What to look for on a bad 65RFE valve body

[Burla]

Congrats Ender, I'm sure you learned a lot through the process. And I almost never heard of a transmission shop just changing a solenoid pack, they usually do a rebuild at that point with your miles, and it is at least 600 just to drop the tranny, so I'm sure you saved a lot of money, if you get another 100k miles plus, it was well well worth it.

 

[TheEnder]

Congrats Ender, I'm sure you learned a lot through the process. And I almost never heard of a transmission shop just changing a solenoid pack, they usually do a rebuild at that point with your miles, and it is at least 600 just to drop the tranny, so I'm sure you saved a lot of money, if you get another 100k miles plus, it was well well worth it.

I completely agree, thank you. Now, it’s just on to be repainted, get body work done, and get her looking new again.


Sent from Blue Onyx

 

[TheEnder]

Just a question, do any of you maybe have an answer to the truck always throwing a P0934 code whenever the line pressure booster isn’t on? I’d like to keep it off to avoid any issues in the future - but whenever i take it off it sends a CEL for P0934, which is Hydraulic Fluid Pressure Sensor Circuit Low.

Just a question, if it’s okay to have it on without risking issue i’ll keep it off, but i’d like to take it off.


Sent from Blue Onyx

 

[Hemi395]

Just a question, do any of you maybe have an answer to the truck always throwing a P0934 code whenever the line pressure booster isn’t on? I’d like to keep it off to avoid any issues in the future - but whenever i take it off it sends a CEL for P0934, which is Hydraulic Fluid Pressure Sensor Circuit Low.

Just a question, if it’s okay to have it on without risking issue i’ll keep it off, but i’d like to take it off.


Sent from Blue Onyx

Did you have it on when you first reconnected the electrical connector for the SP? It might be thinking with the booster it's "normal" and without out it's "low"

 

[TheEnder]

Did you have it on when you first reconnected the electrical connector for the SP? It might be thinking with the booster it's "normal" and without out it's "low"

I first had it a few months ago before anything was done with the truck, along with a jump in RPMs before each shift, and it turned out to be the negative battery terminal giving me the problems, and then the battery had problems charging right after, which through a “Battery Low Voltage” error in the Instrument Cluster.

Last night i disconnected both terminals and cleaned them with sandpaper, and took out the PCM/TCM fuses to let the circuit drain and (knock on wood) the code went away with no booster installed.


Sent from Blue Onyx

 

[BadHemi2014]

Hooray! So happy for you, fingers crossed that she works perfectly for a long long time!

P.s. mine drank close to 8qts with a pan drop and filters changed, same tranny.

 

[TheEnder]

Hooray! So happy for you, fingers crossed that she works perfectly for a long long time!

P.s. mine drank close to 8qts with a pan drop and filters changed, same tranny.

Thank you! I hope you have great luck with yours if anything goes wrong (i hope not). This one took 10 to get her filled to the correct level.


Sent from Blue Onyx

 

[TheEnder]

Did you have it on when you first reconnected the electrical connector for the SP? It might be thinking with the booster it's "normal" and without out it's "low"

The code came back, and yes, i did have it connected. I’m gonna put it back on and leave it.


Sent from Blue Onyx

 

[Burla]

I would check the fluid again after a short trip.

 

[TheEnder]

I would check the fluid again after a short trip.

I just checked it and it’s above the full mark. Yup.


Sent from Blue Onyx

 

[TheEnder]

I’ve found some, interesting to say the least results as of today regarding the LPS.

I disconnected the Line Pressure Booster from the Pressure Sensor and left the LPB attached to the trucks harness, and it drove how it has for the past few months since i got the LPB, which isn’t great when you’re expecting *that* much crisper shifts out of it, and there were no codes for the LPS even though the booster was literally disconnected from it.

When i got the booster the first time, the original Mopar OEM LPS broke, so i got a Power Tech (or torque, i forgot) LPS and installed that, and immediately had issues which are still continuing to this day, which is making me think that the Power Torque LPS isn’t compatible with the truck.

These issues didn’t start until the original Mopar OEM LPS broke.

Issue #1: Transmission “disengaging” after 6 to 5th downshift

When the trans tries to make the 6 to 5th downshift, it’ll do what looks like unlocking the torque converter, which makes the engine free to spin all the way up to the torque converters stall speed of 2100 RPM, for around 2 seconds. This doesn’t happen all the time, probably more around 75-80% of the time.

Issue #2 Engine surging upon full throttle

This is an issue that also sometimes occurs, which happens when wide open throttle occurs and the trans downshifts from let’s say from 6th to 4th, it’ll downshift correctly, than half a second later the engine jumps around 500 RPM and everything’s “good” from there on.

Issue #3 Incredibly Soft Shifts in higher RPMs

When you get off the line, the truck lightly jolts from 1-2, it doesn’t jolt from 2-4 but it takes around 2 - 3 seconds to complete the shift from 2-4, and the same from 4-5, and from 5-6.

This is the end of the issues from when the LPB is installed.

Without the LPB installed and the trucks harness being directly connected to the LPS, these things occur:

Issue #1, Check Engine Light, Code P0934: Hydraulic Pressure Sensor Circuit Low

Issue #2, Engine surging between each shift

Issue #3, While the transmission is in the middle of shifting, the engine “halts” in between shifts and then completes the shift.

I’m waiting for my Mopar OEM LPS to get in, but i’m wondering if anyone has any insight on this, as i think that the LPS isn’t “supported” under the 65RFE harness, or 65RFE TCM.


Sent from Blue Onyx

 

[Burla]

I don't think the 2013 pcm is locked, dunno for sure, but it sounds like a real tune might be the way to go. However, with a trans pressure tune you will actually need a new valve body with updates, at a minimum a gasket, but probably a plate would be better. @Hemi395 is that 2013 is locked pcm? Easier to do if it is unlocked. A tune will increase line pressure by a lot, you cant do it with an old stock VB.

So in general is the trans working good right now?

 

[TheEnder]

I don't think the 2013 pcm is locked, dunno for sure, but it sounds like a real tune might be the way to go. However, with a trans pressure tune you will actually need a new valve body with updates, at a minimum a gasket, but probably a plate would be better. @Hemi395 is that 2013 is locked pcm?

I think they started locking the PCMs in 2015, not very sure, but all i want right now is to get rid of that code. I wanna see if i can be sure that the internals of the trans is good, (which they should be, no metal any of the times i’ve dropped the pan) but just to be sure. I’m aware about the updated VB, and i’m looking into one (and actually looking harder this time)


Sent from Blue Onyx

 

[TheEnder]

I don't think the 2013 pcm is locked, dunno for sure, but it sounds like a real tune might be the way to go. However, with a trans pressure tune you will actually need a new valve body with updates, at a minimum a gasket, but probably a plate would be better. @Hemi395 is that 2013 is locked pcm? Easier to do if it is unlocked. A tune will increase line pressure by a lot, you cant do it with an old stock VB.

So in general is the trans working good right now?

It’s working nicely, i just wish that it didn’t “slip” from 6 to 5.


Sent from Blue Onyx

 

[Burla]

What is the current state of the transmission, I can't read between all of those lines.

 

[RedSRT4Me]

I think they started locking the PCMs in 2015, not very sure, but all i want right now is to get rid of that code. I wanna see if i can be sure that the internals of the trans is good, (which they should be, no metal any of the times i’ve dropped the pan) but just to be sure. I’m aware about the updated VB, and i’m looking into one (and actually looking harder this time)


Sent from Blue Onyx

Correct. Late 2014 models and all 2015 up have locked PCM

 

[Burla]

I believe overdrive clutches go first, when they tend to go. Might rewatch the sun coast dudes.


So the other suspect would be VB pistons and/or leakage. But you really feel like breaking it open again?

 

[Hemi395]

Did some research on the P0934 code, its a circuit code which is more than likely either the sensor itself or a wiring problem. Heres some info:

Set Condition: This DTC will set when the monitored Line Pressure Sensor voltage is less than or equal to 0.35 volts for 0.18 of a second.

I would ignore the PCM as the problem simply because thats on the bottom of every possible cause list for just about every problem lol

Probably a good idea to follow the wires to that connector as far back as you can and see if theres any spots that are rubbing on anything.

 

[TheEnder]

I believe overdrive clutches go first, when they tend to go. Might rewatch the sun coast dudes.


So the other suspect would be VB pistons and/or leakage. But you really feel like breaking it open again?

I replaced the pistons/accumulators/springs a week ago, and the gist of the long rant i went on is that the truck isn’t reading anything from the hydraulic pressure sensor at all, and it shifts the same as it does “normally” without the pressure sensor being connected. which makes me think the lps is bad.


Sent from Blue Onyx

 

[Burla]

It’s working nicely, i just wish that it didn’t “slip” from 6 to 5.


Sent from Blue Onyx

slipping on the downshift not the upshift?