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PRXB exhaust brake on a 2004.5 48RE

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No codes loss of power

tcole

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Superdawg

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Okay. I've read up on many threads reference this topic. This may seem like beating a dead horse so I will apologize up front.
I am very serious about putting a PRXB on my 2004.5 48RE with a build date of 4/04. Stock power. The PRXB for my truck is C44052.
The trans has been rebuilt 2 yrs ago, local stock build, thrust washer installed, no name slightly lower stall torque converter and valve body to match torque converter. Not likely valve body was upgraded for exhaust brake use.
The PRXB appears to use an ATS Co-Pilot to keep the line pressure up on the torque converter. The Co-Pilot has different settings (inside) to work with the different years of the Dodge. I assume the different models of the PRXB have to do with the different settings on the Co-Pilot.

I read that the concern is if you don't have a valve body set up for an exhaust brake, when the throttle is off and EB is on, line pressure can go to zero and the trans slips. Is that still a concern today with the ATS Co-Pilot?

On a relatively stock valve body with the ATS Co-Pilot, will I have EB capability in 3-2-1 or just 3-2?

Would the BD Torqlock do the same as the ATS Co-Pilot or does the BD do more?

A couple notable posts from the past:
from: cerberusiam:

Quote Originally Posted by Kry226 View Post
Early 04. 305/555/48RE
The 04 trucks have at least 2 different series of ECU's on them, it is hard to tell what is in each one. The break on the series came at about mid year so an 04. 5 might have additional programming that you would not have in an earlier model.

I would install a PAC barake and wire it for the 2006 application, put a pressure gauge on the apply pressure port and use it. If it does not hold lockup correctly and the pressures are too low then look at a PowerLoc and shift kit\TC upgrade.
2005 3500 SRW 4x4 QC LWB 3.73, 48R


Quote Originally Posted by DRyder View Post
BUT, there is a funny little switch on my gear selector call "TOW/HAUL" that if depressed it will shift out of OD, down to third and lock the TC until what feels like 18 mph
Cerb: Yes, the TH switch will take it out of OD which is needed. However, at 18 mph there is not enough engine rpm to provide braking and the apply pressures are too low to hold a load. Under a load it won't hold lockup down to that speed and if it does it will slip the clutches.

Thanks in advance,
Tom
 
I read that the concern is if you don't have a valve body set up for an exhaust brake, when the throttle is off and EB is on, line pressure can go to zero and the trans slips. Is that still a concern today with the ATS Co-Pilot?

On a relatively stock valve body with the ATS Co-Pilot, will I have EB capability in 3-2-1 or just 3-2?

Neither the line pressure nor the TV pressure (clutch apply pressure) goes to zero when you lift off the throttle. They go lower than you really want with an EB which is the problem. Stock VB off throttle the apply pressure is only 50-55 psi, with a shift kit it is better at 70-75 psi. You really want 120-130 psi apply pressure to use an EB and not have issues.

The only way to get the higher pressures to happen on a pre-05 truck is use what BD quit making called a PowerLoc IIRC. It was an electrical activated cylinder that bolted to the TV lever that when you lifted off the throttle and the EB was active it would max TV pressure. That held pressures high and forced downshifts so you could get down to 15-20 mph using the EB. Maxing the TV pressure causes the trans to automatically downshift as you slow.

All the offerings now by ATS or BD require the full electronic shift transmissions or a TTVA motor to cause an auto downshift, all they do is hold TC lock until the set speed. Even in drive 30-35 mph is that is useful as engine pressure has dropped to far, you will have to manually downshift to use them below that. Then, you better have higher pressures a billet input because you are doing locked to locked shifts.

Shift kit is mandatory, throttle closed pressures need to be minimum of 75 psi. Preferably more if the trans will still shift correctly with them that high. It will work but depending on load and usage it may not be that good for the trans.
 
Thanks Cerb. That gives me some things to think about. In a perfect world, I would like to upgrade the torque converter, valve body and a few other things to make the EB work well.
 
Your EB will work well because you have a 04.5 ISB600 and this ECM and Valvebody is capable to to work with an OEM Jacobs Brake, it holds the Linepressure at 110psi with switched on JB, it has forced downshifts 4>3 and it locks up the TC and holds him locked down to around 20mph.

So does my Truck with the JB I installed by myself.

I've written a lot about that in other Threads, there are some little things that must be watched over when using it. It is NOT idiot proof by definition and that's the reason why dodge doesn't recommend it on this truck.
 
Ozy,
Thanks for the info. Did you have the EB before the TransGo, BD Converter, and BD PressureLoc?
thanks,
Tom
 
Yes, it was the first part I installed after buying the truck, I need that brake where I life - in the Swiss alps.
 
And i need to change my signature, the pressureloc isn't needed on my truck, it doesn't help in any way. Truck makes the same by itself.
I had wrong information back then when I bought it.
I disassembled it some time ago.
 
So, putting it together, on my stock 2004.5 48RE, 20k on a rebuild, I will probably need the following:

Pacbrake PRXB C44052
ATS Co-pilot (included in kit)

Transgo shift kit # SK 48RE

This sounds like it might work but it could be hard on the trans. I am a little concerned about the lower speed 3-2 locked to locked hard shifts on a stock TC and VB. If I understand it correctly.

I realize an upgraded TC, billet cover, input shaft and VB would be ideal but at that rate, might as well go through the whole trans.

Anyone besides Ozymandias want to chime in on their experience with an EB on a stock 2004.5 48RE?

This is a great site and I am grateful for the advice and sharing of experience.

Tom
 
You will never regret the PRXB. My truck is the 6 speed stick (G56). I put it in about 8 years ago and the only thing I have had to do to it was I upgraded the compressor about 2 years ago and finally the solenoid valve developed a small air leak about 6 months ago. It was the best add-on I did to my truck. Period!
 
I have another question. Is the Transgo shift kit sort of a first step toward a built valve body such as one from BD or Goerend?

I am also going to replace that little coolant hose/clamps behind the turbo while I have the elbow out for the EB.
 
I have Goerend parts in my trans. valvebody, tripledisk TC and billet input shaft. I have BD exhaust brake. The VB doesnt have the exhaust brake upgrade in it they did send parts to me but seems to work fine. I am using BD's torqloc
 
I have another question. Is the Transgo shift kit sort of a first step toward a built valve body such as one from BD or Goerend?

It is usually the only step to build a VB. There are a host of changes that can be done to VB to address specific needs but a typical built VB will have the same changes and likely the same components as various shift kits. The difference is the VB builder shave their system and bulk parts to do a lot of them.
 
I will send it to a trans shop to have them install the shift kit.

Another post by Cerb from 2012 reference 48RE upgrade:
I have used some of them, the manual valve and TV repair kit, but not the rest. Haven't really needed them.

Most of the pieces in that kit are for worn or out of spec pieces in the VB. You have some pretty specific problems that they are intended to cure, sloopy forward and reverse engagement, sloppy lockup, buzz in the transmission. Some of them do not apply to the 48RE as those have been addressed and fixed.

If all you are having problems with is the slight shifting issues you noted its doubtful the kit will address it. Won't hurt but probably won't help.

Park not lighting all the time is probably a shift cable adjustment. The adjuster is under the steering column behind the knee bolster. Its just a clip that hols the houisng in a bracket. Easy to adjust and get alignment again.

I think there is a significant difference in the OE style upgraded solenoid and the GM style, especially if you are doing a shift kit. The OE style part has not proven to be that much better for the cost. The GM style just about never fails. Any problem I have heard of with it have been traced to install issues or other trans problems.

Basically, if you do a shift kit you should do billet front servo, billet accumulator, billet band strut and anchor. Sealing rings on the direct drum support and the billet rear servo are other things that need addressed at some point but not as critical as the others. They require trans disassembly also where the previous pieces only require dropping the pan and the VB.

If you like and are familiar with the TransGo kits then by all means use it. Mine works great but if I had it to do again I would use the Superior shift kit. Easier and less intrusive to install and from all accounts as good of results as the TransGo.

To improve lube and cooling internally will require trans disassembly. About the best thing you can do without tear down is a shift kit, manual valve, and get rid of the check ball in the cooler line.



So, if the trans shop is going to install the shift kit, should I have them put in a billet front servo, billet accumulator, billet band strut, slip in front band (carbon lining?) and anchor too?
 
Definitely intermediate (front) servo, billet band strut and anchor. The TCS servo is the one you want to use, close to same size as stock, better sealing, and it doesn't require a lever change.

You cannot get a slip in band with the carbon fiber mix lining, all I have seen is the red lining. The Raybestos semi rigid with carbon fiber is about the beefiest and best material I have seen so far but it does require disassembly of the front part of the transmission. The slip in band is better riveted and has more surface area than the stock style band so it has some worth. The stock style band will eventually have issues with too much pressure in the apply circuit, and, they want to stretch over time. Will depend on how the VB is setup for pressures, I run a lot of pressure in the system to hold the TQ but that can be adjusted with the PR valve springs.
 
Thank you.
I ordered the following to be installed with the Transgo shift kit:
TCS Performance Transmission Products A518, A618, 47RE, 48RE Combo Kit K1469CP
The kit contains:
The TCS billet aluminum dual ring servo and accumulator piston - for "ZERO" leakage 2nd gear apply, longer band and 3rd gear life.
The heavy duty quick ratio 4.2 band lever provides greater mechanical clamping force than the O.E.M. 3.8 ratio lever.
The unbendable heavy duty band strut is TCS's solution to the O.E.M. band strut that is notorious for bending causing excessive band clearance and transmission failure.
The billet steel band anchor - for heavy duty and performance applications, positive band adjustment. This heat treated and zinc plated anchor delivers reliable and accurate band adjustment.

Transmission Technologies Band, slip in kickdown TAT54994R

Anything else to tell the transmission guys while they install?
thank you,
Tom
 
Just none note, the 48 RE has a 5.0 band lever not a 3.8. That was a 47RE item. You would want to leave the 5.0 lever in unless they are going to tweak the VB to use the 4.2 correctly.
 
Truck is going to trans shop next week for:

Trans go shift kit
Billet front servo/accumulator
Heavy duty strut
Keep existing 5.0 lever
Billet band anchor
Slip in band

What is a manual valve and should I put one in?

Should I also have them install Sonnax Valve Body Detent Ball & Sleeve Kit
Part No. 22771-12K as preventative maintenance while they are in there?
 
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