5r55e Problem Saga (merged thread) PROBLEM SOLVED !

[bustdnukls]

Recently purchased a '99 XLT, 4LSOHC with 206,000 miles on it to restore for my son. I'll go into the multitude of problems and repairs in a separate post, but the one remaining issue is the overdrive or lack thereof. The symptom is the O/D off light sporadically coming on and flashing. I printed the 5r55e chapter of the Mitchell Manual and the pertinent postings here. I removed the pan and tested all the shift solenoids as well as the EPC & TCC solenoid resistances and all were in spec. I removed all of these and bench checked to make sure that they changed state when energized. I cleaned and reinstalled them and checked resistance again through the 16 pin connector. I found the output shaft speed sensor to be under spec on resistance (295 ohms), so I replaced it, assuming I was getting a faulty speed signal. Installed a new filter and Mercon V fluid. Now the transmission shifts smoothly up through 4th and maybe 5th, but the light will still start flashing sometimes as I come to a stop or other times on accceleration. You've guessed by now that I don't own a professional grade OBD2 scanner & I'm cheap! I suspect that the EPC solenoid needs to be replaced. Should I break down and buy a good scanner (what kind?), pay the local shop to read the codes when the light is flashing (it resets with quick restart of the motor), or try the new EPC and/or shift kit? One last point, I just completed a 300 mile trip and at 70 mph the engine is turning 3000 rpm. Turning off the O/D only increases the rpms to about 3100 and fuel mileage was only 15.2 mpg.

 

[97greenmonster]

http://www.explorerforum.com/forums/showthread.php?t=175065

There needing test beds for that solenoid on the 5R55E. Go check it out.

 

[DR98]

For a scanner pick one from this web site http://www.actron.com/product_category.php?id=249

Actron OBD II Autoscanner runs around $100.00 at Auto Zone.

Dean

 

[bustdnukls]

thanx for the link.

 

[bustdnukls]

I've done a lot of research on scanners and I'm leaning toward a PC tool, but want to make sure it has the capability to read the manufacturer specific codes for the transmission. I was favoring the Actron 9145 model in the handheld versions. Thanks for the response.

 

[dogfriend]

One last point, I just completed a 300 mile trip and at 70 mph the engine is turning 3000 rpm. Turning off the O/D only increases the rpms to about 3100 and fuel mileage was only 15.2 mpg.

Sounds like your TCC and/or OD may not be working. 3100 sounds about right for 4th gear @70 mph. 5th gear is approx 2500 rpm @ 70 mph on my truck (4.10 rear axle, 255/70R16 tires).

My truck shifts into 5th at approx 42mph on flat ground with a light foot on the throttle, so you might want to see if that works for you.

You really need to get the codes. Be careful to get a scanner which reads Ford Enhanced codes. A PC based one might be the cheapest option.

 

[Allbert]

Sounds like your TCC and/or OD may not be working. 3100 sounds about right for 4th gear @70 mph. 5th gear is approx 2500 rpm @ 70 mph on my truck (4.10 rear axle, 255/70R16 tires).

My truck shifts into 5th at approx 42mph on flat ground with a light foot on the throttle, so you might want to see if that works for you.

You really need to get the codes. Be careful to get a scanner which reads Ford Enhanced codes. A PC based one might be the cheapest option.

Agree that it sounds like TCC may not be working... the PC based scanner I bought for use at work can be ordered at www.OBD-2.com . You can get an adapter for just one protocol (like Ford PWM) for around $125 or adapters that support multiple protocols for more. The software (downloadable) supports real-time monitoring of enhanced OBDII data, which for Ford trucks with 5R55E transmissions includes things like TCC duty cycle, turbine shaft speed, output shaft speed, etc., so you can actually tell how much slippage there is in the torque converter to see if the clutch is working like it should or not.

 

[bustdnukls]

Agree that it sounds like TCC may not be working... the PC based scanner I bought for use at work can be ordered at www.OBD-2.com . You can get an adapter for just one protocol (like Ford PWM) for around $125 or adapters that support multiple protocols for more. The software (downloadable) supports real-time monitoring of enhanced OBDII data, which for Ford trucks with 5R55E transmissions includes things like TCC duty cycle, turbine shaft speed, output shaft speed, etc., so you can actually tell how much slippage there is in the torque converter to see if the clutch is working like it should or not.

Albert & Dogfiend, Thanks for the input. The Service Engine light came on after my first problem posting. I bought a scan tool and retrieved code P1715 (SS2 Solenoid Failure). The light went off after clearing this code and I no longer get the flashing OD light. Now the only issue is that it won't stay locked in OD. It shifts into OD under load at about 65 mph and the rpms drop to about 2500 momentarily, then it kicks out. Would a bad TCC cause this? Would low line pressure (EPC) cause this?

 

[dogfriend]

Can you hook up your scan tool to read PID(s) (parameter ID) while your truck is trying to shift into 5th? I know that there is a PID for commanded gear (i.e. what the computer is telling the solenoids) and for TCC duty cycle.

Also, do you have a copy of the Ford Service Manual? If not, you can try to find one on Ebay (CD) or download one here. In the service manual, they have a section with Diagnosis and Testing procedures for the 5R55E. Its way too long to post here.

I have the 97 manual. Under the symptoms list they have: "Torque Converter Clutch Operation Concerns: No Clutch Apply"

They split the troubleshooting into two routines; electrical and hydraulic/mechanical.

For Electrical, run Pinpoint Tests A & F

Pinpoint Test A shows the chart of which solenoids should be on depending upon the commanded gear (from the PCM). They also have charts to show what happens when solenoids get stuck on (or off). It is interesting in your case that when SS2 is stuck on (and the lever is in OD) the chart says you will be in either gear 3 or 4 (1:1) regardless of the commanded gear by the PCM.

Pinpoint Test F is a routine to test the TSS and OSS sensors.

For Hydraulic/Mechanical, they want you to check for:

Main Control Assy (valve body)

Screw out of torque spec (I'm assuming they mean the bolts holding the valve body)

Gasket damaged

Separator plate damaged

Converter clutch control valve, thermostat bypass valve/cooler limit valve spring damaged, missing, misassembled, stuck, bore damaged

TCC solenoid and valve stuck, damaged etc.

Pump Assembly

Front pump seal worn or damaged

Screws out of torque specification

Torque Converter Clutch Assembly

Torque Converter internal malfunction preventing lockup


I would check the electrical first using the Scan tool, then look into the valve body/ solenoids because you can do that without removing the trans from the truck. If its the pump or the TC, then you will need to remove the tranny.

 

[Allbert]

Albert & Dogfiend, Thanks for the input. The Service Engine light came on after my first problem posting. I bought a scan tool and retrieved code P1715 (SS2 Solenoid Failure). The light went off after clearing this code and I no longer get the flashing OD light. Now the only issue is that it won't stay locked in OD. It shifts into OD under load at about 65 mph and the rpms drop to about 2500 momentarily, then it kicks out. Would a bad TCC cause this? Would low line pressure (EPC) cause this?

With the PCM reporting a code 1715, mechanical failure of SSB, the Ford CD I downloaded says go to pinpoint test F which says to replace the indicated solenoid and re-test. Although I've never been led to a transmission issue by a DTC before, all the other components I've ever been led to by DTCs (like EGR valves, and MAP sensors and such) have either been bad themselves or have had bad connections, so I guess I'd check everything about the SSB.

Does anybody else have experience with this fault that would suggest other action?

 

[bustdnukls]

Quick update: I can't read the PIDs with my ELM327 and haven't found any software that can. I've ordered a pressure gauge to check line and control pressures. In the meantime, I wired a pilot light in parallel with the TCC. The TCC is energized at 44 mph and stays on until the throttle is released (as it should) so it appears that the right input is provided to the TCC. If the pressures are ok, I plan to remove the valve body, clean/inspect, retest the TCC and EPC and install a B&M drain plug. Question is, would low line and/or control pressure (bad EPC) prevent the TCC from functioning properly?

 

[dogfriend]

Question is, would low line and/or control pressure (bad EPC) prevent the TCC from functioning properly?

I think that is possible. The list I posted above lists several conditions which would lead to low line pressure - leaks in the valve body gasket or leaks in the pump seal. Testing the line pressure sounds like a good next step.

 

[Bigg_billy]

Hit this guy up in the tranny section, Glacier991. He's a pro at those trannies.

Bill

 

[bustdnukls]

5r55e Problem Saga (merged thread)

Glacier991,

Please refer to my original posting (in the wrong forum!) for the recent history and symptoms relative to no overdrive on my '99 xlt 2wd . http://www.explorerforum.com/forums/showthread.php?t=175602.

OK, I wired a pilot light to the TCC feed and it's getting the modulated input signal at the appropriate speeds/throttle positions.

Today I received the pressure gauge I ordered & I ran the line and EPC pressure tests with the following results:

Line Pressure.......Idle (Spec)........ Stall
P&N ..................85 psi (75-120) ....na
R ......................65 (175-215) .......na
D, 2, 1 ...............70 (100-135) ......225 psi (228-263)

EPC Pressure .......Idle (Spec) ........Stall
P&N ...................25 psi (22-40) .....na
R .......................53 (55-65) .........na
D, 2, 1 ................40 (40-50) ........115 psi (112-134)

Would low EPC pressure yield the low line pressures or do I have it reversed? Mitchell Manual seems to point toward valve body/separator plate issues. I plan to remove, clean, inspect valve body and front band servo next.

I would appreciate any suggestions as to the real root cause!

 

[Glacier991]

I read this thread and moved it to the Tranny section where I merged it. Damn. When you have DogFriend and Allbert in your corner, my input is virtually unnecessary. Trust me the advice here is top drawer by folks that ... especially combined, are equivalent to design engineer status PLUS. You cannot find this anywhere else, trust me.

My meager thoughts to add: So much can be wrong in the 5R55 VB that for a baseline, I would consider replacing the EPC and also the SSB, as a starting point (because it is easy... be sure and check the Solenoid bracket for integrity at the same time. (Bath number 1))

Should that not fix it, I'd drop the VB, fully expecting a bad gasket somewhere, and absent that rebuild it along the lines of the 5R55E VB Rebuild Diary (bath number 2).

If your fluid has not been refreshed in a while, (I do not think this is a fluid problem) you might want to flush is before "bath" step number 2 and drive it a week or two before doing that. Remember Merc V is golden in this tranny. I am at the point that even if you add a full syn instead of Merc V then add a friction modifier from Lubegard.

Bigg Billy... thank you for the vote of confidence.... but more and more this board is building a cadre of really strong tranny experts. Dogfriend is one of the best EEC-V hands on this board....Bent Bolt (he will post here eventually) is an actual FORD tech and a good one, and Allbert.... well Allbert is a design engineer type on this stuff. I'll say it again - you cannot buy this kind of advice anywhere.

NOTE: This post was a merged post, my next post answers your post above.

 

[Glacier991]

No you have it right. Your EPC pressures are in the ballpark.... your line is WAY low.

Low line... geeze so many possibles.... stuck checkball in a drum, bad pump, leaky pump seal, etc....or a blown out VB gasket.

Of these ONE is a simple check and replace.... the gasket and these trannies are notorious for those.

I'd do the FORD TSB (set forth verbatim in the first page of the 5R55E VB Rebuild Diary) and see how that affects things, IF you find a blown VB gasket on disassembly, you KNOW you have found the problem.

So often one thing can look like other problems in these transmissions. lets work our way UP the ladder.

And, when someone actually gives me pressures (EPC and LINE) and has bought a pressure gauge to help diagnose the problem, I will work with you til the cows come home to solve your problem, THANK YOU for being active in your fix!!

I hope your bath is but once.

 

[BrooklynBay]

I have a tool for sucking out ATF through the dipstick filler pipe. That is good for getting out a lot of fluid before you drop the pan. After the pan is off, it is a good idea to install a drain plug.

 

[Bigg_billy]

And if you put a tranny pan drain in while you have it apart, it might help Bath 1 become Sprinkle 1 next time around.

Bill

 

[BrooklynBay]

Check this post for more options on removing the fluid without taking a bath.

 

[dogfriend]

Check this post for more options on removing the fluid without taking a bath.

I tried to suck fluid out of the dipstick tube when I changed my fluid. I didn't work. I think the problem is that the top of the filter blocks the hose from reaching the bottom of the pan.

The best hint that I saw on this was (I think) from Fortune410. Get a large flat tupperware (or equiv) storage container, the type that is designed for storing items under a bed. The one I have is about 18" wide x 36" long. Works great for catching all (most) of the fluid.