Wyoboy

I have a 1999 dodge ram 2500 withe the 24V and automatic trany. I also have what I have determined as a engine break on the back side of my turbo. But from what I have read, in this era truck the engine brake is aftermarket and only works if the torque converter is in lockup and your foot is off the go pedal. I also have a switch witch allows me to manually lock and keep locked my torque converter. But I'm curious if this means I have to engage that switch each time I reach a crusing speed, or if the torque converter with lock up like it should. I'm also curious if, when I have the switch engaged, if I should hear anything coming from that engine brake when I let off the throttle? Any help is much appreciated.

KATOOM

You have whats called an "exhaust brake". An engine brake is totally different and something not applicable to the 5.9 Cummins.

How they work is by closing off a large butterfly venturi valve (controlled by either pressure or vacuum) in the exhaust brake housing, which shuts off most of the exhaust flow and creates massive amounts of back pressure inside the cylinders forcing them to work against each other and the resistance of exhaust flow. The amount of retarding pressure an EB offers is measured as a maximum 190 hp depending on the engine RPM. Meaning if it takes 190 hp to get up the hill in "X" gear at certain RPM then the exhaust brake will resist (slow the truck) with the same exact opposite force in that same gear going down the same hill grade at the same RPM. Again, the higher the RPM the more effective they are.

What you should look for is any identifying manufacture tag/label which would help you understand what you have as there are a few manufacture models which you could have, and they generally are not exactly the same in function or design. Some use a micro switch mounted under the throttle pedal and some connect to the ECM pin for an automated control. Maybe take a picture of what you have would help if you cant make things out.

As for the torque converter, yes they have to remain locked while the EB is engaged otherwise the EB will offer very little resistance and the transmission will build a lot of internal heat. How yours is set up is again, something I cant answer unless you knew what you have.

The noise you hear from your exhaust is probably a loud hiss and normal because you're hearing the exhaust work around that butterfly valve. EB's are very effective tools and need to be used very often in order to reduce carbon build up around the butterfly valve. EB instructions will tell you that they need to be used at least once per time the truck is driven. But on a positive note, if you use it all the time you'll become so accustomed to it slowing you that you'll find yourself hardly using the service brakes, which then reduces the wear and tear on those components. I have around 115k miles on my truck and there's still approximately 1/4" of pad material on factory original brakes. And I tow a heavy trailer too.