towing 15,000 pounds with Duramax

[Critter81]

I am looking at towing 15,000 pounds with the 3500 Durmax DRW. It is a standard enclosed car hauler gooseneck. Does anyone have an estimate on my mileage? Can anyone tell me what they are getting towing with thier 5th wheel or gooseneck enclosed trialers

[MIKE WIENER]

I tow a 1200# fithwheel. I get between 10 to 12. It has a lot of frontal area it is 12'8 high. the hight of the trailer plays a big part in milage. I have a 01 3500 CCDRW DA. Hope this helps you get a idea of what to expect.

Mike

[David Utz]

With a 14,000 pound 5th wheel, I average 10 to 12 mpg. The worst was 7.8 mpg doing 75 with a strong head wind. On a trailer with lots of frontal area, "speed kills". Ten MPH slower can get you another mpg. It's not so much the weight, but the aerodynamic drag.

[djrogers]

Critter: I have a 2001 2500HD ext. short box and tow a 36' Holiday Rambler Presidential GVW#12400 we went to Florida last January from central Michigan traveling thru Ind. Kentucky, Tenn. and Ala. and upon arrival I totaled up miles driven and gallons of diesel used and averaged 11.8, My truck is equiped with a "Banks" system. So I am not lacking for horse power, my greatest concern is stopping, I prefer this truck as to a dulley for the manoverability and the MPG when not towing.Dave

[CaptainSir]

I too get between 10 and 12 mpg towing my gooseneck horse trailer. It usually weighs about 12,000 pounds. Headwinds really do make a difference.

On another note, technically speaking, with your 11,400 lb gvw on the truck and the 15,000 lb trailer, you need a commercial, Class A drivers license to legally drive the combination. Plus, again technically speaking, you need to have a formal commercial vehicle inspection on both truck & trailer. Lots of hassles I wasn't aware of when I bought my truck and trailer. Too bad the dealers don't tell you this but it's not in their best interest.

I tried lots of ways to get around the regs but was unsuccessful. Check with your state DOT for further info. My understanding is that many states are really starting to crack down on the whole commercial vehicle issue.

[Scuberboy]

I haul a 1992 27 foot Prowler 5th wheel with my 2004 2500HD Duramax 6.6 and 1000 series Allison. The trailer no where near loads the truck. The combination is UNBELIEVABLE. I love it. Fast, slow, up hill, down hill it doesn't matter this truck hauls it. Now I want to get a new trailer. Like everyone else I want all the trailer I can get. But still be safe. And I don't want to be a frieght train going down the highway. I want to pull with relative ease and not be nervous when I get to where Im going. As I shop for the new trailer I get different ideas on what I can and cannot pull. Wether it be the trailer dealer, GM dealer I get conflicting numbers. If I am figuring this correctly I have (Total)to use, 1700 lbs which is king pin weight and me (all load) in the truck. So the way I have been calculating it is to allow 700 pounds inside the truck/bed and 1000 pounds on the king pin. As I do this many of the trailers become "out of limits" as most are 1100, 1200, and 1400 pounds. I then begin to look for spring stops, air bags, overloads assist items etc. MY question is "Is there a site where I can read how varous trailers weigh on the king pin etc." Or perhaps there is a simple rule of thumb as I look at these trailers I can pull my pocket calculator out and see what I can and cannot pull?
I have been taking the total weight of the trailer and looking to see if there is some way to get 10% to 15% ONLY on the king pin. The manufactors do not want to discuss much of this. When I ask "How much weight is on the king pin" The dealer say's "You need to ask the manufacter about that but it is suposed to be around xxxxx" I don't want to know "about", I want to know exactly what IM doing. Any ideas are greatly appreciated. Reply here or on my personal email.
J.R.
LKFLNOW@hotmail.com

[richp]

On fuel economy, my 2001 K2500 with 90k miles has been right in the 10-12 MPG range its entire life when towing (which is about 2/3 of the time). Fuel quality, wind, temperature, but most of all speed are the determining factors in how much you get or don't get on fuel economy. I agree that you seem to lose about 1 MPG for every 10 mph over 55.

On the pin weight thing, you can get in the ballpark with formulas, but I would point out that in any case it is not a fixed number. For instance, I have a 40 gallon water tank at the very rear of my fifth wheel (a Jayco 32' with an actual weight on the scales of 11,500 pounds loaded for a long trip including a full fresh water tank). When full, that fresh water tank weighs 320 pounds -- which offsets a pretty large fraction of that amount on the pin. (Not all the 320 pounds is offset because the pin is farther forward of the axles than the tank is to the rear of the axles.) On the other hand, my waste water tanks are forward of the axles, so if I travel with them half full (which could be 3-400 hundred pounds of black and gray water) and the fresh water tank almost empty, I have more weight on the pin than advertized. See my point? Where you have food, water, personal effects, spare tire, dutch ovens, and all the tools in the storage bays will impact the pin weight.

Now, having said all that, my Jayco's actual pin weight was exactly 1,200 pounds the last time I weighed it (960# on the rear axle and 140# on the front axle). The trailer weight was 11,200#, so that is a shade less than 10 percent on the pin.

It's a tough nut to crack, but if you are really worried, then the ideal thing would be to get the dealer to take it to a scale and weigh the rig -- truck and trailer, axle by axle. And then weigh just the truck (both axles). With a little math, that will give you not not only the pin weight, but the actual weight of the trailer, which often is under-stated by the RV dealers. Then you have to work from there on whether your truck will have the flexibility in its capacity to handle that big a trailer.

For what it's worth.

Rich Phillips
Member #27

[Ed Hill]

I pull 36ft H.R. 5th wheel w/3500. Don't know weight of trailer - GVW is 14,400. Mileage usually ranges between 8 and 10 mpg.

[dmaxalliTech]

Hey djrogers! I see your from Ionia... I am in your neck of the woods, drop me an email and maybe we can hook up and talk shop someday
eric@gmdieseltech.com

[MWALKER]

I HAVE ABOUT 8000 MILES ON MY 04.5 DRW. MY 25FT FLAT BED HAS NOT LEFT THE TRUCK. I PULL 4000 POUNDS EMPTY TO AROUND 15,OOO POUNDS FULLY LOADER AND AVERAGE 10-12 MPG LOADED AND 15-16 MPG EMPTY.

[DMAXTER]

Our GCW was almost 22,000# on our last trip, 6,000 miles with about 1/2 in the Rockies, and our mileage ranged between 10 and 13 while pulling. We generally keep speed between 60 and 65 where the limit permits.

[Onebigcanuck]

My all up weight is almost 22,000, passengers, fuel, loaded trailer.

The worst milage I've ever gotten was 9 MPG pulling into a head wind all day, my best was 14 MPG during prolonged interstate travel in Idaho, Utah and Nevada.

I average about 60 MPH during a full day of driving.

My 2001 gave better mileage but the 5er I pulled was a lot lighter.

Anyway, I'm very happy with the truck & the mileage I get.

;)

[BozDMAX]

I have a 2003 K3500 Crew Cab DMAX pulling 15K# 34' HitchHiker 5th wheel (12'7" tall).

Driving around Florida at the moment and played around a bit with speeds one day (it was a LONG day) on some back roads and recorded the following:

mph mpg
45 13+
50 12-12.5
55 11.5-12.5
60 10.5-11

Temps were in the 70's, winds calm, alligators active. Hills? What hills?

Last June I pulled a 16,000# 28' Wells-Cargo gooseneck out to Seattle (from St Louis) and averaged 8-11 MPG, lower (the 8) in the Rockies.

64K miles in the last 2 years and I figure I just about broke even now on the extra cost of the diesel engine.

My mileage is about double my Father's Ford V-10 gasser. No wonder he has to sit at home ;)

Oh yeah, Banks Stinger package, with the big exhaust and exhaust brake (all self installed) and working well, thank you.

[dcalex]

Just for grins, I looked up the Calif. DMV regs on a commercial license.

A commercial vehicle is a motor vehicle or combination used for hire to transport passengers or A commercial vehicle is a motor vehicle or combination used for hire to transport passengers or property or which:

Has a gross vehicle weight rating (GVWR) of 26,001 pounds or more
Is designed, used, or maintained for carrying more than 10 passengers, including the driver
Tows a vehicle or trailer, which has a GVWR of 10,001 pounds or more
Transports hazardous materials, which requires placards
Tows any combination of two trailers or vehicle and trailer property or which:

[jaoder]

I have a 04 3500 DRW Crew Cab and I pull a 40' enclosed car trailer and it get 8-11 average depending on hills and wind.

[cos]

I consistantly pull a 19000# wedge car trailer and cruise at 70 to 75 mph getting about 9-9.5 mpg. If I slow it down to 60-65, I can get 10-10.5 mpg. Going through the mountains ive seen 7.5 mpg. This truck was made to tow a brick **** house - but it only likes sipping at 60mph. Mine is a 2004 with manual trans.

[Inspector]

Critter81:
The gross weight of my trailer is 15600. Ofcourse I never load it to that. I am usually around 13500 to 14000 road loaded. Emty weight is around 12500. I have been over the scales with a half tank of fuel,the wife and dog plus me at 21650. I will usually get between 9.5 and 11.5 miles per gal. I don't drive much over 70 mph. I have gotten 12 pulling the fiver.
I think that the most important thing to think about more than milage is safty. The Dmax will pull most anything hooked to it but is it safe to do it. I wouldn't recomend exceeding the manufactures specifcations. One needs to allow for safe braking and handleing. We all need to do what we need to do but keep safty in the back of your mind at all times while doing it..
Denny

[Mark-]

We just traded our 35' Jayco for a 37' HR Alumascape quad slide.

We got an average of 11mpg towing the Jayco from NH to AZ. Never lower than 9.5 (headwind and mountains) or higher than 13 on flat running observing the speed limits along the way.

The Jayco was 13500 GVWR, the HR is 14400 normally, but I opted for the 7k axles so the optional axles boosted that to 16900 lbs. I have yet (on the scales) to load heavier than 14k. I expect the mpg to be about the same as the height of the 2 fivers was the same 12' 7".

04.5 LLY 2500HD extended cab

I love this truck and that's from a lifelong Ford owner.

Mark