Duramax Owners-Gear Question

[Cajun Po-Boy]

When towing with the Duramax, we simply put it into drive, engage Tow/Haul button and mosey down the road.

Question-When do y'all move your shifter to third gear when towing and what was the reason to drop it in third and what was your speed and/or rpm levels?

This is just a generic question...was on my mind and thought to ask

[AquaMan]

I put mine in drive and never drop it into any other gear unless I'm decending a hill, and even then, the engine brake usually takes care of it for me. There is no need to ever shift your Allison transmission during normal operation.

[crasher]

Yes, you only want to shift manually if you want to increase rpms for some reason. Could be helpful in hilly terrain if the transmission is not downshifting to suit you, or it's hunting around for a gear.

I've never had that problem, as the auto does a good job. Generally don't use the tow/haul mode unless I'm heavily loaded (75% of max) and want to run at higher rpm. Also I engage the exhaust brake if in steep hills or in heavy traffic (urban areas).

[h20ski]

Here is how my manual reads page 424:

• If you have an automatic transmission, you can tow in DRIVE (D). You may want to
shift the transmission to THIRD (3) or, if necessary, a lower gear selection if the
transmission shifts too often, such as under heavy loads and/or hilly conditions. If you have a manual transmission and you are towing a trailer, it’s better not to use the highest gear. See Tow/Haul Mode Light on page 262.

Tow/Haul Mode

Tow/Haul is a feature on automatic transmission equipped vehicles that assists when pulling a heavy trailer or a large or heavy load. See Tow/Haul Mode on page 147 for more information. Tow/Haul is designed to be most effective when the vehicle and trailer combined weight is at least 75% of the vehicle’s Gross Combined Weight
Rating (GCWR). See “Weight of the Trailer” later in the section. Tow/Haul is most useful under the following driving conditions:

• When pulling a heavy trailer or a large or heavy load through rolling terrain.

• When pulling a heavy trailer or a large or heavy load in stop and go traffic.

• When pulling a heavy trailer or a large or heavy load in busy parking lots where
improved low speed control of the vehicle is desired.

Operating the vehicle in Tow/Haul when lightly loaded or with no trailer at all will not cause damage. However, there is no benefit to the selection of Tow/Haul when the vehicle is unloaded. Such a selection when unloaded may result in unpleasant engine and transmission

[tomjsas]

like those above I put it in drive with two/haul on and don't do anything else.

[Herk7769]

I also have the Alison and I put it in tow/haul and drive.
It is always in the proper gear up or down hill.

The only time I reset it is on level highway and in cruise. If the transmission has not shifted into overdrive on its own due to the cruise speed, I punch it off; then back on after it upshifts.

[DeeMax]

Ditto. No reason to shift. Occasionally will remove overdrive in certain conditions, but that's rare.

[FR28footer]

Put mine in drive. Always use tow/haul mode and exhaust brake on. Pulling a 13k trailer I like the help the truck offers.

[Chuckinca]

My Dodge manual says to use tow/haul when towing or hauling. I don't use it unless it's hilly or windy. I'm probably about 73% of Gross Wt. TT about 6.7k, empty truck 7.4K, truck load 1.2K = 15.3K/21k.

Don't know where tongue wt figures into all that (the truck can handle another 1k load).

It usually runs fine on the flat without tow/haul -

(somebody with a 13K trailer must be nearly at 100% gross)

I saw a guy with my truck model at a rest stop South of Raton Pass with a huge 5er - he said it weighed 14.5K. I mentioned it was over the recommended max weight and he said it wasn't an issue with the 1 ton diesels.

.

[FR28footer]

Originally Posted by Chuckinca

(somebody with a 13K trailer must be nearly at 100% gross)

.

Nope. You should pull the truck specs. before you throw out opinions.
I used the weight calculator, truck and trailer specs to make sure I still have a good safety margin. Plus it is not a Dodge.

[AquaMan]

Originally Posted by FR28footer

Nope. You should pull the truck specs. before you throw out opinions.
I used the weight calculator, truck and trailer specs to make sure I still have a good safety margin. Plus it is not a Dodge.

I think he was referring to same Dodge setup as his truck. At least that's how I took it.

[Helmsey]

Originally Posted by DeeMax

Ditto. No reason to shift. Occasionally will remove overdrive in certain conditions, but that's rare.

+1
If on the interstate I will press tow\haul once to engage it, set cruise control and drive. If on a 2 lane or slower moving traffic on interstate I will hit the tow\haul button and hold it and that will lock out overdrive. Seems to keep the RPM's in a better spot while running around 50MPH.

[whj77372]

13,000 lb fiver plus 7,500 lb truck plus the 2,500 lb pin weight is 23,000 lbs that is the GCWR for my 2011, F250, CC, diesel, longbed, RWD. If the truck is older it should be less.

[FR28footer]

Originally Posted by ttrost65

I think he was referring to same Dodge setup as his truck. At least that's how I took it.

Oh.........thought he was referring to my post. Also thought this was a Duramax question.

[fschambe]

Originally Posted by herk7769

I also have the Alison and I put it in tow/haul and drive.
It is always in the proper gear up or down hill.

The only time I reset it is on level highway and in cruise. If the transmission has not shifted into overdrive on its own due to the cruise speed, I punch it off; then back on after it upshifts.

Listen to this man he knows what he is saying!

I do the same.

If you have the exhaust brake and keep it in tow mode with exhaust brake engaged you probably won't even need to use brakes going down hill.

[AquaMan]

The engine brake is the greatest. Most of the time when coming to a stop, I'm just resting my foot on the brake pedal enough to activate the brake lights, the engine brake does all the slowing down.

[Herk7769]

Originally Posted by fschambe

Listen to this man he knows what he is saying!

I do the same.

If you have the exhaust brake and keep it in tow mode with exhaust brake engaged you probably won't even need to use brakes going down hill.

Is your exhaust brake aftermarket or standard on the 2012?

[AquaMan]

It's standard on 2011 & 2012. It can only be engaged when the tow/haul mode is engaged, and seems to be somewhat variable depending on braking. That could be just my imagination though.

[Herk7769]

I wonder if it is possible to retrofit it on the 2008...

[TURBS]

Originally Posted by herk7769

I wonder if it is possible to retrofit it on the 2008...

You can get an aftermarket exhaust brake from www.bullydog.com and other performance diesel companies.

Turbs