View Full Version : 47RE to 48RE

08-19-2012, 03:03 PM
I am reading and trying to get a good idea, of what I should do. I am looking into getting a Dodge soon, and I plan on building it up slowly, and I am applying knowledge as I learn and when I can. As I have been reading it seems like the 48RE is the better transmission of the two, and it seems like it would be a perfect transmission, as long as it is upgraded. Well what I plan on doing if the truck I get, is a automatic, is finding a 48RE, and build it, and save it for when I really start doing up the truck. What I need to know is

1. Can you swap in a 48RE in place of a 47RE, with no major problems to solve? Such as wiring, or a TCM?

2. Are there any pieces from a 47RE that I should grab to use in a 48RE?

I ask all this cause I can not find the info I need, and I want to use the best possible. I was also told the 48RE comes with the better transfer case on it, and I figure the better off I would be if I use a better setup.

Thanks guys!

08-19-2012, 04:00 PM
do some reading boy

Start here : 47RH/47RE Info/Do it yourself thread - Competition Diesel.Com - Bringing The BEST Together (http://www.competitiondiesel.com/forums/showthread.php?t=100506)

Knowledge is like *****...

what happens if you dont persue it.....

08-19-2012, 04:33 PM
Sounds like he has been reading and has valid questions...

And we all know how useful the search can be.

Epically post by a dumb phone.

08-19-2012, 04:48 PM
Rebuild the 47re with all 48 internals and then you will have no wiring issues

08-19-2012, 07:16 PM
Thanks crackerman, and SHughes. I have been reading most yesterday evenign and all day that I could, and just wanted to get down to the bare bones of it. So just grab a 47RE, swappin 48RE parts.... I like that idea, I read a ton on doing custom work to fit more clutches and oiling modifications to support it, but that was all for the 47RE, I assume it can also be done to the 48RE?

08-19-2012, 07:20 PM
What do you want so bad in the 48RE?


08-19-2012, 07:28 PM
I got rid of my 47rh for a 47re with 48 internals for my 4 digit sleeper build.

08-19-2012, 07:35 PM
It's been a while, but the biggest difference is a planetary, pump and vb, and some bearing and bushing changes to the 48RE...correct?

I agree the 48RE has some things going for it, but is it worth finding all the guts for a non max effort build?


08-19-2012, 07:45 PM
It just depends what your doing with the truck and how much power you want to make. I still have factory 47re parts in mine, besides the input. The 47re parts are pretty stout IMO

08-19-2012, 07:51 PM
Well I am hoping to do a 'Sport' conversion to the truck, and just make it look.. simple? I guess simple is the word, and I am wanting to hit the 600/700 hp range. Maybe mre maybe less, just depends on what I end up with and such. And I am just trying to do some planning ahead so when I get it, I know what my next step will be. I am hoping for a truck with a P-Pump already in it, or a 24V cause I already have a P-pump and just work up to doing a 24V P-Pump conversion. As for the use, its going to pull a sled twice a year. Once at a Test and Tune and once at the Fair. Other then that its gonna be driven to work some, and going to be my sports car.. So I am wanting something rounded, I also want to do as much custom work as I can, so I am not accused of having my main parts guy build it for me.

08-19-2012, 08:23 PM
You really shouldn't need to go scrounge up a bunch of 48RE parts then....IMHO

I had a 48RE VB in mine to get the setup I wanted, but the rest of the parts were 47RE....held 600hp at 7800lbs....I heard the current owner of that truck finally fragged the tranny, but god only knows what he did to it.


08-19-2012, 08:56 PM
Sig600, was your Valve body a race body where it allowed you to lock 1st and 2nd gear? Cause I want to be able to do that.

And may I ask why a 48RE VB in a 47RE? Just curious so I know why you did it. And I wanna build it up so that way if I ever have a wild hair and do something big, I can and now worry about my tranny, you know over build it and forget it kind of thing, but I thank you for the info. Now just to get back to reading about clutch combinations.

08-19-2012, 09:32 PM
Mine was a single disc converter setup, running 210psi line pressure when it locked up....the 48RE VB, as i understand it, drives a bit nicer with the higher pressure. Yes, I could lock it in 1st....can't say I would have another one built that way for the street....if you mess up and lock up 1st gear and then hit 2nd, it is VIOLENT....and very much bad.

Keep in mind, my tranny was build in early 2007....there have been a LOT of changes in the tranny world since then.


08-19-2012, 09:47 PM
Well I mainly want it so I can lock in 1st for when it snows around here and I need to get up my grandmothers driveway, lock into second for different reasons, I dont plan on shifting, thats why you put it in drive isn't it? lol. Sig600, I appreciate your info. How do you change your line pressure?