Exhaust brake with automatic transmission.......who's running one?

[Albino99]

I have a 1999 Ram 2500 4x4 and looking to pull the trigger on buying an exhaust brake. My truck is equipped with the 47RE auto. I have looked at many different brands and variations of these brakes. My final decision is to buy a Pacbrake PRXB c44075 kit. The concept of an exhaust brake makes sense to me and it only makes a difference if you can get the torque converter to lock-up. The c44075 kit does come with a transmission controller made by Pacbrake. I imagine it is an electronic brain that senses vehicle speed, rpm speed to regulate when the converter can be locked & unlocked. I emailed Pacbrake and one of their technicians assured me that this controller is all I need for safe and effective braking actuation. I am curious if anyone else here on TDR is running an exhaust brake on their automatic equipped 2nd gen? I would like to hear real-world stories of how folks like them and or problems/issues they have dealt with. (automatic equipped trucks)

 

[SnoKing]

In the fall of 2004 I put a Banks EB on our 2001.5, after having DTT custom build the transmission to be able to handle the increased line pressure needed to keep the TC locked via their smart controller. They also changed things to allow the TC to lock in second gear on the EB.

BD Diesel used an external device to increase line pressure. I am not sure how PacBrake handles line pressure, but Bill at DTT(the 47RE Guru) was was very clear on the need to increase line pressure while on the EB to keep the TQ clutch locked.

Study this older thread, that I was part of back then. Another poster in the thread talks about issues keeping the TC locked in a stock transmission(post #5). I wonder what PacBrake has to says about it.

https://www.turbodieselregister.com/threads/exhaust-brake-for-automatic.150566/

 

[petersonj]

I used to own a 99 with a 47RE and I did install a PacBrake exhaust brake. I wired in the "Mystery Switch", so I could tell the converter when to lock and unlock. Even doing that, I was still limited to converter lockup in only 3rd and 4th gear because it was a stock transmission. At the time automatic lockup controllers were not very effective because they would typically unlock the converter when engine rpm's fell below 1500 - the last thing you would need as you are approaching a curve on a downgrade. Additionally, some controllers would unlock the converter when the footbrake was activated - another great feature when approaching a curve on a downgrade. Not!

So, if you have a stock 47RE transmission with 3.54 gears and you were on an extended downgrade with a load, and the downgrade had some 20 - 30 mph curves, your exhaust brake will probably be useless even if the converter stays locked up. Plus, you will have to modify the 47RE transmission with a heavy duty lockup converter clutch and whatever modifications are necessary to increase lockup clutch pressure, especially at lower rpm's.

My solution was to sell the 99 when it had 70,000 miles on the odometer, remove the exhaust brake, and install it on my new 2002 with a six speed manual transmission. Problems solved - lockup in six gears! Awesome exhaust brake performance for 294,000 miles now! All on the original clutch and transmission.

If you are going to pursue this, I recommend that you have a thorough discussion with a knowledgeable transmission shop and the exhaust brake controller vendor. Ask questions like: Exactly what engine rpms will the converter lock and unlock. Will the transmission stay locked into gear while the exhaust brake is operating. Will the exhaust brake operation and converter lockup operation continue if the foot brake is activated?

Or...., you could sell your truck and find a nice used truck with a six speed (it will probably already have an exhaust installed).

- John

 

[SnoKing]

John above in correct in most of what he posted.

With the exception of low RPMs do not make much braking HP. The engine has to be spinning in the higher 2000's to have effective braking. That is why 2nd gear lock up is important.

All on this is why Dodge never offered EBs on the 2nd gen auto's.

My brake on the 2001.5 worked very well, but one had to drive it!! That is, it was not just plug and play, the driver had to know how to use it. It did lock to lock(TC clutch)shifts and a manual shift from 2nd to 3rd created a VERY HARSH shift with the smart controller on. So to make that shift I turned the smart controller off and back on with an old style floor mounted head light switch.

 

[Albino99]

I appreciate all the insight so far on this topic. I have been reading lots of threads throughout TDR, DTR, CumminsForum, and MoparMan about exhaust brakes and automatics. There is alot of info, but the results vary from person to person.

Some folks say to save yourself some coin and just make a "Mystery Switch" to manually lock up for exhaust braking downhill, while others claim they like an "automatic" setup that a controller provides. BD seems to have produced several varieties of controllers, (Autoloc, Torqloc, Towloc). I had to research all these models to figure out the differences and what they do. The Towloc seems to be the latest controller that allows a person to set parameters with a laptop computer. Besides BD Diesel's products, companies like (DTT, Suncoast, ATS, etc,etc) make their own controllers as well.

One thing is for sure, It seems I need an aftermarket Valve Body (VB) that allows higher line pressure for clutch engagement and also the ability to lock-up 2nd gear when I'm manually selecting 2nd to slow down. Each brand name claims that their product is more effective than the other when it comes to valve bodies.

I would honestly like to find a tried & true combination that works (Exhaust brake & Lock-up Controller). I rather not mix up brands and create a hybrid kit of parts, unless this is the only way to achieve quality and uninterrupted performance in braking.

BD Diesel's exhaust brake is vacuum actuated versus PacBrake which uses an onboard air compressor to supply control air. Which one is better? I am not partial to any brand, but just wanted to know which one people have had the most success with.

 

[DavidC]

Mine is a Jacobs and wires to the ECM and a on/off switch. Ties into the existing vacuum. No real sense investing in a vacuum pump when you already have one. I believe DTT no longer has the Smart Controller for TC control.

Dave

 

[DavidC]

Have you checked to see if the 99 has the famous 53 block ?.

Dave

 

[Albino99]

Have you checked to see if the 99 has the famous 53 block ?.

Dave

Yup, sure have. It is indeed a 53 block. My mileage is at 244,XXX. with no signs of any water jacket/freeze plug block stains in the culprit area. I'm not real worried about it honestly. If it decides to spring a leak tomorrow, I'll go find another engine to replace it with.

 

[DavidC]

Just wanted to make sure you knew the consequences.

Dave

 

[Albino99]

Looks like I might be going with the BD Diesel exhaust brake system with BD Autoloc controller. I talked with my local diesel shop and they had great things to say about it and answered all my questions. I also decided to call BD Diesel directly and talk technical with them on this system. They explained everything in detail and confirmed what my local authorized dealer (shop) had to say. Anyone on here running a BD setup?

 

[ARARAR]

I have run a PacBrake with a BD Autoloc on my 98.5 for over 150k miles and have never had an issue other than it hanging up on my trans dip stick tube and not releasing which I solved with a tie wrap to keep it out of the way.