48RE + Exhaust Brake: Current Status

[p-Bar]

Carlton,

You guys be sure to nurse that transmission so D. C. will sign off on the brake. Any update ??



Don

 

[thejeepdude]

Ditto what Don asked a month ago. . any updates? What about the pac-brake replacing jacobs as the DC recommended brake? Hopefully this doesn't set back the timeframe for approval.

 

[Carlton Bale]

Ditto what Don asked a month ago. . any updates?

The first of three vehicle tests is complete and we're about 15% into the second one. The dyno testing has also been completed. I haven't heard the tear-down results yet, but the transmissions were operating normally at the end of the tests. I am hopeful that everything will be approved. I'll let you know as I get more details.

 

[TravlinRam]

What about BD exhaust brakes

Thanks Carlton on the update. I too have been waiting for any news regarding the testing. I have a 2004. 5 ( build date Jan. 12, '04 ) 1 ton dually and pull a 140000 lb. 5th wheel. We traveled over 9000 miles this year mostly

out west. On my last truck a 99 Dodge 2500 I had a BD exhaust break installed a year after I bought it. What a difference it made going down long 6% grades. It would hold the truck and trailer at 55mph. I'm really considering

getting one installed on this truck before our next trip in April. At least with BD the torque converter is locked out while engaged. My question is does the BD exhaust brake have a different application than the Jacob's brake. Would there still be a thrush washer issue with the BD brake? Regarding any warranty issues I talked with the service manager at my dealer and he has no problem with it. I didn't have any issues on the last truck either. I still have a little over three months before we leave. Hopefully the results of the testing will be complete. Although I wonder if the early build date on my truck

will be a problem. Will the results of these test only apply to '05 models?

 

[Carlton Bale]

At least with BD the torque converter is locked out while engaged.

No, this is not the case. Using a box to send a lock-up signal doesn't make it lockup. The new software monitors transmission slip to make sure it really is locked-up. If it's commanded to be locked but doesn't actually achieve lock-up because of too much reverse torque, bad things will happen. This is explained in more detail earlier in this thread.

Would there still be a thrush washer issue with the BD brake?

Yes, it would.

Will the results of these test only apply to '05 models?

The software changes could apply to vehicles starting with '04, but the warranty approval may only be for late 04 and later vehicles. Again, it's up to DaimlerChrysler to make the final call on that one, but this is my understanding. MY04. 5 and later vehicles have a different ECM than MY04 and MY03. 5.



If you really want a brake on your truck, you can install one now, but it may not be approved by Dodge warranty if it causes a transmission issue. The new software really does add some great protection features and does everything it can to make sure the trans really does lock-up when commanded to do so but it may not be available many trucks.

 

[TravlinRam]

Thanks Carlton, I'll wait. Hopefully they'll get this issue resolved.

 

[yycguy]

No, this is not the case. Using a box to send a lock-up signal doesn't make it lockup.

My thanks as well Carlton on the updates, much appreciated.

I have a question regarding your statement about once a lockup signal is made that you are not necessarily getting lockup. Now I have the BD brake with their Tow-loc which is tied into the ECM. When I am in Tow/Haul and I am in loc-up it sure seems locked up to me? how would I tell if I wasn't or could i tell?

Thanks

 

[Carlton Bale]

Now I have the BD brake with their Tow-loc which is tied into the ECM. When I am in Tow/Haul and I am in loc-up it sure seems locked up to me? how would I tell if I wasn't or could i tell?

Well, that's the problem. You really can't tell if it is locked or just commanded to be locked. The new ECM software calculates transmission slip using various sensors and knows when the trans is in lockup when slip becomes zero. It also turns the exhaust brake off while the transmission is trying to achieve lockup during braking mode and won't turn the brake on until it is locked. If for some reason the trans can't achieve lockup, the ECM stops sending the lockup command after several seconds to prevent any transmission issues.



During the 48RE / exhaust brake testing that was initially conducted last year (with different software than we are using now), we had one instance where the lockup signal was sent for 3 minutes but the transmission did not lockup and the brake was on. This caused internal overheating, resulting in complete trans failure 2 days later. If the trans doesn't achieve lockup but keeps trying to, there is no lube / cooling flow within the trans and bad things happen. This is the issue that set testing back so far; it took quite a bit of software development to be able to detect and prevent this situation. Any "box" that blindly sends a lockup signal with no feedback for transmission slip can result in problems, especially if the trans is unlocked when the brake is activated. Trying to lock the trans with the brake on is what can cause the situation. That's one of the big differences between the production software and the new test software.

 

[KYLE4]

Carlton is right guys and gals I can't take the credit for what I learned my friend Dave Meheen told me about this how the thrust bearings in the transmission's would fail during exhaust brake use. I did take the liberty and call one of my supplier's BD Power and their Exhaust brake department told me they were having no such problem with their line up of exhaust brakes so there is my input

I just received official word from DaimlerChrysler engineering that an issue was identified on the 48RE transmissions that were tested with exhaust brakes. These were test vehicles that took a couple of trips out west (over the Rockies) and back. Apparently, the reverse loading from the exhaust brake caused unusually high thrust washer wear in at least one location.



At this point, I'm not sure exactly how this will effect plans to give warranty approval for the 48RE and the exhaust brake. I'm not sure if revised thrust washers or other changes will be designed and if they will be reto-fittable into existing transmissions.



I'll let you know as I find out more. At this point, I don't have a great deal of confidence that warranty approval of the 48RE and exhaust brake will happen by the end of this year.

 

[FDrake]

I guess I don't understand why someone would not know if the transmission was locked up. When I had my 1997 diesel with the auto transmission, it was not advised to have an EB. The warnings about slippage and overheating were numerous. I had no problems but maybe here is why. When I reached the crest of a hill I first set the cruise control at a speed about 5MPH UNDER the posted spped limit. Then I engaged the EB and the cruise control held the speed to where I set it and the transmission was locked up. It never caused me a problem and held the speed where it was set. Can't that be done to the new trannies with the "Tow/Haul" feature? Did DC go backward when they redid the new transmission? The new transmission on my 2004 diesel holds downgrades well but I would feel better if I had the EB option.

Frank

 

[Carlton Bale]

Frank,



The procedure you used may work to make sure the trans is in lockup. However, making sure every singe driver did that every single time is pretty much impossible and Dodge would never warranty-approve such a complicated scenario. The 48RE is definitely not a step backwards; we're getting close to warranty approval if everything continues to go well.

 

[yycguy]

Carlton,

I have a 04 Ram with the 48Re , and the BD engine brake with there Tow-loc. My procedure is to engage the tow-loc with the engine above idle ie. under power once I have achieved lockup I then let the throttle to a idle and the brake and tow-loc are engaged. Of course I do this prior to starting down the hill that I want engine braking. Now this procedure is a bit of a pain as you have to ensure you have a hi enough throttle and speed to get loc-up. So I fully understand your comment about the general public let loose with this setup.

 

[p-Bar]

Carlton,

How about an update every two weeks to keep us updated. Alot of us are fired upped but don't want to bug you.



Don

 

[Carlton Bale]

Good news so far. The transmission and the converter were both "normal" from the dyno testing. The transmission and converter were both "normal" for the first of the three tow tests. The second test is about 70% complete and I'm expecting the same results based on the data I've seen.

 

[brillmtb]

I was told by local dealer/mechanic that all you need to do on the 03 48RE is to keep the line pressure up with a BD type device and then the OD will stay on to lower speeds and you can then use a exhaust break.



I mentioned the ? bearing issue but he stated he has not seen any failure there but understands that they went to a needle bearing to better take the reverse torque.



He didnt feel the 48RE would suffer from an exhaust break if you did the above.

 

[p-Bar]

Go ahead and do it D. C. won't warranty it . You will be on your own. Their is no gaurantee that the torque converter will stay locked up.

 

[LightmanE300]

When an aftermarket transmission upgrades like ATS/DTT is installed, is this problematic thrust washer replaced? Would it be replaced with just a tq/vb upgrade or would a full trans replacement be required to get to the thrust washer? I'm just trying to figure out what I need to do to safely run an EB on my 48RE.

 

[p-Bar]

When an aftermarket transmission upgrades like ATS/DTT is installed, is this problematic thrust washer replaced? Would it be replaced with just a tq/vb upgrade or would a full trans replacement be required to get to the thrust washer? I'm just trying to figure out what I need to do to safely run an EB on my 48RE.

Lightman do you have a 04. 5 0r an 04



Don

 

[jcarey]

Lightman300, A TC and valve body would not involve the replacement of the thrust washer. I'm pretty sure Bill Kondalay has an upgraded washer (he's the one that brought it to everyone's attention about a year ago. I haven't heard about one from ATS.



Jim

 

[WoodChuck]

When an aftermarket transmission upgrades like ATS/DTT is installed, is this problematic thrust washer replaced? Would it be replaced with just a tq/vb upgrade or would a full trans replacement be required to get to the thrust washer? I'm just trying to figure out what I need to do to safely run an EB on my 48RE.

Changing the thrust washer would require disassembly of the transmission. If you were doing a TC upgrade anyways it would be and ideal time to replace the suspect washer. Half the work is just R+R ing the trans (and transfer case if 4x4).