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48RE + Exhaust Brake: Current Status

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Finally ready to install exhaust brake . Advice welcomed

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dandlwiley - re-read my last post.



I suspect that the key issue isn't the strength of the 48RE but the controlling software and the sensors needed to feed data to the software.



My speculation is that the combination simply isn't working in the manner that they want it to: it isn't a seamlessly automatic interface.



If their goal is to have the computer handle everything, that would, indeed, mean major changes in the software and might require some kind of sensor to determine how much retarding force is being applied to the transmission [for the protection of the transmission as well as to let the computer determine when to downshift so as to maximize the effectiveness of the E-brake].



As it is, I wind up driving mine more like a manual - downshifting @ ~1800-2000 RPM - than like many would drive an automatic.
 
If the dealer installs an exhaust brake on an automatic and claims it won't void the warranty, get it in writing, because I'm pretty sure that DC would void your warranty, especially for transmission failures.



As for the use of an exhaust brake on an automatic, if you don't lock the TCC, the brake will be ineffective unless you're not towing or otherwise carrying a significant load. There is no software or device that I know of from DC that provides TCC lockup for the exhaust brake, so if the dealer installs it, what are they using for a lockup controller?



If you have a stock trans and torque converter, you will likely damage it if you use an exhaust brake and a lockup controller.



Also, downshifting to 2nd with the exhaust brake on and the TCC locked can bend or collapse the stock front band strut.
 
Originally posted by emjay

There is no software or device that I know of from DC that provides TCC lockup for the exhaust brake



That software must be the same as Carlton was referring to re: the hardware and software for the MY04 and MY04. 5 models.



Dean
 
Emjay, you might wish to review the changes incorporated into the 48RE.



Lockup is provided in 3rd and OD. [When you "tromp" on it, from a standing start, there are 5 obvious shift points. ]



The 48RE was specifically enhanced to work with the Jacobs.



As I've said, I'm speculating that the primary reason that D/C didn't complete their "testing" in time for general approval on the 2003. 5's is that the combination isn't working in a "seamless" fashion.



All I, personally, can attest to is what I've posted before.



If mine breaks, I'll be sure to let everyone here know what the outcome was.



Of course, if it doesn't break, there won't be any issue. :D
 
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I just made a print out of this whole thread and took it down to the Dodge dealer. Our sales rep, the Fleet Manager was working today. He says they will stand by this application throughout the regular warranty period. I have a copy of a DC publication that comes to the service departments--and he gave me a second copy today--that states the 48RE is compatible with exhaust brakes. He checked with their service department before having the Jake installed and they said it was OK. Will definitely get this in writing Monday. . If there are some aftermarket transmission guys on this forum I'd like to hear your thoughts on this subject. I'm glad we have a Cummins rep willing to take the time to give us the correct information--thanks, Carlton. Getting info through DC is like pulling teeth.



Linda
 
New hardware on 2004 48RE?

Well, Here it is August 2nd.

Shouldn't the first 04's be coming off the line by now?



It would be very good to know if the new hardware for the jake brake is onboard the new 04 autos. Anyone know yet?



Ordered my new beast a week ago, and the long wait begins. Oo.
 
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TCC lockup has always been in 3rd and 4th. That's not new. The question is whether the TCC remains locked at closed throttle, which is necessary for decent exhaust brake performance. Also, a lot of the 47RE transmissions prevent a 4-3 downshift when the TCC is locked. If they changed the VB to allow it, there's also the jolt you get from a 4-3 downshift with the TCC locked and the exhaust brake on.
 
Oh yes, and the term used in "the bidness" for software features that are promised but not implemeted yet is "vaporware". :D

Only time will tell... .
 
Originally posted by dandlwiley

I have a copy of a DC publication that comes to the service departments--and he gave me a second copy today--that states the 48RE is compatible with exhaust brakes.



I don't suppose you'd like to share a copy of that with me so's I can take it to my dealer, would ya? :D
 
Kilby, right now what I have and a dollar would get you a cup of coffee. I have a copy of pages 7, 8, and 9 of an unnamed in-house (Dodge) publication that the service department receives. The only identifying information is "2003 Powertrain Update. " My husband is gone for the weekend at the family farm doing fence work--when he comes home tonight the **it will hit the fan 'cause he doesn't know about this! Tomorrow (Monday) I'm certain he will be firmly seated across from the Fleet Manager and will try and figure out what we are going to do. At that time we will try and get the information--name of publication, etc--for this copy. It is information on the 48RE and how it is different from the 47RE. The last paragraph states: "Unlike previous automatic transmissions, the 48RE allows the use of an exhaust brake, too. All in all, it is a very robust transmission. " We will also try and get some information from the better after-market transmission fixers that contribute to TDR. I would like to find out exactly what the problems we might have if we leave the Jake on.



Once we get the original source of this copy located and copied, I will share it on this forum. Should be able to scan it and have it available to send.



CARLTON: If you read this: What would you do if YOU had a 2003 with under 200 miles on it--and a dealer-installed Jake Brake? We can take it off, leave it on, or Dodge will buy-back the truck. We haven't towed anything but a 17' trailer with an automatic before so don't know if we can get along without an exhause brake. We wouldn't tow without an e brake with a stick.

The dealer will put in writing THEY (not DC) will guarantee the transmission up to the 7/7000 warranty. This dealer is as honest as they come--they can be trusted.



Linda
 
Originally posted by dandlwiley

The dealer will put in writing THEY (not DC) will guarantee the transmission up to the 7/7000 warranty. This dealer is as honest as they come--they can be trusted.



Linda,



It sounds like your dealer is very reputable. They are offering warranty coverage and will give you that in writting. Go enjoy your new truck!
 
Carlton: Talked to dealer today--unfortunately the owner, who has the last say, is out of town till Thursday. Husband doesn't was to risk it, even with the dealer guaranteeing it. If something happened far from home--then what. They have a 6 speed in Graphite with a Silver bottom--the only other color than white we would accept since it matches our trailer perfectly. We are looking at an exchange since it is very close to having the exact same equipment. Luckily we hadn't installed any of the extras on the 48RE truck except the Prodigy brake control and had only put 256 miles on it. That 6 speed is one smooth shifting truck--think our old knees and hips can handle it!



Kilby: Couldn't get ahold of the info from the service department, but will do so this week--if they will cough it up.



Linda
 
Originally posted by dandlwiley

It is information on the 48RE and how it is different from the 47RE. The last paragraph states: "Unlike previous automatic transmissions, the 48RE allows the use of an exhaust brake, too. All in all, it is a very robust transmission. "



Linda



This reads like an informational bulletin that has been out a long time, and was posted on the TDR almost a year ago. That had us all expecting the 48re for 2003 would be e-brake certified when it was available starting about February, 2003 (December 2002 orders). Unfortunately, they were not done with testing yet when the info bulletin was issued, and the final word seems to be, "wait for January 2004".
 
Originally posted by dandlwiley

We haven't towed anything but a 17' trailer with an automatic before so don't know if we can get along without an exhause brake. We wouldn't tow without an e brake with a stick.

Linda



Having had a Jacobs brake since my 98. 5, I feel the same way. The Jacobs Brake for the '03 seemed like a long time coming. There were production problems with the developement and manufacture of the vacuum pumps that, at least in part, led to a substantial price increase that many were unwilling to live with. I had my brake on back order from November until March.

I am very happy with it, most others seem to be, as well. I think that the dandlwileys will be very happy with the smooth 6-speed and a waranteed Jacobs brake.



Dean
 
Wednesday our white truck goes back to dealer and is exchanged fora Graphite/Silver 6one with a 6 speed. The Jake will be moved to the new truck as well as our brake control. Trucks have nearly the same options--except no power pedals which I REALLY would liked to have since I'm short. Truck will look good with our 2002 Arctic Fox with gray and silver decals.



The new TDR came today and offers the first explanation of why not to use the Jake with the 48RE:



"Final notes in the on-again, off-again world of official factory approvals, the installation of an exhaust brake for use with the new 48RE transmission is not yet approved (6/27/03). The engineering community is working to make sure that there is not the possibility of the exhaust brake being operational in a scenario where the torque converter is not locked up. Without torque lock up the fluid in the torque converter is "sheared" as the driveline works against the engine. Sheared fluid gets hot in short order which can lead to transmission problems. Not to mention, without the torque converter locked up there is not full braking effect--again, all you are doing is shearing (heating) the transmission fluid. We will post updates as we have them. "



From the Third Generation section, page 52, Issue 41, edited by Bill Stockard and Robert Patton. Note: This paragraph was at the end of an article on how to install a Pac Brake on a 48RE!
 
Seems like it would just be a matter of changing the TC and perhaps new software program?



Anyway, with my 22 foot Artic Fox, 40 gallons of water, packed full of camping gear I fortuantly have not found the need for an exhaust brake. Perhaps with much bigger trailers. I am able to Coast, take off OD or on really steep windy grades go to 2nd and have to use little brake, certainly nothing that is going to cause a dangerous situation. There is more "braking force" in this trucks motor than I expected for a diesel.
 
Carlton, you talked about hardware changes maybe being in the MY2004 and I just got my latest DRBIII update CD and it talked about a new ECM CM848 for the 2004 Cummins. It also talked about several sensors and input/output that this controller would have when paired up with an auto trans only. Is this ECM and the sensors and input/output most of the hardware changes that you had talked about hopefully being in the MY2004??? Once again thank you for all the helpful information you have provided to the forum.
 
One last update to hopefully end the saga of the 48RE and the Jake Brake! After deciding we would be VERY happy with the Graphite truck with 6 shooter we hit another brick wall. The truck was already sold! A salesman didn't follow the usual procedure to mark it sold and move it into the back lot. Not a 6 shooter in the zone that matched our specs. Dealer said they would buy the truck back. Went in, filled out and signed all the papers. Dealer taking a beating on this because we bought below invoice and the truck was titled so was considered used. He made a counter offer--we went home and considered it, and took them up on it. WRITTEN, signed warranty by Withnell Dodge, Salem, OR, for 70K miles. Tow reimbursement if the transmission goes (not really necessary as we have tow insurance). They refunded the cost of the Jake and installation and leave the Jake on. If a retroactive fix is developed they will install it and at that time we will pay them back the amount they refunded. The main problem seems to be making certain the TC is locked before operating the Jake. Got our trailer hitch switched today--had to go back to the class IV from the TItan V we were using. Installing the Class V receiver (it goes below the factory receiver0 would drop the hitch too low for our high riding trailer. We found our tongue weight was lower than we thought so the 1200# bars and rating will be OK. Now comes the canopy, running boards, gauges... . and on and on. Thanks for all the advice and support. TDR members are the best!
 
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I think, all things considered, you made a wise choice, and you can't complain about the terms. You have one heck of a great dealer. I have very positive relations with my dealer as well. I guess we are just lucky:) . According to Carlton the hardware will be different on the 04's, but if your dealer will upgrade for the $1285, it might be a consideration. Good luck with your new truck.



Dean
 
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