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Exhaust Brake

7K views 60 replies 16 participants last post by  Tony Philbrook 
#1 ·
2019, 2500 4x4,towing a 25' travel trailer, The exhaust brake does not work in first gear no matter what the rpm's are. Does it work on anyone else's? Also this transmission seems to hunt 4-5-6 all the time in the hills towing. A lot of times it only holds 4 or 5 for only a split second, Can the dealer help that sort of thing? I frequently tow my trailer down a steep grade that is 5 miles long with a comfortable speed of 10-20 m.p.h. Just wondering.
 
#4 ·
Not in 1st gear it won’t.

If you have a 4wd use a front disconnect and utilize low range 2nd gear.
 
#3 ·
So you have an Auto?
No auto has a 1st gear TC lock up. So no exhaust brake in 1st.
5-6 hunting. Are you using tow haul? Lock out a gear if not.
 
#6 ·
No unless you have some custom transmission, there is no 1st lock up.
 
#8 ·
2019, 2500 4x4,towing a 25' travel trailer, The exhaust brake does not work in first gear no matter what the rpm's are. Does it work on anyone else's? Also this transmission seems to hunt 4-5-6 all the time in the hills towing. A lot of times it only holds 4 or 5 for only a split second,
Can the dealer help that sort of thing?
I frequently tow my trailer down a steep grade that is 5 miles long with a comfortable speed of 10-20 m.p.h. Just wondering.
Greetings @Riverside Jeep
I'm no mechanic but here's what I learned from CumminsForum.con about exhaust braking. . .

* Torque converter must be locked for exhaust brake to engage.

* If engine speed drops below 1100 RPM exhaust brake will disengage.

* When slowing from highway speeds expect exhaust brake to (finally) disengage at about 17 MPH.

* Obviously run with Tow/Haul mode on.

Note:
I read a post here on CumminsForum.com a few months ago that the 1100 RPM exhaust brake dropout speed can be programmed down to 800 RPM.
I think it was an AlfaOBD thing. Use the search function for more info on that. :thumbsup:

And Riverside Jeep, one last thing here...

I'd be real, REAL interested in hearing what the dealer had to say about this issue.
Honestly, I can hardly wait. :w:

Please keep us posted.
Thanks,
-Ej-
 
#13 ·
My deleted 2015, trans tune, will break in 1st gear, and my TQ converter only locks in 5th and 6th, very rare will it lock in 4th, and never on other gears. The E brake works in all gears, for me, locked or not. I only manual shift down to 2nd, as if I do 1st, it gets aggressive. If no one tailgating me, I can slow down to 2nd and turn a corner without using the breaks. I also tow about 8,000lbs travel trailer and never use tow haul. It will pull a hill with no problem and wont downshift.
I cant remember what it was like when it was stock.
 
#14 ·
My deleted 2015, trans tune, will break in 1st gear, and my TQ converter only locks in 5th and 6th, very rare will it lock in 4th, and never on other gears. The E brake works in all gears, for me, locked or not. I only manual shift down to 2nd, as if I do 1st, it gets aggressive.
I cant remember what it was like when it was stock.
Time to learn more about what you drive and how it works. You have yourself fooled pretty good here. Don’t take this personal, obviously you just don’t understand.
 
#26 ·
Yes, true, but on these trucks its where lockup is, (second gear, 1700-1800RPM) that is in question.

The OP is finding ways to descend that hill and keep it locked, to utilize his EB.

And again, sometimes you just have to press that stop pedal, as inconvenient and horrible as that sounds.
 
#28 ·
With a steep grade, and you want to hold around 10MPH, I would
1) Select T/H mode
2) Push the exhaust brake button ONCE so the yellow dash light is on. "Full Exhaust Brake Active" will be displayed.
3) Select 2nd gear on the transmission lock out.

After that I would modulate the brake pedal to keep the exhaust brake active and keep the speed where I wanted. When in tow haul mode, and light pressure is applied AND KEPT on the brake pedal, the exhaust brake will activate and stay active till below a certain speed. EVEN in first. It will downshift all the way to first to get the RPM's to keep the exhaust brake active, then release right about when your near a stop. You might be asking it to activate below that speed which if I remember from the last time I towed last week was in the low teens.

Scroll to the Exhaust Brake horsepower display and monitor how much is applied in your case.

Also there is no way I know of to electronically disconnect the front axle on a 19 model.
 
#30 ·
With a steep grade, and you want to hold around 10MPH, I would

1) Select T/H mode

2) Push the exhaust brake button ONCE so the yellow dash light is on. "Full Exhaust Brake Active" will be displayed.

3) Select 2nd gear on the transmission lock out.



After that I would modulate the brake pedal to keep the exhaust brake active and keep the speed where I wanted. When in tow haul mode, and light pressure is applied AND KEPT on the brake pedal, the exhaust brake will activate and stay active till below a certain speed. EVEN in first. It will downshift all the way to first to get the RPM's to keep the exhaust brake active, then release right about when your near a stop. You might be asking it to activate below that speed which if I remember from the last time I towed last week was in the low teens.



Scroll to the Exhaust Brake horsepower display and monitor how much is applied in your case.



Also there is no way I know of to electronically disconnect the front axle on a 19 model.


I have experimented with this type of procedure many times and a 68rfe, in stock configuration in a 2013, will not activate the EB in 1st gear. Only way I have been able to get EB to activate in 2nd is to first get it to activate in 3rd, then manually downshift to 2nd, regardless of EB mode or if TH is activated. Best bet for EB operation at low speeds is 4lo/2lo.


Sent from my iPad using Tapatalk
 
#33 ·
I right and not imagining
How do record on my phone and post reality to this thread/non beliavers
I have a fully deleted with trany tune on my 2015. I have the edge cts2 for guages only, and can record and audio my truck for the non believers.
The edge monitor only shows the locked up padlock in 5 and 6 and not often in 4th. And never in 1,2,and 3.
BUT MY EB works in ALL 6 gears manually down shifting.
I will video and audio it on my phone, but dont know how to post it, unless it's the same as doing a drag and drop pic thing
 
#36 ·
The exhaust brake needs a physical connection between the engine and the transmission in order for it to work via the TC being locked so that the input shaft is connected to the output shaft and not by fluid coupling. I would be curious to see a video of what you are describing.
 
#39 ·
After some thought, I thought of another way. Since the OP is asking for such a low speed, activate the downhill speed regulation, and set the speed to the desired rate of decent. I would also verify the trailer brake is in good working order and the gain is set.

In any event, the 2019's are DIFFERENT in many ways, so saying what works on a 18 and older won't help.
I just towed over 700 miles through the Smoky mountains and learned many new for 19 things. The trailer brake settings are totally different from my 13, and my exhaust brake will turn back on after I restart the vehicle. And yes, in tow haul mode with the Automatic Exhaust Brake setting activated, if I hold light brake pressure, the RAM downshifts all the way to first and the exhaust brake triggers with every downshift till about 12MPH? Didn't really take note of the exact MPH. The truck would even aggressively downshift at times to near redline. My 2013 would release the Ex brake activation much sooner.
Will post a thread on my towing observations soon. Big differences. 13-19.
 
#42 ·
I can utilize my EB down to 1040rpm in 2nd gear which equates to 14mph in my '14 equipped with 3.42's. Your '19 has 3.73's so should be able to utilize EB to ~12mph in 2nd gear. I believe you can't have 1st gear lock-up so that means NO EB in 1st gear. If you have a way of videoing it staying locked in first gear and utilizing the EB (via and edge cts2 or scan tool that can show status of the TC) then by all means, I'll believe you. As far as I'm aware the only transmission in a pickup truck that can lock in 1st gear is the new Allison 10L1000. Maybe the new 10r140 can as well but there is not much info on it at this time. The aisin, 68rfe, allison 1000, 6r140, etc, can't lock the TC in first gear; so unless you have a manual transmission you can't have exhaust brake in 1st gear.
 
#43 ·
Its just strange that I can go from second, ( now seeing it locked ) to 1st, no lock, and it still breaks. ( Might it be just the tranny, and not the EB,) as the tranny just coasts when downshifting without the EB on.
I only tow 8,000lbs for now, I might at some point get a 5ver. Its great to be able to use the EB to slow down and not use any breaks. When I have dumb people behind me, I touch the brake to light up the brake lights, so im not rear ended, wile using the EB.
Im very happy with the tune/s the person did to mine. It does/did, take a bit of getting used to, to have to go 50mph to get it to shift to 5th, then I can slow down to 40 or 45 and it will stay locked in 5th. And have to go 63mph to get it to shift into 6th, then I can slow down to 55mph in a 55 zone. I don't notice much from tow haul to no tow haul.
Thanks for all inputs, as it makes me understand better, but, still don't understand, it slowing down in 1st. ( now someone is going to steel my tranny and put it in the dodge museum.. )) I hope they get it out before the EPA, confiscates my truck and crushes it.
 
#44 ·
OP, if it's really a situation where you are taxing the service brakes to maintain speed (can't see how that's the case and rather you're looking to utilize the convenience of the EB) then a front axle 2 low switch will get all your EB back at low speeds, but you'll have to stop, shift into 4lo and then get our of 4lo at the bottom.
 
#46 ·
My stock trans tuning on my 68 will lock the TC in 3-6 (2-6 in T/H), no matter how aggressive of acceleration. So far the only thing I would change is that when I slow down and need to re-accelerate, it will just unlock the TC (staying in current gear, often 4th or 5th) accelerate gently and then re-lock the TC and upshift normally. What I would prefer is to downshift to lower gear, lock TC, and accelerate like I f-ing want it to. But I guess that is stock tuning for you, gotta make it comfortable and easy going.

Oh and there's the other thing of trying to go into 6th gear at 50 mph, but I easily fix that by just locking out 6th until I see the interstate.
 
#47 ·
I came from a Superduty to the Ram. I am not impressed with the pulling power of the Cummins! and I even more disappointed with the engine Braking. I tow a 14000lb fifth wheel, and everytime i get on a steep grade the damn e bake wont come on when i need it most! even with manually shifting the tranny down. works like a charm on the flat ground. I like the Ram a lot!! but I'm actually looking into how much money i will loose switching back to Ford. If i could only have test pulled my camper for my test drive. love the RAM until i put the camper behind it.
 
#58 ·
Something is wrong with your truck. I'd take it in to the dealer. My 2014 ram 3500 with 3.42's has a way stronger exhaust brake than the 2015 f350 with 3.55's. It also is a lot faster and stronger pulling trailers. The ford was a bit quicker off the line empty but way less passing power. You might have a dud vgt.
 
#48 ·
Ranprk, would that be a used or new Ram? A 2500 or a 3500? If 3500 DRW, what gearing?

My 3500 didn't run worth a damn when new, but has improved at lot over the past 6,000 miles. And the exhaust brake has always worked great.

You may have a 2500 with 3.42 gears, which would explain your disappointment with the pulling power, but not why the exhaust brake only works on level ground.
 
#49 ·
That would be a New 3500 Ram SRW, I don't remember the exact gearing but its comparable to the 3:55 in the SD. I have about 3000 miles and i am feeling a bit more ooph out of it. the braking just plan pisses me off. I live on top of decent hill, 2.5 miles to the valley. with the SD i never even needed to touch the brakes, this Ram, i need to tap them all the way down. coming up the hill with the SD, i could go as fast as i wanted, heck i actually would lift the peddle to slow down. The Ram, about 42 mph and its rr'd out and shifting back and forth with about 29 psi of boost. seams like it looses power the farther up the hill i get. Now i just put the 4 ways on and don't push it.
 
#50 ·
Okay, a new '18 or a new '19? If it's an '18 you're stuck with 3.42 gears, if not it's 3.73s.

Also, is that with the exhaust brake switched on or not?

Lastly, I think about 42 mph is the slowest mine has ever gone up a hill, and that's with 3.73s and smaller tires. Plus towing a decent load, of course.
You must live on one heck of a hill. What's the elevation difference, so I can figure out the grade?
 
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#51 ·
Sounds like something is wrong with your truck Ranprk. I have a 2500, so 3.42 gears and larger than factory tires. I've pulled 17k through back road hills of TN mountains (Cookeville area) and had no issue. Acceleration was more than adequate and EB was strong enough that I rarely needed my service brakes unless I needed to make a complete stop. Oh, and the damn trailer didn't have working brakes (not my trailer or machine, just moving it for a 'friend').


Sent from my iPad using Tapatalk
 
#53 ·
it's an 18, and about 650 ft of elevation, not all straight up. and yes i did stop today and looked at a SD, I'm not switching back anytime soon. I'm looking into the Stealth Module also. I like the ram, it actually sounds like a diesel compared to the SD. It pulls okay, just not as good as the SD. I've had the durmax and the power stroke. this is my first Cummins. I'm not really gender bias but i have always been partial to the RAMS. I had 98, an 01, and an 04. i switched to Chevy because the early rams rusted in three years, I really like the looks of the RAM, and that it handles the weight way better then the SD, its very comfortable. just doesn't pull as as well and stop as well with a load. I'm done whining, Ill make do, its still a solid truck. oh and it gets way better fuel milage. thanks for the conversation.
 
#54 ·
it's an 18, and about 650 ft of elevation, not all straight up.
Okay, so you have 3.42 gears. We're finally getting much closer to finding out what you actually have.

But if those 650 feet is the elevation difference, it's a measly 5% grade. That's not exactly what we refer to as "straight up" here in the Rockies.
Not even where I lived in CA, with an 8% grade for as many miles, and then it got steep for the last 1.25 miles.

Again, about that exhaust brake that supposedly isn't working; have you turned it on?
 
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