Exhaust brake and Tow/Haul mode

[WillRoach]

Any one else notice a difference on how the exhaust brake works with the Tow/Haul mode is turned on? My truck seems to slow alot faster and the exhaust brake stays engaged at lower RPM's then when the tow/haul mode is on. When it is off all i get is some noise coming from the turbo and very little braking action unless i am at higher speeds.



Will

 

[Jim W]

Yes, this is correct. The Tow/Haul mode has a more of an aggressive braking with the exhaust brake and the shift points are changed. I also believe that the ECM runs a different program when the Tow/Haul mode is engaged. I think the engine exhaust braking is set to engage faster and stay engaged to a lower RPM for additional braking.

I know this helps with slowing the truck and 5er sooner then with out the exhaust brake engaged.

 

[2 Ram Fam]

Sounds right, same here.

 

[RDHamill]

I believe that with "Tow Haul" on, the truck has a "zero throttle downshift" feature.

When you lift off the throttle it starts a sequence of downshifting with the Exhaust Brake applied. It is very effective for slowing on freeway off ramps. I was less pleased with it while driving in hilly country where I'd like to just lift off the throttle and roll freely down the hill.

 

[WillRoach]

Thanks everyone for helping me understand!



Will

 

[HBarlow]

In Tow/Haul the automatic transmission is downshifted to fourth then down to third gear when you back off the throttle and slow and the exhaust brake will remain activated down to approximately 20 mph.

Following each downshift your engine runs at a higher rpm which provides greater exhaust braking. Watch the tach and feel the downshifts and you will realize what the computer is doing for you.

 

[PatrickMarshall]

The one thing I like about having the Tow/Haul mode on with the exhaust brake is when I use the cruise control. It's nice how the exhaust brake works with the cruise control, slightly feathering the speed on downhills to keep the speed constant.

 

[WRStrong]

Ditto on everyone's replies. One thing I don't like is the harsh downshifts with exhaust brake and even harsher with exhaust brake and tow/haul mode when empty. I guess the obvious lesson is don't use tow haul when empty.

 

[HBarlow]

Exhaust braking in Tow/Haul mode is great when towing a heavy trailer but does tend to brake pretty hard when unloaded. I use mine all the time whether towing or not but all three of my Dodge Rams have had an exhaust brake from day one so I guess I don't really notice it much.