Tow Haul Mode, W/5th Wheel

[smd]

`05 48r AUTO 3500 STOCK TOWING 12500 5TH, in Reno Area.



In the past I towed a 4500lbs Coleman Tent trailer, CTD didn`t know it was there. I just bought a Montana 5th that is 12500lbs.

So I`ve read here where you should down shift into 2nd on a steep down hill grade. Then somefolks said don`t down shift, its to hard on the auto transmission and it would rev too high. Then I`ve seen many people writing about down shifting and using the tow/haul mode. What is the proper sequence/usage in towing on a 8-4% down grade in the Sierra`s. I`m truly confused ... A good bench mark to start would be helpful. And thanks to all in this forum! Mark

 

[dzldpatriot]

Our 5er is not quite as heavy as yours, nor do I have those grades around where I live... . but, when pulling the camper I just put in the tow/haul mode and leave it. Have had no problems.

 

[Dieselnerd]

Ditto on the Tow/Haul. I just put it in Tow/Haul and leave it while I'm towing. It doesn't lock out overdrive and changes the shift points so it's easy to get rolling from a stop. Different than prior to 2005 model year, then Tow/Haul locked out OD.

 

[thomase]

I've also got the 05 DRW w/ auto and I haul a heavy gooseneck around. I just put it in tow / haul and go. It seems to handle everything well. Also make sure the brakes on your 5th wheel and your controller are in excellent condition.

 

[bigbob7777]

So, how does the tow/haul know you want to go downhill at 45MPH, for example? Are you supposed to tap the brake or something? Please clear this up for me.



Also, if you have the cruise set at 45, if you tap the brake, doesn't that take it out of cruise? I have the 2005 3500, DRW, 3. 73, auto.



bob

 

[BrianWood]

Hey, Bob... I tow a slightly smaller 5th wheel with a 2005 2500 auto. Here are a few tips I've learned:

1. When you hit a long grade, tap the Tow/Haul to OFF, wait a quick second, then tap it back to ON. The transmission will downshift out of overdrive and help hold you back on the hill. If you hit the go pedal, it will shift back in to O/D. A great way to get in to 3rd and hold it there since there is no "3" on the shift lever.

2. If you need to go slower than about 40 MPH, you can downshift into 2nd... if the revs get a little too high for comfort, stab the brakes to get your speed down.

3. Don't ride the brakes! Firm, even pressure, get 5-10 MPH below the speed you want and then let off.

4. Slow and alive is better than fast and dead!



Have fun!

 

[bigbob7777]

Thanks Brian. Excellent advice.



bob

 

[Dieselnerd]

When in Tow/Haul mine downshifts going downhill when I step on the brakes. My understanding is it's supposed to work that way. Not quite the same as an Allison but better than the 47RE was.

 

[smd]

Great tips Thank you!

 

[JGrosso]

When Towing, I use the tow/haul mode, but it dosen't allways down shift when I want when decending hills, but if you tap the tow/haul mode back to auto, then back into tow/haul it usually will down shift. An exhaust brake would help, but I don't tow that often, so it's not worth it for me to install one.