5R55E Woes

[imp]

If i have already removed the transmission is it too late to get the codes? I had no overdrive with the light flashing. Greyish fluid upon teardown nothing in the clutch packs or sprags worn.

@nathan mayden
I should think not, since codes are stored in the PCM. imp

 

[96eb96]

96 is likely referring to the GEM test protocol in ForScan. During which you follow the on screen prompts and the software will activate the shift encoder.

I can control the 4wd clutch lockup using the pc version. Theoretically I could get a second adapter with a Y cable, set another computer in listen mode, log the commands, and write an app to control the 4x4 system.

 

[drdoom]

Nice! Good computer skills, 96! Quite interesting.

 

[RandomNerd2000]

Alright, so I have an update, my fluid looks fine, and to the TCC solenoid, it's showing no voltage in the app, is that the voltage going to it or through it? It's going through all the gears, but when it gets there, the TCC solenoid isn't doing anything.

 

[BrooklynBay]

Check the internal wiring harness, and the bulkhead connector with a multimeter.

 

[RandomNerd2000]

Checking the bulkhead connector, what wire(s) am I looking for? As for the internal wiring harness, checking it, what goes into it? I'm brand new at working with transmissions and I'm making sure I don't screw it up since it's my DD

 

[96eb96]

Alright, so I have an update, my fluid looks fine, and to the TCC solenoid, it's showing no voltage in the app, is that the voltage going to it or through it? It's going through all the gears, but when it gets there, the TCC solenoid isn't doing anything.

tcc shows a percentage on mine. did you press the play button? try some other pids like fuel trim.

 

[imp]

Alright, so I have an update, my fluid looks fine, and to the TCC solenoid, it's showing no voltage in the app, is that the voltage going to it or through it? It's going through all the gears, but when it gets there, the TCC solenoid isn't doing anything.

@RandomNerd2000
Please understand, voltage may be going "to it", but not "through it". Voltage is Electrical Pressure existing bertween two points: the ends of the solenoid coil. If the voltage is there, between those two points, it causes a CURRENT to flow through the coil, unless the coil is damaged. If the app you mention says no voltage is being applied to the solenoid, something is preventing that from happening. No voltage applied could be caused by a number of things: Transmission Fluid Temperature Sensor failure is one. TCC will not engage until temp. reaches a certain level. If what your app is saying is correct, the solenoid is not at fault. imp

 

[RandomNerd2000]

@96eb96 I'm using Forscan, and yeah I've mashed the play button, also looked around and tried out other PIDs.

@imp That's what I'm trying to say basically, I have no voltage being applied to the solenoid, I watched it go through the five gears and it never applied any voltage to the solenoid. I will take a look at the Transmission Fluid Temp Sensor and report back with what I find, I'm trying to avoid just throwing parts at the problem with no avail

 

[imp]

@RandomNerd2000
I hear you. Buying one part after another is a rough course to follow. What I fail to be knowledgeable about, is just which components is the PCM capable of detecting faults with? For example, the Trans. Fluid Temp. Sensor may never achieve telling the PCM "OK, temp. is up, lock up the TCC". TCC never engages until temp. is up. imp

 

[RandomNerd2000]

The sensor for the trans temp is working, it's having no issue reporting temp, I haven't had a chance to test further, such as unhooking the battery to see if I can reset the truck, but I'm going to, also been having some moments with the bluetooth connection with my phone, figure it's just my phone

 

[nathan mayden]

Can someone explain how oil gets to the tq for lockup? I have one of these apart and I don't see it.

 

[RandomNerd2000]

Alright, so, another minor update, the trans temp is working, unhooked the battery for a bit, and it did proceed to enter lockup after being disconnected 10ish minutes, one time, when I slowed down, and sped back up, it wouldn't do it again, showing no activity from the TCC solenoid again. It's shifting perfectly smooth through all five gears, the fluid is red, and the trans fluid temp sensor is working. That's a basic summary, now where do I go?

 

[imp]

Can someone explain how oil gets to the tq for lockup? I have one of these apart and I don't see it.

@nathan mayden
Since the fluid pressure which engages the TCC is turned ON by a solenoid within the transmission case, it is apparent it is delivered to the TCC via a hole within the input shaft. This is how, typically, oil is delivered to the various clutch apply pistons. This fact explains why shaft thrust dimensions must be kept within design limits: small holes must line up axially between shaft and it's surrounding part to allow oil flow from one part to the other. Move one or the other far enough (like from a broken thrust bearing), and the clutch being supplied will not apply,. no oil. imp

 

[imp]

Alright, so, another minor update, the trans temp is working, unhooked the battery for a bit, and it did proceed to enter lockup after being disconnected 10ish minutes, one time, when I slowed down, and sped back up, it wouldn't do it again, showing no activity from the TCC solenoid again. It's shifting perfectly smooth through all five gears, the fluid is red, and the trans fluid temp sensor is working. That's a basic summary, now where do I go?[/QUOTE]
@RandomNerd2000
If I'm up to date here, you have not replaced the solenoid, is that correct? You have not found it to be energized when it should be? How did you determine that? At the solenoid itself, there are two wires. One is HOT (12 V) in Start and Run, the other goies to the PCM. PCM grounds that other conductor to turn the solenoid ON. The solenoid can be heard to click, from under the vehicle, if you ground the appropriate connection with KEY ON. Alternative method is to measure solenoid coil current. All of this obviously side-steps looking at the PIDS. Old fashioned.

My guess is, the solenoid may be sticking, that is, has become intermittent. OR, the TCC is intermittently engaging. OR, the PCM is faulty (unlikely, but it happens occasionally). Since the 5 gears seem OK, you CAN drive it as long as you wish with no TCC, and buy 4-5% more gasoline. imp

 

[RandomNerd2000]

So I've done some research on this, and I've learned a great deal, and if I'm not wrong in my logic, I'm down to the TCC solenoid, the EPC, or the fluid itself, sound about right? It's striking me as a EPC issue since it doesn't show any TC solenoid activity on the live data. Input is appreciated.

 

[BrooklynBay]

You could check the pressure of the EPC solenoid with a 0 - 300 PSI test gauge. The pressure port has a removable plug.

 

[RandomNerd2000]

So, even though at the moment I don't have a pressure gauge to test the EPC with, I did look at the data on it. Idling is 51 PSI, partial throttle, it goes to about 60 and shifts, full throttle it gets up between 65-70 and shifts, and applying the brakes going down the road it runs about 51. I did notice that from 55-70 MPH, I have no change in pressure showing on the EPC, which I find unusual, shouldn't the pressure go up as the speed increases, because it's showing no change, which makes no sense to me

*Edit* There a chance that this is a valve body issue? That keeps coming to mind for me, the fluid isn't bad looking, which tells me the TC is good.

 

[BrooklynBay]

A lot of times it's a valve body gasket issue. The bolts get loose near the EPC & TCC solenoids since they are modulated, and not simple on/off devices like the other solenoids.

 

[RandomNerd2000]

Well I have absolutely NO records for any transmission work outside of fluid and filter changes, so I doubt that it's ever actually had any updates or anything done to the transmission.