PacBrake Question

[LWalsh]

Any bad experiences with PacBrake PRXB?



I have the PRXB sitting on the bench new-in-the-box. When shopping for a mechanic to install it for me (I'm not equipped or inclined!), one guy told me I shouldn't install it on my '06 3500 auto, because I would have to repair or replace the transmission in 30k miles or so.



Does he know what he's talking about?

 

[rscurtis]

In a word, no. The '06 transmission is EB capable. Others more knowledgeable that I will probably jump in to tell you how it will interface with the ECM.

 

[HBarlow]

Yep, RSCurtis said it precisely as I would have. Your mechanic does not know what he is talking about.

I ordered one of the first '06 Rams, a 3500 DRW, with 48RE automatic and Jacobs Exhaust Brake from the factory but not installed. The brake was listed on the MSRP and Invoice and was in the box behind the driver's seat when it rolled off the transporter. Dodge could not interrupt an assembly line to have non-mechanic assemblers install the exhaust brake but it was sold for dealer install.

Several Cummins engineers, with cooperation from Dodge Ram, spent much of 2003, 2004, and 2005 in extensive testing and revision of the 48RE and the Cummins engine ECM to make the 48RE capable of handling the lock up and reverse thrust challenges created by an exhaust brake. The were completely successful.

All 48RE equipped '06 and '07 Rams are fully capable of use of any exhaust brake similar to the Jacobs or PacBrake. If properly installed the exhaust brake is fully integrated with the ECM, PCM, 48RE, and the Cummins engine.

The exhaust brake should be turned on and left on all the time except in low traction situations where it might cause a skid. When you lift your right foot the ECM will activate the EB and commence engine braking. As speed is reduced (if in Tow/Haul mode) the ECM will momentarily unlock the converter, blip the throttle to increase engine speed, execute a downshift from 4thOD to 3rdDirect, lock the converter, and reactivate the EB.

You'll love it and it will not damage your automatic transmission.

None of this applies to 2005 and earlier Rams.

 

[LWalsh]

Thanks, Harvey & RSCurtis.



I suspected that was the case, so I'll find a better informed mechanic!

 

[HBarlow]

Your signature does not reveal where you live but I have two friends who are both former Dodge dealer employees and good mechanics who would do it. One of them installed the brake on my '06 when I brought it home from the dealer.

 

[LWalsh]

Thanks, Harvey; but I'm a ways from South Texas. Spending most of my time in the FL Panhandle and East TN.



If anyone knows a good diesel mechanic near Panama City, FL, please let me know.

 

[cerberusiam]

Yep, RSCurtis said it precisely as I would have. Your mechanic does not know what he is talking about.

Careful there, you just went way out on a limb with no practical experience about what you are talking about.



You had a JACOBS brake, the OP has a PacBrake. Take a look at Pacs install documentation and it is clear it is NOT fully integrated into the ECU. That means no throttle blip, no unlock, no downshift automatically. All it seems to do is control TC lockup.



In that case, the mechanic is a whole lot closer to correct than you think. Comparing an integrated EB to a non-integrated EB is a bad idea, they work differently.



I would NOT put an EB on a stock unit without modding the trans, period. The only exception is the Jacobs due to its integration. If it can't control downshifting and TV pressure, its gonna be a problem.



I would check with Pac and see just how tight it is before assuming the mechanic is wrong.

 

[AH64ID]

One should be able to fully integrate the PXRB like the Jake, just have to use a Jake wiring diagram and some mechanical knowledge.

I couldn't imagine a non-integrated brake on anything.

 

[HBarlow]

Careful there, you just went way out on a limb with no practical experience about what you are talking about.

You had a JACOBS brake, the OP has a PacBrake. Take a look at Pacs install documentation and it is clear it is NOT fully integrated into the ECU. That means no throttle blip, no unlock, no downshift automatically. All it seems to do is control TC lockup.

In that case, the mechanic is a whole lot closer to correct than you think. Comparing an integrated EB to a non-integrated EB is a bad idea, they work differently.

I would NOT put an EB on a stock unit without modding the trans, period. The only exception is the Jacobs due to its integration. If it can't control downshifting and TV pressure, its gonna be a problem.

I would check with Pac and see just how tight it is before assuming the mechanic is wrong.

Sometimes you impress me with your knowledge. You are apparently a mechanic or automatic transmission rebuilder.

Other times you are full of crap.

Members have reported using a PacBrake instead of a Jacobs and claimed it was fully integrated just like my Jacobs was. I don't know if a member has specifically reported use of the PXRB or whatever it is.

 

[NIsaacs]

I couldn't imagine a non-integrated brake on anything.

Why not? All three of my trucks are just on/off, with a secondary switch on the throttle. Course they are all old and all standard transmissions



Nick

 

[cerberusiam]

One should be able to fully integrate the PXRB like the Jake, just have to use a Jake wiring diagram and some mechanical knowledge.

Its not mechanical, its electronic control and thats where its gets iffy. If the electronic control is not right it WILL smoke the transmission i short order. Thats why Dodge back pedaled on on EB on anything but an 06+. The ECU does not contain adequate controls to insure transmission reliability prior to 06.



The controller MUST be able to control lockup, OD, and TV pressure plus decide when to downshift to drive. That requires a rather sophisticated interface and the ability to read wheel speed.



Unless this is specific with the PRXB install, I can't find anything that says the integration is there.

I don't know if a member has specifically reported use of the PXRB or whatever it is.

Exactly. You don't KNOW if anybody has reported using it and how works. You don't KNOW if it integrates adequately. You don't KNOW how the PRXB works at all because all you had was a Jacobs.



I quote "All 48RE equipped '06 and '07 Rams are fully capable of use of any exhaust brake similar to the Jacobs or PacBrake" while not having a clue if this is true or not, by your own admission.



Now who is full of crap, eh Harv??? Stuck your foot in your mouth and then compounded it, AGAIN. :-laf:-laf



The OP never indicated what controller he has. Pac has 2, BD has a better one. Sooo, which one is the better one for the OP's truck? All I suggested was a little more research and NOT shooting the bearer of bad bews MAY be in order.

 

[HBarlow]

Once again, you have impressed only yourself and the back pedaling in your message indicates realization is dawning.

Speed sensor my ***!

The exhaust brake neither needs nor has whatever integration you are dreaming about.

The integration is all in the '06 or '07 Ram platform. It is contained in the ECM/PCM. If the exhaust brake, whatever name brand, is connected to the same wiring harness used by the Jacobs brake the ECM/PCM will turn it off and on exactly as it does the Jacobs brake.

 

[cerberusiam]

Once again, you have impressed only yourself and the back pedaling in your message indicates realization is dawning.



Speed sensor my ***!



The exhaust brake neither needs nor has whatever integration you are dreaming about.



The integration is all in the '06 or '07 Ram platform. It is contained in the ECM/PCM. If the exhaust brake, whatever name brand, is connected to the same wiring harness used by the Jacobs brake the ECM/PCM will turn it off and on exactly as it does the Jacobs brake.

Again more smoke and name calling cuz you got caught looking like a clown. I am calliing BS until you come up with something tangible.



Pray tell, Harvey, does your fully illuminsted totally integrated exhaust brake stay on all the way to ZERO mph? Hmmm? Wonder how it knows to shut off the EB when the speed drops below 30 or 35 mph? Hmmmm? Oh yeah, a speed sensor feed might work for that, ya think?



So there is the auto integrated mystical control interface that runs all the EB's, huh? Wanna dig that up in the FSM and point it out?



While your at it, you can tell us all about how the PRXB uses this interface and installs into the factory harness. Enquiring minds want to know.



Oh, thats right you have a JACOBS not a PRXB.

 

[HBarlow]

Your debate technique is known as creating a straw man argument.

I didn't call you any names and never suggested an exhaust brake has or ever had a speed sensor. That was the silly statement YOU made in an earlier boast and attempt to confuse the issue.

As I said and will repeat again - the 2006 and 2007 Dodge Ram platform integrates engine, exhaust brake, and 48RE automatic. The Dodge platform provides the on/off or activate/deactivate signal to whichever exhaust brake is installed.

You should stick to replacing brake shoes on Furds and rebuilding automatic transmissions on Chevy 1/2 tons. You probably know something about those two challenging procedures.

 

[BIGNASTY]

OK fight fans sorry for being late for the big one I dont know what round this is so take your pick. From what this fight fan (and ive been in a few!!!!!!!!!!) has seen the CLOWN took a DIRECT HIT to the crotch and is on one knee breathing deeply trying to swallow his canooooter IF SOMEONE COULD CLUE ME IN ON WHAT ROUND THIS IS I CAN CATCH UP!!!!!!!

 

[BIGNASTY]

The fight is SO FAST SO FURIOUS I cant keep up DANCE AROUND a little until I can. AHHHHHHHHHHH COME ON DID I MISS ROUND 3!!!!!

 

[RonD]

Once again, you have impressed only yourself and the back pedaling in your message indicates realization is dawning.



Speed sensor my ***!



The exhaust brake neither needs nor has whatever integration you are dreaming about.



The integration is all in the '06 or '07 Ram platform. It is contained in the ECM/PCM. If the exhaust brake, whatever name brand, is connected to the same wiring harness used by the Jacobs brake the ECM/PCM will turn it off and on exactly as it does the Jacobs brake.

I will try to explain it, I had one in my 2005 for 95,000 miles, and I installed it. It has the exhaust brake, YES, but it also has a little box, that is designed for specific applications, it is in other words a computer, it tells the trans what to do, so install the wrong unit, and yes the trans is toast in short order, this is not a 6 speed, it's a 48re that requires some thinking help.

 

[BIGNASTY]

IT'S OVER IT'S OVER IT'S OVER a knock out in WHAT EVER ROUND WHAT A FIGHT!!!!!!!!!! This one will go down in history of the TDR FIGHT NITE

 

[RonD]

Why not? All three of my trucks are just on/off, with a secondary switch on the throttle. Course they are all old and all standard transmissions



Nick

OK, and what do you think tells the torque converter when to lock, and unlock?

 

[BIGNASTY]

Ohh whats this its not over the crowd in texas is claming foul will this give new life to the clown???