:73 has helped a bit, and I think if I had the 4:10's my MPG would be much better towing or not. The truck weighs almost 10K empty so its like running loaded all the time.

 

[NIsaacs]

Was I expecting too much?

There are a lot of variables when comparing fuel mileage. One of the biggest is the elevation of point a and b. Indiana's elevation is less than Oklahoma, so empty you were going down hill overall and loaded you were climbing overall. If you made the same trip in reverse your mileage would change by about 2 mpg. Mileage would be about 18-20 empty and 9-11 loaded.



Nick

 

[EDankievitch]

I had found with my 05 that if you drove and kept the exaust temp below 650/700 degrees I would get much better Mpg's than if I shifted up and lugged the engine. The 13's with the 3. 42 gears really lug the engine. Even at 65-70 mph. I would not be surprised if you found the exaust temp when towing to be over 950/1000. Give down shifting a try I bet you'll see better mpg's.

 

[RustyJC]

17 MPG running empty on the Interstate at 75 MPH, 9. 5 to 10. 5 MPG towing our 16,000 lb GVWR 8. 5' wide 13'2" tall 5th wheel on the Interstate at 62 MPH in 6th gear. That's with a box stock 2011 350/650 dually with 4. 10 gears, 68RFE and all the smog gear intact. 3. 42 gears for towing with a double overdrive transmission? No, thanks!



Rusty

 

[dpatt67]

The wind both directions was almost non-existent, but was slightly against my favor coming south. I agree about the 3:42's, they're great empty(which will be most of the time), but not optimal towing especially with a large frontal area. If I were towing a lot I would at least spring for the 3:73's. Mine does have the slight flare in rpm's, but it's not too noticeable. I will do what some of you have suggested and leave it in fifth, especially in any hilly areas. I appreciate all the comments and hints. This is my 3rd Ram diesel and all have been great. To be honest, I think I just got caught up in the idea of "800 ft lbs of torque" and ignored the fact that this truck weighs more, has higher gears, and trailer weight and frontal area still the robbers of power. .

 

[EDankievitch]

Nice thing about having tall gears is you can always down shift... .