Opinion/Experience with Smart Brake Function of Exhaust Brake

Friends,

I'm starting this thread to solicit opinions and experiences with the Smart Brake (SB) function of the EB. Just for everyone's info, it is activated by depressing EB function button twice... selecting EB button once lights amber EB light on dash, selecting a second time gets a green EB light on the dash. I personally prefer Normal or Full EB mode... Its seems that with SB function on and cruise control on, speed actually increases some on downgrades. Maybe I'll play with it some to see if it's better solo, than towing.

Here's from the 2017 Diesel Supplement:

DIESEL EXHAUST BRAKE (ENGINE BRAKING) The purpose of the exhaust brake (engine braking) feature is to supply negative (braking) torque from the engine. Typically, the engine braking is used for, but not limited to, vehicle towing applications where vehicle braking can be achieved by the internal engine power, thereby sparing the mechanical brakes of the vehicle. Benefits of the exhaust brake are: • Vehicle driving control. • Reduced brake fade. • Longer brake life. • Faster cab warm-up. The exhaust brake feature will only function when the driver toggles it on by pushing the exhaust brake button until the Exhaust Brake Indicator is illuminated. Normal (Full Strength) exhaust brake mode is indicated by a yellow Exhaust Brake Indicator. Once the Exhaust Brake Indicator” is illuminated and the vehicle is moving faster than 5 mph (8 km/h); the exhaust brake will automatically operate when the driver removes pressure from the accelerator pedal. Exhaust braking is most effective when the engine RPM is higher. The automatic transmission will downshift more aggressively in TOW/HAUL mode when the exhaust brake is enabled to increase brake performance.

CAUTION! Use of aftermarket exhaust brakes is not recommended and could lead to engine damage WARNING! Do not use the exhaust brake feature when driving in icy or slippery conditions as the increased engine braking can cause the rear wheels to slide and the vehicle to swing around with the possible loss of vehicle control, which may cause an accident possibly resulting in personal injury or death.

NOTE: For optimum braking power it is recommended to use the exhaust brake while in TOW/HAUL mode. The exhaust brake feature can also be used to reduce the engine warm up time. To use the exhaust brake as a warm-up device, the vehicle must be stopped or moving less than 5 mph (8 km/h), the Exhaust Brake Indicator must be on, and the coolant temperature must be below 180°F (82°C) and ambient temperature below 60°F (16°C).

Automatic Smart Exhaust Brake (Auto) Automatic Exhaust Brake technology delivers smoother, less aggressive exhaust braking characteristics during downhill descents. Although it can apply full exhaust braking force if needed, Automatic Exhaust Brake may not apply obvious braking if the vehicle speed is not increasing. Automatic Exhaust Brake is intended to maintain vehicle speed, while Full Exhaust Brake is intended to reduce vehicle speed. Automatic Exhaust Brake can be enabled by pushing the exhaust brake button again anytime after the normal Full Exhaust Brake has been turned on. The “Exhaust Brake Indicator” in the instrument cluster display will change from Yellow to Green when Automatic Exhaust Brake is enabled. Pushing the exhaust brake button again will toggle the exhaust brake mode to off.​

Anyhoo, real interested in hearing feedback on this.

 

Tried auto a couple times and didn't like it. Didn't give much braking and the Cruise would do that same thing if the brake was in full on mode anyway.

 

I will use Auto from time to time if I know I want to be able to coast a while, but 98% of the time it's full brake. I'd much prefer if it was set up like a real Jake with a separate On/Off switch, and 2 or 3 retarding levels, and with the switches or buttons on the wheel, or on a column stalk. I think the current location at the bottom of the center stack is asinine.

 

I use auto all the time. It's really handy when driving in rolling hills since it remembers the speed in which you take your foot off the throttle and will activate above that speed, or if you touch the brakes.

I have not found any difference in FULL/AUTO when using cruise control as both allow about a 5 mph increase over the set speed before engaging, which I find ridiculous.

I have also not found that it does not apply less than full power when applied, simply that it will modulate to maintain speed when not in cruise control unlike FULL which always works to slow you down.

So depending on how/where I am driving I will use both.

 

I tend to use auto when on speed control in the mountains as it does hold the speed close to the set speed.

My biggest problem on my 2018 is in full on mode the brake will not activate until I get above 30 mph, then slow down. I have had quite a few situations in the mountains towing when because of the tight turns I could not get above 30 so the brake would work the first time. At that point I do not have the benefit of the exhaust brake and have to use the truck brakes all the time. I can't find any data in wi-TECH that details desired brake operation vs. actual.

 

Full on here. Don't care for auto. I like the brake coming on as soon as I let off the throttle. I also always run in tow/haul mode for more braking.


Earl

 

I like auto EB in certain conditions. It really does well on secondary roads that are hilly and curvy in nature, especially the heavier the load. Sometimes with the EB on full on it just tends to take all your momentum away in the above circumstances which makes the truck work that much harder. This can be negated with just a slight touch of the throttle to keep the EB from engaging but IMO that's just one more thing to think about and the auto EB takes all this into consideration. The same thing can be accomplished with both programs but the auto just makes it easier sometimes.
It really does depend on the situation. When not towing I do tend to leave it on full on more often than not.

 

Actually I have found that the EB tends to be more aggressive in the auto mode in certain conditions as it is trying to maintain a certain speed and the further you get away from the last known speed the more aggressive the brake becomes.

 

I use Full mode all the time. You can easily modify and get used to your driving style to accommodate the program. I didn’t like the Auto’s version of you have to be X amount above a certain speed or your foot on the brake to make it activate. Full is predictable everytime in every scenario. It’s what I use.

I did learn more about Auto and the temp variable that allows EB during warmup thanks to this thread. It makes sense now. Still doesn’t explain my delayed first time use problem I’m experiencing, but it makes sense.

I can tell you this, mine has a RPM limiter, not so much a low speed permissive. Anything below 1100 RPM and it drops out or won’t activate, which also makes sense. When TH is active, it keeps the RPM up higher which makes the EB more effective. Once you’re below 1100, it drops out. It doesn’t seem to be speed sensitive. If it is, you can’t really detect it.

So for my driving and use, Full all the time, TH as needed. 4:10 Aisin, that probably also adds to the variables as well.


Your mileage may vary....

 

So, from what everyone is saying, sounds like

- SM working without cruise control, allows you to coast (take foot off accelerator) without engaging unless you are accelerating past the last speed set by the accelerator, and functions like normal EB when you touch the brakes. That's cool.

- SM with cruise control on is LESS aggressive initially than normal EB when truck is accelerating down a hill past set speed, and progressively gets stronger the more past that set speed it accelerates until it applies full EB to slow down

- Normal EB with cruise control is MORE aggressive (full EB) initially when truck is accelerating down a hill until set speed is restored.

I may start using SM now that I THINK I understand how it functions. Let me know if I missed any of the assumptions above.

Thanks, Ron

 

As I have said here before, I use full almost all the time, however, if I am towing and descending a steep grade with lots of turns, I find Auto works much better as there is a lot less upshifting and therefore less downshifting that isn't necessary and makes for a jerky ride which I can't help but think is not good for the drivetrain. Further, in the above scenario with full EB, the need to use the brakes is almost non-existent, therefore the entire stopping force comes down to one set of tires, shafts and ring and pinion. While I understand it is designed for that type of load, I like that in Auto, I can also use the brakes and have all 8 wheels on the ground contribute to slowing the load.

 

I could not agree more on all points. And who ever designed the dash layout should be taken out back and flogged.... Why on earth would you put the EB / TH buttons at the bottom center of the console/dash? Every time I use it I have to look away from the road and try to press the correct small button that happens to be right above the small aux switches.... Many times inadvertently turning on an AUX switch instead. I have an unrelated gripe is with the 12" etch-a-skecth display.... I listen to close near all types of music except hip hop so... I constantly adjust the Bass Mid Hi controls, Why on earth when I press the "Audio" button does it open with the Balance/Fader page instead of the equalizer control page?? I then have to take my eyes off the road again to press equalizer... Too bad they don't allow you to customize the page layout and put stuff where you want it. Other than that.... I sure love my 19'.... Just turned 10,500 on the clock.

 

JMHO but I like the auto mode. As has been mentioned I can coast awhile without the brake coming full on. Just a tap on the brake pedal engages it. Seems to be not as jerky as full on with the 4:10 gearing. I too agree on the switch location but am getting used to feeling for it. I now know its the second from the left on my truck after alt. trailer height. One thing I do love about this truck is the ease with which it tows thru town. My 06 towed fine once up to speed but I almost dreaded hooking up. Not with the 19.

 

Friends,

Just got back from driving country, curvy, two lane road 60 MPH speed limit to pick up some paint for my LRE engine; on the way there, I used SB setting and it worked well. Shut truck down and when I restarted, it remembered it was in SB mode.

On the way home, I decided to put back full EB, and realized the driving style I use. I run with foot on the throttle at desired speed and when I need to slow, I feather the throttle, if I want to slow faster I release throttle with foot lightly on it. This way, I can slow with throttle, increase slowing down engaging full EB without touching the brake pedal, then If I want to go slower or stop, apply the brakes. I do this instinctively because I installed a BD EB on my 00 and 02 3500, both with 5600 6spd manuals, had a on/off switch on the shifter, but learned to feather the throttle to coast, with our without the EB. There was a little micro switch with the BD EB that activated it when you released the throttle.

Nothing wrong with using SB or full EB as it's personal preference how to use them. Me, I still like the old way I learned on my two former 2nd Gens.

Thanks for all the posts, very enlightening, and looking for more shared experiences.

Cheers, Ron

 

Ron, Auto and Full are what I find most folks call them. SB wasn’t even something I recall seeing until this thread. The truck calls it Auto and Full so I follow suit.

I did have to change my driving style a little from my 05 that only had “Full”, but the coasting ability is well worth the learning curve for certain driving, IMO.

 

You are correct on the abbreviated name... this is from the FOM "Automatic Smart Exhaust Brake (Auto)" I cued on Smart instead of Auto. I guess after driving 9 years with the 02, 9 years with the 09, and now 2 years with the 17, I'm pretty well dialed in to feathering the throttle and engaging the Full EB without touching the service brakes. Even in Auto, I was doing that, and do that on all the vehicles I drive. I may figure out sometime the utility for me to use Auto.

EDIT: Did you fly or maintain Apaches? I friend of mine flew drug interdiction in one... got shot at several times.

Thanks for the info.

Cheers, Ron

 

@Ron, your experience with auto is why I didn't like it. I hate having to use brakes to get it to work.

 

That’s where it just depends on the road conditions. For every time I can think of where I dislike having to touch the brakes to engage the EB there is a time where I hate that I have to feather the throttle to coast. It’s actually quite nice that they gave us both options.

I flew Apache’s from 06 to 16. Worked my way from a basic pilot/gunner to a maintenance test pilot in both A/D Apache’s and a maintenance test pilot evaluator in the 64D.

The army did some restructuring in 16 and now we’re flying blackhawks. I’m doing both maintenance test pilot and maintenance test pilot evaluator duties in A/L/M 60’s. We’re just switching to the 60M and I picked one up in NJ last week and brought it back to ID. Quite the aircraft.

 

I couldn't agree more. I had to haul a draper head last night and was thinking about this. On flat ground, particularly long stretches where it's easy to maintain speed I typically do use the full EB more often. If I let off the throttle it's more likely because I need to slow down, not necessarily coast. It really does depend on the situation.

OK John, inquiring minds would like to know. How long of a flight was that from NJ to ID? How many stops? If you can't get into specifics I understand. Just a redneck country boy being nosy

 

If it had an On/Off switch we wouldn't have to feather the throttle