I'll begin with what I have been led to believe. Then I hope someone out there in Super Duty cyber land can correct or update that.

I have been led to think that the 2015 model (mine) was the first to have the exhaust brake. Most of my driving is with a 30' travel trailer (8k) in tow and I use it and like it. The truck I traded for this was an '06 Dodge 3500 w/Cummins and no exhaust brake. My son has an '09 Cummins with exhaust brake and it seems, at least to me, that the exhaust brake on the Cummins works more aggressive than my ford. Recently on this forum I was reading an old thread explaining how the ford system works by using the exhaust brake along with the transmission to apply necessary braking on downgrades AND it works both with tow/haul and without and is applied as a factor of brake application.

I use it and like it but I just think it should be applied more aggressively before the transmission downshift is engaged. I also have found that on those long downgrades when the cruise control in in play that it allows the speed to overrun the CC selected speed by 5-8mph before the truck will aggressively begin to downshift and bring it back into the selected speed. Most of the time this is OK and reasonable but sometimes (mostly on smaller highways) I would prefer to see it not override quite so much. In those cases I kick the CC off and do it the old fashioned way.

Thanks all. See ya down the road sometime.

Roger from sunny and warm ( finally ) New Jersey

 

The 2015 was the first year that had a button for you to push to activate the EB. All 6.7L engines had exhaust braking, Just no button. The 2011-2014 engines had a smaller turbo, hence less back pressure for braking. So the 2015 have a stronger Exhaust Brake than earlier 6.7L engines.

The Dodge Cummins engines have stronger ( stiffer) exhaust valve springs, Hence they can tolerate higher back pressure than the Powerstroke. Producing more braking power. The Powerstroke exhaust braking will never be as strong as the Dodge.

In previous after market exhaust braking, you had a butterfly valve that created pressure and you had a waste gate that dumped excess pressure if the back pressure got to high. With the newer engines, Back pressure is created by the variable vanes in the turbo. This is all controlled by the trucks computer. So you are not going to change this unless you can change or bypass the original programming.

The trick is to learn how to maximize the braking that is available. I used the exhaust braking a lot on my 2011 truck. Pulling a 13,000 lb horse trailer around the mountains of Utah and it worked just fine once I learned how to use it.

First off. Know that Exhaust braking is not going to slow you down. It is more effective at Holding a speed. So when I crest a summit with a load. I slow down to the speed I want to hold during the descent portion of the drive and set the cruise at that speed. That often means I slow to 50 mph at the summit, because I will see 50 mph curves down the canyon, I don't crest the summit at 70 mph and hope the EB can slow me to 50 mph, It will not do that. But the exhaust brake will hold my speed ( or withing the 5-6 mph of what I set)

Second, Know that Back Pressure is produced by engine RPM. You get much more exhaust braking at 3000 rpm than you will at 1700 rpm. Let the engine rev. If you are locking out gears, Choose the gear that gets the rpms up over 2500 rpm for better braking.

Play with it and you will learn how to get the most from it.

 

ThanX. That is the most comprehensive and clear explaination that I've gotten thus far. I appreciate your taking the time. I see your point about the RPM's driving the EB's effectiveness and will try that next time out. In my experience so far it's hard to tell just what's happening once the transmission begins to downshift with everything working simultaneously.

 

On my 2011, I played with it more. On my 2015, I just set the cruise, push the EB button and let the computers decide on what gear and what RPM.

I come down a lot of 7-8% grades. Depending on the speed limits, Some in 1st gear at 20 mph, some in 2nd gear at 40 mph and some in 3rd gear at 55 mph.

I don't really think about the EB if I can roll down a grade faster than 55 mph. I do find that the 2015 truck will hold my speed at 55-60 mph on 5-6-7% grades and stay in 4th or 5th gear. My trailers max out at 13,000 lbs, So if you have a heavier load, your experience may differ

 

Yes, even in the big rigs, with a Jacobs Engine Brake, AKA "Jake Brake", a down shift give two advantages.......more RPM=more braking power, and a better mechanical advantage!
Near where I live, there is a small city that coming in, there is a highway with a 6% downhill grade with a stop light at the bottom. When I am pulling either my 5er toy hauler loaded, or my gooseneck loaded, when I top the hill I do just like the big trucks.......start downshifting, as I decend the hill every time I can I shift down another gear and don't need to touch the service brakes until I am about 100 yards from the stop light. And yes, the engine brake in the Dodge is a bit stronger than in the Ford......just like the "Jake Brake" in a Detroit Diesel is quite a bit stronger than in a Cat Diesel.

 

OK, I think I'm beginning to get the ford EB system. BUT, I gather that it works on it's own whether the dash switch is on OR off. Does it function in a different way when in the tow/haul mode ?? So what is the purpose of the dash switch ???
Not a whole lot of steep grades here in NJ to practice on so gotta wait until our next outing.
Just trying to understand the ford way.

Thanks all

 

The Original 6.7L in the 2011-2014 trucks did not have a EB button. You just pushed the Tow/Haul button. Since dodge had a button, people called for one and Ford installed it in the 2015 model.

Basically pushing the tow/haul button on earlier trucks changed the shift patterns so you would stay in a gear longer.

To me the EB button does the same thing. Lets you stay in the gear long at higher RPMS so you get the back pressure.

For example. Lets say you are coming down a surface street with a slight down grade at 30 mph. In normal mode your truck will upshift to the highest gear to conserve fuel. You will be idling down the street in 4th or 5th gear at 1000 rpm. No real back pressure and no exhaust braking. But getting maximum fuel ecconomy.

With the Tow /Haul button or the EB button, your computer will tell the truck to downshift and still run 30 mph, but at 2000 rpm in 2nd or 3rd gear. This create some back pressure, with some braking to hold the speed even with 10,000 lbs trailer hooked up. It also keeps you in the power band, So if the traffic light you are approaching turns green and you can now accelerate to 40 mph, you have a more instant power vs lugging down or having to downshift. But your fuel mileage suffers.

I'm sure with the EB button pushed the computer is telling the turbo to close up and develop back pressure as much as possible and not to maximize fuel ecconomy. It's just how it manages the engine.

 

I notice a small difference when using the EB button or not. This is with TH on or off. I've played around with it on with a 1 mile long 10-13% downhill... TH makes the biggest difference and a tap on the brakes causes a downshift. Great, unless it happens to be icy/snowy out.

Like Jon, I had a 2011 as well and agree that the 2015 is much better than the 2011 was. Of course the 2011 was better than the 6.0 trucks and GM LMM/LML I had before that. I agree, Dodge's EB is stronger/better. None will overcome the laws of physics - start out too fast for your weight/vehicle and it won't be good. Notice that the 18-wheeler with the strongest EB isn't starting out 70 mph at the top of the hill either.

I will also add, Jon has driven 6.7 Fords more miles than I have, more miles towing, and more miles towing/driving in the mountains than I have too.

 

ThanX all for helping put this EB management into perspective for me. I am just trying to gain a better (but not too technical) understanding of how the EB/TH/ transmission all interface to manage things. It's a bit more clear now than MUD thanks to your responses.

ThanX all from sunny & warm New Jersey

Roger

 

I do not notice the exhaust brake do much of anything (on my '16) unless the EB button is pushed. Big difference with it on. Another step up with it in tow/haul.