5R55E question

[tkmitchell]

I am trying to get my transmission in working order. I have what is hopefully a simple question. What are the appropriate values for the Overdrive Drum Speed Sensor? My transmission is not working and in using a scan tool that can show live data the ODS has what seems to be strange values. I replaced the sensor and same thing. There may be an electrical issue, but I am curious as to what this thing should be reading. Should the values correlate to the input shaft speed, or the output shaft speed?

Right now, when it is idle input shaft speed is close to RPM. Output shaft speed is 0, what I expect because it is not moving. ODS show over 4000, not what I expected, or is it?

 

[RonD]

Your scanner is showing a sensor that does not exist on the 5R55E, which is not unusual, scanners are universal so need PIDs for several vehicles
PID = packet ID, the scanner sends a request for a specific PID and then displays that data regardless of what it is, using its formula for the PID data
You can see more here: https://en.wikipedia.org/wiki/OBD-II_PIDs
But there is alot more to it, lol

In 2001 and up 5R transmissions there are 4 sensors
TSS - turbine shaft speed
ISS - intermediate shaft speed
TFT - fluid temp
OSS - output shaft speed

2000 and earlier didn't have ISS or OSS(VSS was used)

On earlier 5Rs there was a sensor on top, by bellhousing end of transmission, but it was never used

 

[Dirtman]

Stop looking at data and focus on the symptoms.

 

[Dirtman]

I'm serious here. I'm guilty of it, I look at live data too much and ignore the physical symptoms. The live data is an amazing resource but some scanners don't give you good data, sometimes the data is skewed by other issues, or sometimes you're simply misinterpreting the data.

When you wanna diagnose a problem start by explaining the symptoms experienced. Then move from there.

Saying "my scanner says this, and I think it should say this" is not useful in most cases, it's just invalid data. Is the transmission throwing codes? Is it not shifting? Not moving? Harsh shifts? Things like this are much more valuable to know in order to help.

 

[RonD]

Best scanner/computer you got is your own brain


If you look and see a flat tire you don't grab the tire pressure gauge FIRST, lol, well maybe some do, but the issue is not the exact pressure in the tire at that point

 

[tkmitchell]

Your scanner is showing a sensor that does not exist on the 5R55E, which is not unusual, scanners are universal so need PIDs for several vehicles
PID = packet ID, the scanner sends a request for a specific PID and then displays that data regardless of what it is, using its formula for the PID data
You can see more here: https://en.wikipedia.org/wiki/OBD-II_PIDs
But there is alot more to it, lol

In 2001 and up 5R transmissions there are 4 sensors
TSS - turbine shaft speed
ISS - intermediate shaft speed
TFT - fluid temp
OSS - output shaft speed

2000 and earlier didn't have ISS or OSS(VSS was used)

On earlier 5Rs there was a sensor on top, by bellhousing end of transmission, but it was never used

Then the sensor I replaced must be the ISS. I have seen references to the ODS existing and not existing. If it is not there it certainly explains the odd readings. But in my scanner (OBD Link with their bluetooth hardware) I cannot find a PID for intermediate shaft speed. Only input shaft speed.
I have an ATSG manual for the 5r5e and it shows the ODS when did they remove it?

 

[tkmitchell]

Thanx for the replies. The symptoms is that it will not move. And throws no codes. Put it in gear and you can feel it engage. But just revs up. In R D 2 and 1.
It had been moving in 2 and 1, but that stopped also.
It is possible that during the rebuild something was done wrong. But no hard parts looked bad. Only problem as a couple burned clutches and the front bushing for the input shaft was loose and replaced. New rebuilt valve body with supposededly all new solenoids. New torque convertor.

At one point after rebuild was getting a code for the OSS, but I redid the ground cable on the battery and that doesn't show up anymore.

At a loss. I am going to get it to someone tomorrow who can do a AC ripple test on the alternator. A bad alternator has caused problems for others.

 

[RonD]

The sprag, one-way clutch, is bad, trans will often engage for a short while in 1st or 2nd but not D, but then 1st and 2nd goes away as well

Common automatic failure, not at all 5R55E or even Ford specific

Need a full rebuild, again, to get to the sprag

Yes, there would be no codes at this time because every thing is OK with sensors and solenoid, its a mechanical failure

It would be like taking your drive shaft out, there would never be a code, just no movement

The 5R55E will still operate with all sensors and the computer unplugged, will just shift harshly, there is nothing in the electrics that can prevent the transmission from being driveable
The sensors and solenoids were added to make automatics better in selecting a gear to use, and with better MPG than just using springs and balls and vacuum for shifting

 

[tkmitchell]

I was afraid of that. When we did the rebuild I thought everything was good. All the hard parts looked right and seemed to be working properly.
Well, time to drop it out again.
Thank you for your input.

 

[Orca]

What are the appropriate values for the Overdrive Drum Speed Sensor?
[...]
Right now, when it is idle input shaft speed is close to RPM. Output shaft speed is 0, what I expect because it is not moving. ODS show over 4000, not what I expected, or is it?

Because your post inspired curiosity, I looked into this a bit.

I have a 2004 Ford Ranger 4.0-liter V6 with 4WD which I believe has the 5R55E transmission. (Curiously, this would be contrary to the door jamb sticker, showing transmission code "D", and Ford's own 2004 "Owners Guide" which dictates that "D" = 5R44E.)

I set up a test using all known PIDs related to transmission shaft speeds then took a test drive.

I collected data on Turbine Shaft Speed (TSS), Input Shaft Speed (ISS), Overdrive Drum Speed (ODS), and Output Shaft Speed (OSS). (I'm not showing OSS in my attached image since it's irrelevant to this particular discussion.)

I'm reasonably confident of the PID decoding (formula) for TSS and ISS. I'm slightly less confident about the formula for ODS, simply because I'd never logged or plotted it before today, but I use the same formula (AB/4) as the TSS and ISS, so I suspect it's correct.

Furthermore, I have no idea if my transmission has an honest-to-goodness ODS sensor or if that PID's reply is somehow "synthesized" from some other data. I've found confusing and sometimes contradictory information about the sensors on the 5R55E.

Nevertheless, the graphs in the attached image show some things that might be useful to you:

First, ODS is zero (just like TSS and ISS, of course) before the engine is started (i.e. to the left of that vertical blue line labeled "engine start").

Second, once the engine is started (merely idling), ODS clearly jumps up (goes briefly off-scale, in fact) then settles down to about 3200 rpm (assuming my decoding formula is correct). So your live data showing 4000+ rpm is reasonably plausible.

The point in my ODS graph after that, where it quickly drops from 3200 to 0, is where I switched from (idling in) "Park" to "Reverse". There's a little "blip", going above zero RPM, where I back up a short way, then a spike as I go from "Reverse" to "Drive".

After that, ODS more-or-less follows both TSS and ISS up to the point where, unlike TSS and ISS, ODS drops sharply to zero RPM for a stretch near the right side of that graph. Presumably, this is where I'm in the highest gear.

Hope this info is somewhat useful. Good luck with your diagnosis!

 

[adsm08]

Hope your sprag didn't do too much damaged when it died.

I have seen a few transmissions demolished by a failed one way clutch.

 

[Dirtman]

Math is dumb.