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Did Some Towing With My 2500hd Gasser Today For The First Time

phillyturbosix

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phillyturbosix Enthusiast

phillyturbosix

Posted
Posted

Truck is a monster in tow/haul mode for sure! It was the hottest day of the year here in Philadelphia. It was at the hottest 104 degrees outside. Ice cold in the truck! :) The truck temps never moved from 210 the entire time. The trans temps got up to 200 at one point but mostly stayed around 190 to 196 the entire time. A lot of stop and go traffic with the AC blasting no less. I only used a half tank towing but it looks like the truck was getting around 9.5 MPG. Next week I'm hauling the trailer out to Ohio so it will be a real test to see. While I did not get around to installing the rear air bags yet, After pulling the truck does not really need them but when you hit those dips in the highway it was a little bouncy. I know the air bags will cure that. Going to have them installed tomorrow before my haul to Ohio. The tow/haul mode is amazing. They really did their research and the trans worked great. It honestly took maybe a half hour of driving and the truck learned my driving ways and learned how to handle the trailer. After that she worked like she should and did a great job of it! Here are a few shots of truck and trailer.... :sigh: I love this truck!

 

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uh6tdrvr Enthusiast

uh6tdrvr

Posted
Posted

Nice truck and TA! For comparison, what mileage do you usually get driving w/o the trailer?

phillyturbosix Enthusiast

phillyturbosix

Posted
  • Author
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Thanks guys! I typically see around 13 to 16 MPG with the truck. But I'm mostly city driving. Never really had it on the road yet. I'm in the NE area of Philly so it's not totally city driving but not highway either. I figured it would be around 10 to 12 hauling. Heading to Ohio with the car next weekend so I'll report back my mileage for sure!

Bear68 Enthusiast

Bear68

Posted
Posted

See my post under towing, but I just returned from a 2,000 mile trip pulling our camper which is around 8,000lbs loaded plus all six of us in the truck, and truck bed loaded with bikes and other gear. The Sierra performed very well!! I normally get 12 mpg when not pulling and when I am pulling the camper and on this trip I averaged 8mpg... I noticed when I was trying to maintain 70 mph, the RPMs were around 3-3.5...is this normal? I figured pulling this kind of weight at this speed the motor was working hard. When I backed her down to 65 mph, the RPMs reduced to 2.5.

 

Nice truck by the way and you get great mileage driving in Philly!

Doug_Scott Senior Enthusiast

Doug_Scott

Posted
Posted

You may want to look into getting a "bubble" for the front of the trailer. That will help mileage and improve handling when pulling the trailer. There are bubbles you can get that attach to the front face of the trailer that really help the air flow around the flat face of the trailer. You can also put a big "V" on the front of trailer. Basically close in the nose of the trailer from the hitch ball to the leading edge of the actual trailer body, following the trailer frame.

beck@becksystems.com Enthusiast

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Posted
Posted

I have a 2005 2500HD Crew Cab, 2WD. Pulling a 6500 lb enclosed car hauler with V-Nose. At 70 mph I get 9.5 to 10 at most. Without the trailer - it gets about 13.5 to 14 highway driving at 65-70 mph. In town, stop and go - about 11 mpg.

 

The V-Nose does "seem" to be more stable in cross winds and passing 18 wheelers etc.

 

So far - I have not seen any controlled experiments that prove either a bubble nose or V-Nose increase mileage by any significant amount. Would be great to see some properly conducted Wind Tunnel results / comparisons done by an independent third party.

 

To increase mileage - you have to reduce drag. Pulling a enclosed trailer behind a Pick-up - that would mean using a lighter trailer, that is lower in height than the typical 6' and narrower than the typical 8.5'

 

This one at least makes sense from a weight and aerodynamic perspective. Although a bit pricey.

 

http://www.bre2.net/mm5/merchant.mvc?Scree...de=car_trailers

 

FWIW,

Carl B.

Doug_Scott Senior Enthusiast

Doug_Scott

Posted
Posted

The reason I mentioned it was my buddy has a 05 Sierra ExtCab with a 5.3/4spd with 3.23 2wd. He purchased a 7x14 enclosed motorcycle trailer that had a flat front on it. His first trip with the trailer and with 2 Ducati race bikes on board and full pit equipment for the 2 amateur class bikes yielded him somewhere around 7-9 mpg (canadian gallon) that he found to be poor. He invested in a bubble and attached it to the front of the trailer. The following season, on the same trip to Mt Tremblant in Quebec, he got somewhere close to 12mpg. Trailer was also a lot nicer to pull, and the "tail wagging the dog" feeling was gone. The bubble was approx 18 inches deep.

beck@becksystems.com Enthusiast

[email protected]

Posted
Posted

Hi Doug:

It would be interesting to me - to see a picture of your friends truck/trailer ... Moving from 9 to 12 mpg is a 33% increase in fuel efficiency. Most "aero-devices" claim at most a 10% improvement.

 

I will most likely be building a custom trailer to haul my cars this comming year. I plan to get the total height of the trailer down to around 63" from the ground to the top of the trailer. {it will be a "Pop-Top" trailer - so I can pop the top up when loading/unloading} Air suspension will lower the trailer for Freeway travel as well. I only need about 55" inside the trailer for my cars. I'm still working on finding the most effective way to gain the best shape for the front of the trailer... and a bubble just may be the way to go..

 

FWIW,

Carl B.

Darth_Sidious Enthusiast

Darth_Sidious

Posted
Posted

You saying you love Tow/Haul mode has made me wonder. Did you hit many hills? I tow an 8.5x20 enclosed as well. In the WV mountains, I hate T/H. For example there is a hill I go down everyday fully loaded to around 8k. It is a 4lane highway with the speed limit 65. I'm going about 67 and at the base there is a curve that I need to slow down to 60 or so or my load will slide. It just takes a couple taps of my brake to get to the point. If I have T/H on, the thing downshifts super hard to slow it down. Super annoying.

 

Even if I let my foot off the gas to coast going down a hill, but don't hit the brake, it still thinks I want to slow down.

 

I've put 10k miles towing on it since Feb and maybe 1k have been with T/H on. How do you handle those situations?

jandersinc Enthusiast

jandersinc

Posted
Posted

I hate the tow / haul mode and very rarely use it. I hate the hard super high revving downshifts too. The gas engine doesn't have enough compression braking to slow my truck and 9,000 pound boat so all it does is downshift and run it at 4500 RPM.

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