I was wondering if anybody had ever heard of putting a compresion brake (Jake brake) in a 6.9/7.3 before. Or any small diesel pickup (small compared to the Kenworth I am used to) for that matter.

 

For whatever reason, you can't use them on smaller diesels. That's why everyone uses exhaust brakes.

 

There is an exaust brake available but no jake type that I am aware of.

 

No jake for smaller v8s but I think you can get them for a 5.9 cummins. An exaust brake will make a world of difrence if you have a stick or a properly built E4OD

 

Jacob's engine brakes alter valve timing to get engine braking, and they are not available for either the 6.9, 7.3 or 5.9 engines.

But exhaust brakes are, the close off the exhaust pipe to create back pressure.

 

I know exhaust brakes cause allot strain on the drive line, Is it worth adding one or will it eventually brake something.

 

I have seen a lot of Cummins powered Dodges with exhaust brakes that have caused absolutely no damage. If you use the one Cummins offers it doesn't even effect your warranty. Actually none of them would effect the warranty unless the manufacturer/warrantying agent can prove it caused the problem.
Obviously no one on here is worried about their warranty but the engine manufacturers don't seem worried about their use.
The new 6.7L Cummins has an exhaust brake from the factory that is really just part of the turbo.

Basically I don't think you have to worry about engine damage as long as you use a brake made/desighned for the IDIs. I think BD makes one.

I have heard the IDI exhaust brakes are not as effective because of the lesser power of the valve springs. I know in respect to the Cummins 12V motors there are brakes made for the factory 30-35 lb. springs and a more effective brake for those who wish to swap in 60 Lb. springs.

 

No more strain than the power of the motor.

Where the problem comes in (the same with a Jake Brake) is going from power to braking creating a backlash on the drive train.

It's all in the use, Iron Horse Cowboys that miss use Jakes can really tear up a drive train.
Power / Jake / Power / Jake / Power / Jake beats the heck out of a drive train.

Shifting with a Jake is also very destructive! I've seen rods bent doing this.

Exhaust and Jakes brakes are not meant to be used around town! They are meant to hold back the vehicle while going down a grade.

-Enjoy
fh : )_~

 

I know guys who use their exhaust brakes virtually all of the time as they don't make noise like a Jake brake does.
On the Cummins anyway, they don't seem to really shock the drivetrain at all, especially with an auto trans. Also especially if you roll out of the trottle instead of just jumping off of it.
Some of these guys have been doing it for 10-15 years and the only thing they have noticed is their wheel brakes last forever.
You have to drive differently as letting off of the gas gives a whole different dynamic with the exhaust brake on. You don't "roll" to a stop, you "brake" to a stop in A LOT shorter distance.

 

I'm fairly certian the 6B cummins aka the 5.9 has had a jake on it before, thats what gave me the idea. I would be real suprised if any sort of engine brake could damage the drive terrain. I guess if you had a guy that really sucked at driving a manual tranny could get some bad back lash going. I would also be really suprised about shifting down with a jake bending rods? In 20 years of being around the big trucks I have never heard of such a thing. Not trying to argue with whoever wrote that, I just never heard of such a thing. I guess an exaust brake is the best I can get altho I love the sound of a big CAT 3406 jakin down exaust is all I get. Anybody have any good outlets for a 6.9 exaust brake or would I have to build it?

 

Nope, 5.9L Cummins has never had a Jake. Only exhaust brakes.

 

i could see down shifting with the jacks on causing some serious damage if you dont do it right I've been pulling trucks up to the shop that the driver left the jakes on and when i got to float it between gears it gat get kinda violent, now I make sure there off untill i come up on some one walking then flip em on speed up and let off and scare the pants off em.

 

My exhaust brake on my Cummins gets turned on when I start it in the morning and stays on all day. In town, in the woods, and on the highway.
In town, I barely use my brakes. I also use an engine brake in town on any truck I drive. Although I never shift on the jake.

You can do some damage if you are constantly on/off/on/off on the throttle. But it probably isn't going to make a difference whether the jake is on or off. That's just poor driving, IMO. When the exhaust brake comes on in my pickup, it is pretty smooth. But, if I drop to a lower gear and let off the throttle, the brake comes on and then the torque converter locks up for more braking power. When the converter locks, it is very harsh. But that is how the factory engine/trans programming is.

I don't think that using the jake to shift can cause much, if any damage. Even some of the auto shift automated manuals will engage the engine brake between shifts, if the conditions are right.

I have heard that the problem with using an exhaust brake on an IDI has to do with the valvetrain and the hydraulic followers that are used. That they have a tendency to flutter the valves and can break springs or damage the valve seats.

Jason

 

I didn't think about the difference between the hydraulic lifters VS. the solid lifters in the Cummins. That makes sense.

 

We have been successfully designing exhaust brakes ever since the 6.9 and continue to right up to the 6.0L and soon 6.4L. There are no concerns with the engine or transmission damage if the brake is installed and setup correctly and installed with a transmission controller in the automatic applications.

Let me know if you have any questions on the BD Exhaust Brake or Click the below image for more details, member pricing is available!