1st gear lock up in a 47rh

Biohmmwv said:
My idea was to get the truck moving a little before lockup engaged.
I just don't know how many RPM it will drop with moderate throttle pressure.
2nd gear( which is the gear one usually takes off in while unloaded) in an NV4500 is 3.0 to 1 whereas 1st gear in the 47rh is 2.45 to one. It will take a little more forward movement before lockup can be engaged.
Basically, like slipping the clutch ( bad practice in a manual) longer in a manual transmission.



So, you're saying the transmission can't handle the power through it?
joefarmer, do you know where to get the instructions on how to do the mod on the valve body and can you share the info?
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Goerend makes a separator plate to allow lockup in 1st gear. The VB that I'm currently testing in my truck with a standalone transmission controller is a constant pressure VB from Goerend. At very cold temperatures, the lockup shuttle valve (CCSV) doesn't have enough fluid flow on the backside and will immediately, hydraulically engage TCC resulting in a stall. If you drive through it, the resulting violent 1-2 shift feels like someone is trying to kick your kidneys into oblivion. I installed this VB ~95 days ago and I now need to replace driveshaft U-joints.

turbo2387 said:
There is no such thing as 4th with nonlock up. That gear only exists when the converter is locked. 1,2,3,3lu,OD
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By manually applying 12v to either solenoid, you can make the following gears:
  • 1
  • 1 + lockup (bad idea)
  • 2
  • 2 + lockup
  • 2 + overdrive (bad idea #2)
  • 2 + overdrive + lockup (bad idea #3)
  • 3
  • 3 + lockup
  • 3 + overdrive
  • 3 + overdrive + lockup

On the stock 47RE and RH VB, you cannot disengage OD unless the lockup solenoid is also disengaged. Anything labeled (bad idea) has personally resulted in broken parts for me.
 
I know the pullers with crazy loose convertors, are locking in first(basically right off the line) however their tires are usually spinning, and they are on dirt, so it give a little forgiveness.
 
zstroken said:
I know the pullers with crazy loose convertors, are locking in first(basically right off the line) however their tires are usually spinning, and they are on dirt, so it give a little forgiveness.
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True. Driving on ice it had bigger issues but the jarring 1-2 shift wasn't one of them. LOL
 
turbo2387 said:
There is no such thing as 4th with nonlock up. That gear only exists when the converter is locked. 1,2,3,3lu,OD
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Funny.... early 47RH were non lockup. Just 1,2,3,4 and that was it. Lock up units appeared in 91-92.

Most 47RE's are programed 1,2,3,4 and TC LU from 95 and up. Now based on year and PCM programming it was usually 1,2,3, 3 LU in OD lock out. Then again there were more options with the 48's.

This was all based on how the PCM was programmed based on the year and I can't remember things on the older trucks. Been a long time since I have worked on them. But even on the older trucks you can see via scanner what the PCM commands and how the trans reacts.
 
raychem said:
Funny.... early 47RH were non lockup. Just 1,2,3,4 and that was it. Lock up units appeared in 91-92.

not that it matters to the original reason to this thread but the 47RH was in 94 and 95 trucks only. before that was 518's and before that 727's. 47re's are 96-2002.
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turbo2387 said:
raychem said:
Funny.... early 47RH were non lockup. Just 1,2,3,4 and that was it. Lock up units appeared in 91-92.

not that it matters to the original reason to this thread but the 47RH was in 94 and 95 trucks only. before that was 518's and before that 727's. 47re's are 96-2002.
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Just pointing out that the 727 were 3 speeds no OD and were from 89 to 91. There were A518 (47RH) 91.5-93 with lock up and overdrive. 47RE from 94-02. 618 is the 48.

You stated originally " every 4 speed 47rh or re i've every owned shifts 5 times not 6. cut the lock up wire and OD doesn't happen. you just get 1,2,3. fix the lock up solenoid and you get 1,2,3,3lu. fix the od solenoid and you get, 1,2,3,3lu,OD. making your 3 speed OD transmission feel like a 5 speed. "

I was just trying to clear this up. Every 47RH with OD and LU has 2 solenoids that run independently. If you cut the feed I would agree with what you are saying. Also, that the trans would shift with the TCC lock up into 4th which is what I understood would not be something as part of how the trans would shift. I would break parts. It would LU in 3rd but disengage to shift OD and then LU again.

Like I said above. It been a years since I have worked on a truck older than a 96... but from what I remember working on 94's. this was the factory shift pattern. Hell, I may still have a factory paper service manual around my office somewhere. All 3K pages worth.
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Biohmmwv said:
I was planning on using governor pressure for the speed signal since it is supposed to be about 1psi per 1mph. Then I would use the pressure ports to tell the Adrino if the a gear was already applied.

I like the 47rh as I could releasable have it computer "assisted" and still have a hydralic backup if there were a systems failure.
Reading comprehension is important Redrider2911
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On my 05 (48re), when drag racing I lock the converter in 1st gear at 12mph. I use an adjustable hobbs type switch on the governor pressure port to complete the ground circuit of the lockup solenoid. I have an "arming" switch to keep it from happening when not racing. I have made hundreds and hundreds of 1/4 mile passes this way. I have broken a part or two though... :doh:

Paul
 
No.

The A518 had overdrive, but no lockup in diesel applications.

Lockup in diesel Dodges was introduced in 1994 with the A618.

This was the 47RH from 94-96, and the 47RE from 97 onwards, which stayed in the Dodge Cummins application until the introduction of the 48RE.

The A618 (47RH) shifted 1,2,3,OD,LU in that sequence, from the factory.

Downshifting/kickdown from OD to 3rd only happened on a factory setup when the LU was disengaged, resulting in an unlocked downshift.


raychem said:
turbo2387 said:
Just pointing out that the 727 were 3 speeds no OD and were from 89 to 91. There were A518 (47RH) 91.5-93 with lock up and overdrive. 47RE from 94-02. 618 is the 48.

You stated originally " every 4 speed 47rh or re i've every owned shifts 5 times not 6. cut the lock up wire and OD doesn't happen. you just get 1,2,3. fix the lock up solenoid and you get 1,2,3,3lu. fix the od solenoid and you get, 1,2,3,3lu,OD. making your 3 speed OD transmission feel like a 5 speed. "

I was just trying to clear this up. Every 47RH with OD and LU has 2 solenoids that run independently. If you cut the feed I would agree with what you are saying. Also, that the trans would shift with the TCC lock up into 4th which is what I understood would not be something as part of how the trans would shift. I would break parts. It would LU in 3rd but disengage to shift OD and then LU again.

Like I said above. It been a years since I have worked on a truck older than a 96... but from what I remember working on 94's. this was the factory shift pattern. Hell, I may still have a factory paper service manual around my office somewhere. All 3K pages worth.
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Yes, generally 94 & 95 were RH, but I've pulled a 47RH from an unmolested 96

96-2002 were RE, but I've seen a couple early 2003 with 47RE instead of the usual 48RE.
 
There was some kind of weird split early on the 96. My Sept 95 built 96 model truck was an RE, but it looked like the trans had been replaced by the dealer with a later model RE. Mine also required an ECM flash to allow a lockup switch to function, but that was rare for the 96 RE's too. Factory was throwing leftovers together imo

Sent from my XT1575 using Tapatalk
 
ofelas said:
Yes, generally 94 & 95 were RH, but I've pulled a 47RH from an unmolested 96

96-2002 were RE, but I've seen a couple early 2003 with 47RE instead of the usual 48RE.
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The early 03 was 47RE with the 250HP Cummins. The 48RE came on the 305 hp version. I remember putting my order in for my 03 in January as the 48's came online. I do remember there was a delay in production so I did not get my truck till mid March.
 
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