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zogg's avatar
zogg
Explorer
Jul 08, 2013

Just completed first tow....good and bad!,

As a newby, We just finished our first tow with a 2011 GMC hd 2500 6.0 gas from st louis, mo. to harrington beach campground north of Milwaukee, Ws. Trailer is about 8000 pounds. Trip was about 860 miles round trip.

Truck towed pretty well, but averaged 7.3 mpg....surprised, as I expected about 9-10....ouch.

Transmission in tow/ haul never went into 6th gear, and continually shifted from 5 th to 4 th and back as we went over tiny hills....maintained 65 mph for the whole trip. I tried taking it out of tow/haul, tried cruise control and no cruise control, and nothing seemed to make any difference in the way it shifted. I even tried manual mode in 5th gear but it still greaed down to 4th..

Had a little sway from time to time but nothing awful. The roads north of Milwaukee are awful rough, being concrete with constant ripples....beat me to death and shifted furniture in the trailer....

Does this all sound normal to those who are experienced?
Tow Vehicles

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  • goukcats's avatar
    goukcats
    Explorer
    Jul 08, 2013
    If you have a 4:10 rear, that's probably average. I did have an 08 CC SB 6.0 w/373. Pulling a 9.2k 5er, it got 8.2 to 9.2 consistently at 62 to 65 mph. I got 8.2 pulling in the TN & NC mountains & did use cruise on level & very gently rolling hills. I went to diesel mainly for the benefit of using cruise & hopefully better mileage. The diesel is a pleasure going up & down hills & I can use cruise 95% of the time (traffic permitting). It gets better mileage empty but unfortunately the towing mileage is almost identical.
  • Lantley's avatar
    Lantley
    Nomad
    Jul 08, 2013
    This is not meant as a bash but I think your experience is typical for a small block gas engine.
    Constant shifting,lower MPG, lots of driver input, not relaxing to me at all.

    What you describe is exactly why I prefer to tow with a diesel.
    Just for comparison sake see if you can tow your same trailer with a diesel.
    The experience will be enlightening and allow you to check out the night and day difference of gas vs. diesel.
    Many are content with your experience. Depending on how often and where you tow the gasser may be adequate. If you are happy and content with the towing you experience than all is well and you ignore my comments but if you are looking for better performance it is available.
  • rhagfo's avatar
    rhagfo
    Explorer III
    Jul 08, 2013
    Dick_B wrote:
    Sounds normal to me. We tow in Tow Haul mode and it works just like you described. 6th gear is non-existent in that mode.
    I normally get around 9 mpg towing at 56 mph. You might try slowing down for a trip to see if there is any difference in mpg.
    We find the engine is very noisy when under load.
    I long for my good old 8.1...

    Is that six speed a single OD or double OD? Can't see locking out sixth on flat land, that 6.0 should be ok in OD on flat land.
  • Dick_B's avatar
    Dick_B
    Explorer
    Jul 08, 2013
    Sounds normal to me. We tow in Tow Haul mode and it works just like you described. 6th gear is non-existent in that mode.
    I normally get around 9 mpg towing at 56 mph. You might try slowing down for a trip to see if there is any difference in mpg.
    We find the engine is very noisy when under load.
    I long for my good old 8.1...

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