47RH Electronic Conversion
 

So i am getting tired of my transmission’s inconsistent shifting between temperature changers along with other issues. Like the throttle cable being tight enough to raise the line pressure like i like but then having issues with shifts hanging or random harsh kickdowns when it shouldn’t be. Etc. There’s a lot to be desired.

So i like DIY type projects where i get to use some creativity as well as really get to know a system. So i am thinking about converting my 47RH over to pretty much full electric control. i know a few people will be like, why not just swap to a 47re or 48re, and better yet; buy a standalone controller from a vendor. WELL. I already have this transmission and the options available leave much to be desired. My biggest complaint is the lack of TCC lock and unlock control. Which i will share my ideas as this progresses. My other issue is that with controlling the shift points by the electronic governor pressure regulator, it can still be finicky with temperature changes and lacks direct line pressure and throttle pressure control.

So my thought is (simply put), adapt some OE style dump solenoid valves (like what is used for the OD and TCC) to the governor plug side of the 1-2 and 2-3 shift valves. Then use a GM pressure solenoid valve to control line pressure completely independently. Originally i was going to build an Arduino to control this, but then i found that MegaSquirt has actually came out with a MicroTcu board that is TunerStudio compatible and should be able to do everything i want for a decent price.

Sorry for the long intro, but what are your initial thoughts?

initial thoughts...


your 47RH isn't built correctly

Was thinking the same thing

I’m not the only person who has been unsatisfied with the lack of tune ability of the 47RH... where are you getting this outlandish idea that i don’t understand how to build a transmission? It sounds like neither of you have ever studied a hydraulic circuit diagram of these transmissions or even traced them out manually. If you have, you would know the pitfalls of the design.

Because for 5 years I drove a 47rh trans that was built correctly, never had one issue didn’t matter if it was -30* or 110, towing or at the strip, cruising or stop and go. Shifted perfect, lock up was consistent only problem I had was twisting input shafts. If you want to fix your issue I would suggest sending the valve body at least out to a reputable shop. I never said you built it wrong but if you did build it then yes I’m saying you did it wrong

I'm not going to argue my intelligence with a keyboard hero who likes to run is mouth. but if early OD shifts are your concern as many times that's the complaint a manual OD switch used for towing purposes or keeping on top of a large turbo solves tons of issues. Assuming your transmission is actually assembled properly with parts that talk to each other correctly, but what do I know about anything?

So in your "professional" opinion you are going to try to tell me that fluid temperature has absolutely no bearing on shift points? You do know how the mechanical governor works right? If I wanted my transmission to shift like stock there wouldn't be any reason to upgrade at all, I don't want it to shift like stock. I have already swapped to v10 governor springs and done some other modifying there to raise my shift points. I am also maxed out on line pressure with my modified Transgo shift kit, everyone (or at least I though everyone) knows that on a 47rh maxes out at about 175psi and will also cause early low throttle shifts but super late on throttle shifts due to how the throttle pressure and kickdown pressure circuit is designed. Nothing wrong with my lockup at all, it locks and unlocks like it was designed to... but I along with many others do not like how it is designed to operate; hence why so many people add a torque converter lockup switch. If I thought I would be happy with how a vendor would program my truck to shift, then I would be going that route.

Its mechanical. it takes a smart person to tunes real things. its not plug and play.

You obviously didn't read the huge paragraph explaining WHY I want to do this project in the first place. A. If I wanted to manually control OD then I would simply have put in a switch like you are suggesting. B. If this was indeed a current concern of mine, I would not be using a manual switch but instead I would manipulate the TPS voltage and/or go to a stiffer spring in the 3-4 shift valve.

Its just surprising to me that I start a technical thread that is way more in depth than just "properly rebuilding a transmission to get it to shift the stock way", and you immediately come back with a nonhelpful response of "your transmission isn't built right".

Smart ass. Funny coming from someone who just a couple months ago was having trouble figuring out how to tune his AFC!! "At what point does the AFC Foot pass the fuel plate and let it take over?..." Genius, it is different on every setup depending on what your max allowable rack travel is, what fuel plate you are running, where your fuel plate is set, and where your AFC housing is set. That's why no one wasted the time attempting to give you the "plug and play" answer you were looking for! But what do I know, I'm not happy with how the 47rh or even 48re are designed to shift as well as the lockup patterns. :blahblah1: This thread is obviously not about Plug and Play solutions (unless someone could prove to me that exists for my desires) so take your unhelpful and off topic insight elsewhere.

Here's my take on Dodge automatics...having driven a tuned 68RFE, a 47RE with all the goodies, and a 47RH with a mild build...if you want it to shift when you want, and never have to mess with goofy shift points once you have it setup, then swap it for either an NV5600, or trade the truck for a Duramax/Allison and you'll actually have something that shifts decent.

I was NEVER happy with shifting in any Dodge automatic, PERIOD. The 68RFE was best once I got the MCC tuning and played with shift points, but I could still never get what I wanted between towing and empty. And none of the 47/48 series transmissions ever did anything close to what I wanted, so I shifted them manually towing and at the track. When you're modifying everything so far past factory, you can't expect everything to work together perfectly.

Just my $.02
Chris

I would not say my transmission shifted like stock, it was extremely firm and at a very late high rpm shift. I didn’t build it, just had a shop do it. I do believe they changed the lever on the throttle valve to adjust the proportion. Does fluid temp effect a mechanical circuit yes, I work in hydraulics, yes I can trace a schematic, yes I understand how this works... however, I do truly Believe you are trying to re invent the wheel here. It’s been done, and proven, while you keep trying to redo it. Swallow the humble pie and get it professionally done. As I stated before that trans was in negative 30 and 110 temps. Did just fine.

Nothing I like better than that slow lethargic Allison shift

Thanks for the opinion Chris. It actually shows others agree with me on the crappy shift logic! This was my first Cummins, and in all honesty if i would have been able to tell the future i probably would have swapped in an Allison from the get go. In my setup and with where I am at, that would just require so much modification that it isn’t funny. Lol l think for money, time spent, and modifications i would have to make to do the swap; i believe i am further ahead to do my shift valve/shift solenoid modification... and i believe it can help others as well.

Nothing I like better than changing head gaskets on my own when my Dodge is under warranty, but since I use my truck to make a living, I'll drive what runs.

Chris

I'll never put an Allison behind a mechanical engine...too hard to tune, same as the no shifting 47's.

Chris

I owned one duramax. Ride was awesome, interior was great, very slow shifts, and bad fuel economy made me sell it

I am a professional..... At modifying things to work how I want. If you haven't gathered already, I don't just want a extremely firm and high RPM shift. I am by no means attempting to recreate the wheel. I want control of line pressure rise independent of shift RPM rise. I want the torque converter to automatically lock in 2nd, unlock for the shift to 3rd, lock again, unlock for the shift to 4th, and then lock again. And like wise, I want it to do the same on downshifts when on the brakes. I want a couple presets I can change between so that when I go to the track the torque converter will lock in second and stay locked through the shifts to 3rd and 4th and then unlock when I hit the brakes for the downshift back to 3rd at the end of the track and then proceed like described above. Like I said, and Chris has said; the Dodge transmssions shift logic has left a lot to be desired. Additionally, no vendor (as far as I have found) offers that kind of shift logic for the Dodge transmissions which is astonishing to me. And even if they did, the cost would probably be so high that I would rather make the system myself for 1/4 the cost.

I forgot to mention the possibilities of fixing a tiptronic or paddle shift setup to my truck as well so I CAN manually shift it if I want.

Muldoons has already done that