Tell me about the 48re transmission?

[rjohnson916]

Tell me about the 48re transmission. I’ve had my truck 1. 5 years, it’s great and I love it to death but. I again screwed up and got an automatic where I’ve previously always owned a stick shift. Anyhow I’ve driven/ rented many of slush-boxes and to my experience I’ve yet to drive anything automatic like the 48re in our 3rd generation CTD’s. It seems or appears this transmission has pre set and determined shift points, hypothetically since I’m not in or driving my truck 30 mph, 40, 50 respectively. This transmission waits for the truck to get to the aforementioned respective speed and then shifts??? Annoying and weird. I’ve rented just for comparison Pontiac G6 V6 recently, the cars transmission would shift throughout the gear range quickly if there is little throttle input, also there appears to be no indicated speed criteria but more of a load and rpm so to speak. The trans in the Pontiac is how I remember an true automatic to be like. The 48re doesn’t care if it’s light throttle or WOT it still shifts at or near the same speeds. Anyone else notice this?



-Ryan

 

[y-knot]

You really could not have picked a more different type transmission then that of which you did. Truck transmissions are set-up completely different then car trany's, they have to be look at the differences. The truck first off weights almost twice what the Pontiac weights, it is made for towing very heavy loads and hauling. The steering has been slowed down to accommodate safe towing, and everything on the truck is over-sized so it can complete it's mission. By contrast, the Pontiac has a fast steering set-up, small high revving motor, that makes a small amount of torque. You could legally place the Pontiac in the bed of the truck and haul it to the garbage dump, thats the difference. The Cummins is a slow revving engine, that makes huge amounts of torque at low RPM's. The transmission really suffers under this sinareio. Where the car winds up and shifts in the 3500-4500RPM range, you get a better shift because the car, engine and transmission are all moving faster and under a lighter load, the gearing can also be better spaced for a better, smoother transition. Weight has a lot to do with it to, the car is much lighter, so the shifts are not so noticeable, they can be smoother and less notchy. When a Cummins equipped truck shifts, it's at a much lower RPM, which causes it to be more brash. You have a small window to work within, most trucks will not rev past 2500RPM. Also our gears are not as close, so when we shift they tend to be felt more, and the engagement is definitely harsher. It has to be, we are holding back 600+ FT/LB torque, which is 4 times what the Pontiac probally makes.

A more useful comparison would have been to ride in simular trucks but a different manufacturer. Also, todays automatics are truly nothing like the auto's of yesteryear. Now days we have 5-6 and even 7 speed automatic transmissions. The shifting is very smooth and precise, with many having the ability to manually shift through the gear box like a F1 racer (paddle shifters) sequentually up or down at a touch of a button. I too was once a strarch manual transmission guy, but today I think the nod has to go tho the automatics.

 

[RBollengier]

I bought the automatic because of the narrow torque and power band. Since most of my driving is to work it seemed I was shifting every few truck lengths. Both of my Jeeps are manual, but they rev freely to 4k without much drama.



But mine does shift at the same points most of the time at part throttle. Especially the torque converter lock up. 50 no more no less. All of the shift points change however with more throttle. Not much and a lighter throttle they are about the same and I could see where you would think they are. I think it's the narrow power band. Not much to play with so the shift points look preprogrammed. Mine doesn't pull off spot lights very well until it gets moving. Sometimes that can cause drama if I have to pull out in front of traffic.

 

[Hoefler]

Try running in the tow/haul mode. When you accelerate, do not push the pedal all the way to the floor. Push down about half way and just gradually push it the rest of the way. I am not sure why that makes a difference, I am guessing that it allows the turbo to spool up and not go into defuel mode. This woks at trying to pass on a two lane. It is hard to do, but by not flooring it, it takes off real well. This transmission is different than any auto I have ever driven, from the TH 350 in Gm to the Allison 4 - 7 speeds found in school buses and fire trucks. I tow 6,000 to 8,000 every day, and on occasion 13,000 to 15,000, let me say, it has been a learning experience. I drive with the tow/haul engaged all the time, it will lockup sooner and stays engaged to a slower road speed when slowing or going down hill.

 

[coobie]

Tell me about the 48re transmission. I’ve had my truck 1. 5 years, it’s great and I love it to death but. I again screwed up and got an automatic where I’ve previously always owned a stick shift. Anyhow I’ve driven/ rented many of slush-boxes and to my experience I’ve yet to drive anything automatic like the 48re in our 3rd generation CTD’s. It seems or appears this transmission has pre set and determined shift points, hypothetically since I’m not in or driving my truck 30 mph, 40, 50 respectively. This transmission waits for the truck to get to the aforementioned respective speed and then shifts??? Annoying and weird. I’ve rented just for comparison Pontiac G6 V6 recently, the cars transmission would shift throughout the gear range quickly if there is little throttle input, also there appears to be no indicated speed criteria but more of a load and rpm so to speak. The trans in the Pontiac is how I remember an true automatic to be like. The 48re doesn’t care if it’s light throttle or WOT it still shifts at or near the same speeds. Anyone else notice this?



-Ryan

If you change the torque converter and Valve body,the 48re transmission it feels like a different transmission. I went with the goerends brothers setup and love it,it shifts smoother and more percise. I also can tell it puts more power to the rear wheels. coobie Oo.

 

[lethal injection]

I dont like my 48re... . IT SLIPS ALOT!!!!!!!!

 

[JPereira]

48re

My CTD is the first diesel and turbo vehicle I have ever owned. The transmission in the Dodges are definately different than anything I have ever owned. I think it is a strong package but agree that how and when it makes shifts is strange and frustrating. Lockup for top gear on my 3. 73 geared truck is 50 mph. That does not matter if it is babied or under moderate throttle.



I am patiently awaiting for TransGo to come out with a shift kit for the 48RE and I will be trying that. I had searched around on this forum and others have had good success with this Brand on previous years. I have used this type of kit on many gas vehicles over the years with good results. I am not sure if this type of package is the best choice for the heavy powerful vehicles but it will most likely be the next thing I try.



www.oregonperformancetransmission.com was a vendor I found on eBay and has been responsive in answering questions I had.



I would love to buy a billet aftermarket transmission but the costs are just not something I can justify. I don't work my truck hard and this transmission would probably last as long as I want the truck. I just don't like how it shifts and want that to change.



Sorry for the long post, many thoughts ame to mind...

Jeff