48RE upgrades and order info

[sag2]

Here is info on the 48RE from the November Master Tech Reference Book. I have paraphrased a little bit.

Production of 48RE is scheduled for December. At that time production of the 47RE will stop.

Part of the design was to increase the durability to 150,000 miles. Major changes were made to the pump, valve body, friction material, gear train and park system.

The diesel pump has 20% higher capacity for adequate cooler flow. The addition of a seal ring to the reaction shaft allows the TC increased capacity for clutch engagement. The impeller hub on the torque converter is machined to accommodate the seal ring

The valve body provides increased line pressure in 3rd and 4th and during TCC operation, and allows the ability to engage the converter clutch in manual second gear for greater towing performance. The valve body also permits TCC engagement in drive-2nd gear for cooling protection, if the sump temp goes over 220 degrees. This may result in a change in shift quality, however.

The direct clutch in the 48RE's overdrive unit has 23 all new discs with friction material on one side only

The four-disc rear-clutch pack has been improved for greater durability. One disc was added to the front clutch for increased reverse torque capacity, and the overdrive clutch has five discs for non-HO and six for HO. The kickdown band lever ratio has also been increased.

The entire geartrain assembly is new, and all planetary gear sets and the overdrive carrier have a six pinion design. The front and rear carriers are made of cast iron, while the overdrive carrier is made of powdered metal.

The 48RE's drive shell is thicker for heavy duty reverse operation, and greater durability, and includes new thrust washers. To deal with higher vehicle weights, the park system has been enhanced with a new rod and wider park pawl. 2WD extension housing is designed to work with larger slip yolk.

Unlike previous automatic transmissions, the 48RE allows the use of an exhaust brake, too. It is a very robust transmission.



Sales says the trans is now available for order.

 

[robertyoke]

48re

My dealer told me no exhaust brake with auto trans will void the warranty . What gives? Is he full of S#@$%% or is he right? Will I need to lock the converter clutch with a "mystery switch" if I put one on? My other truck has a pac brake it's cool & with 75,000mi it has half the original front pad left. The 03 has Only 200 miles. Just received it 5/2

 

[DBVZ]

The 48re is e-brake compatable - designed for it and the lockup will coordinate with activation. As far as I know DC has yet to approve the e-brake with it, but it is being tested with the Jacobs Brake. The Pac Brake works with it also, controled by the ECM. The difference is the Pac is powered by an air compressor, and the Jocobs is powered by a vacuum pump. As for warranty, some people have assumed the approval will be given, and have put it on before approval. Others just want the e-brake so much they are willing to take their chances.

 

[Bill Stockard]

I helped another TDR member install a PacBrake on his '03 HO/48RE this past week. The PacBrake works very well in 3rd gear(Direct)as long as the torque converter stays locked up which is above 45 MPH on his truck. Now, if we can figure a way to keep the torque converter locked in 2nd gear... . maybe "fool" the PCM with a false signal that the fluid is over 220 degrees!



Bill

 

[Jeff Clark]

Bill, You guys didn't waste ant time, did you?

 

[Bill Stockard]

Jeff,



Yep, we din't lag around. Dick needed the brake on the truck before they leave and I wanted the install experience.



Dick and Judy are leaving next Tuesday for Minnesota, South Dakota, and Oregon for the summer and won't be back until October.



Bill

 

[PTMan]

You boys seem to know what you're talking about on the e-brake issue, so I'm going to jump on and see if you can help me out.

I'm driving a'96 12 valve 2500 4wd EC with 255,000 mi, and I'm about to make the leap into a new 04 3500 HO SRW 4wd QC LB for towing a new 5th wheel. BUT... adding an e-brake looks like a chancy operation as far as DC warranty is concerned.

I've spoken to ATS and they will supply a modified transmission and a Pacbrake installed and guaranteed by them for 100k, but they want a slug o' cash. I'm not sure I want to throw out the new 48re just yet. And I am not ready to give up the warranty to install a brake myself. So, my questions... 1. How much experience do you have with pvt installs of a brake re operation and oil heat? In other words are they working well. 2. How difficult is the install? I saw one member with an 03 who had used a "ats VB"... is that a valve body he installed? This could get complicated!

 

[Bill Stockard]

48RE/Pacbrake

PTMan,



So far with nearly 15,000 miles on his truck and towing a heavy 5th wheel trailer in the western US, the PacBrake has worked very well on long downgrades as long as the transmission is in 3rd gear with the torque converter locked. As long as the torque converter is locked, the PacBrake does a good job retarding, but as soon as the torque converter unlocks, the PacBrake is ineffective and he turns it off. There are no other modifications to the stock transmission. (I am speaking for the TDR member who I helped install a PacBrake on his '03 3500 HO/48RE. For our installation, see TDR Issue 41, pages 50-52)



As far as warranty issues with the exhaust brake and the 48RE, he will have to cross that bridge if he ever gets there. I think with prudent use of the PacBrake, performing regular service on the transmission, and not turning up the engine power, there probably won't be any problems.



I towed a heavy 5th wheel trailer all over the western US with a PacBrake on a stock '97 3500 with an automatic for nearly 100,000 trouble free miles before I traded for an '00 3500 6-speed.



I don't tow a 5th wheel anymore so I don't need an exhaust brake and one of the reasons why I traded the 6-speed for the automatic transmission in my '03.



As far as a PacBrake or any exhaust brake on a 48RE, it's your decision. I'm not saying do it or don't do it. The warranty issue, if there is one, will be between you and your dealer.



If you have other questions, send a PM. I'll be glad to try and answer them.



Bill

 

[PTMan]

Thanks Bill for that extensive reply. I think I'll go with a conservative position on the e-brake and wait til I need it for heavy towing in the hills. For now I'm willing to wait and see if the factory supports the brake with the 48re. I'm planning on getting a 33 foot Teton which is on the upper end of the tow capacity but don't think I'll be towing in the mountains much yet.

When I do, I'll just go with the brake install and try it to see. Sounds like y'all have had good performance with no problems. I don't plan to try to push the power up just yet either. One step at a time!



Max Wright

 

[Bill Stockard]

Originally posted by PTMan

... I'm planning on getting a 33 foot Teton which is on the upper end of the tow capacity but don't think I'll be towing in the mountains much yet.

Towing that kind of a load, I would give serious consideration to getting the 4. 10 ratio, if you haven't already.



Bill

 

[PTMan]

Bill... good point. Problem is I don't think much of the use of the truck will be actually towing. Most of the miles will probably be without a load. If it were to be used mainly towing, you're right... the 4. 10s would be the way to go. The Teton will likely set in one spot most of the time. It's not a "week-ender. "... more of a home, and I don't see myself dragging it all over the country.



I read in Issue 41 (most recent one) "Ranch Dressing" (pg 113) where John Holmes says they have had good results with the 3:54 axle pulling trailers over the hills. The loads may not have been as heavy as the Teton 33-foot model (about 13,000 lbs loaded,) but he was complaining about the fact DC had gone to 3. 73, which is lower geared than what he was used to. He bases his claim on the fact the Cummins develops its peak torque at a lower rpm and can handle the higher geared rear end. I don't know. My '96 has a 4. 10 and it's too low a gearing for over the road travel without a load. I'm figuring that with the extra power from the new HO engine the 3. 73 might be ok for an occasional load.

ANybody else have an idea?