96 Explorer Transmission Blues

[greasemanicure]

Daughter drives a 96 Explorer, 4WD, 4.0 6Cyl that started to show some transmission symptoms.
1) First symptom was a bit of a shudder going into reverse.
2) This tended to happen when warm rather than when cold.
3) As we have had this truck for about a year with little knowledge of maintenance, dropped the pan, changed filter and fluid. Fluid was a bit dark and smelled burnt. Fines on the magnet and nothing else in the pan or fluid. Did this about 3 weeks ago.
4) Last week shifts to overdrive started to be sloppy with hi revs. Reverse got slower going in and would sometimes slam in at about 2k revs.
5) Last night reverse shuddered its last and quit. OD light flashing sometimes as well.
6) Pulled the codes with a P0761 "Shift Solenoid C CKT Performance or Stuck off". OD seems to kick in going downhill. Seems to be no engine braking.
7) Fluid is at the full mark, clear red with some residual "sootiness" from the partial change with the pan drop 3 weeks ago. No smell to speak of.

I might be tempted to do some or all of the work myself (more adventuresome these last few years). What further might I be able to do to diagnose and identify the problem(s)? Can I get over equating AT work with brain surgery?

 

[BrooklynBay]

How many miles are on it? So now you have no reverse, and overdrive only going down a hill. How do your other gears feel? Do you have a problem with low (1st) gear? Are all of your gears very sluggish without a positive engagement? What kind of shavings were on the magnet? Were they mostly metal, or a mixture of band, and clutch material?

 

[greasemanicure]

No problem with first or the other gears. Maybe a hint of sluggishness into first, but the others feel solid. What I found on the magnet seemed to be very fine metal. I mean VERY fine. It was all uniformly "silver" in color and the consistency of very fine filings from hard metal, with no remarkable variation in particle size. I filtered the pan fluid for non-ferrous material and did not find anything other than "soot" on the filter paper.
Is it worth dropping the pan again to see what I find since reverse went dead?

 

[greasemanicure]

One thing I forgot ..... there are about 160K on the odometer.

 

[BrooklynBay]

You might have to rebuild the valve body. First check the DTR sensor. Do you have your back up lights working when you put it into reverse? Do you have a 0-300 PSI pressure gauge? Connect this gauge, and test your pressure in all gear settings. You might just have a blown gasket. Since you have 160k miles, you most likely have a bad EPC solenoid, and would have low pressure in all gears.

 

[NHale623]

Here's a link to a thread where the use of a pressure gauge to diagnose transmissions is discussed:

http://www.explorerforum.com/forums/showthread.php?t=117998

 

[greasemanicure]

I really appreciate all the benefit of your experiences. Thanks!
I do have backup lights in reverse. I believe I can beg or borrow a gauge, and from the helpful link from NHale623 to Glacier991's post, it looks like I'll need to mate with a 1/8 NPT on the tranny. Is it likely to be the same on the 4R? Also, where on the 4R body should I look for the pressure port?

 

[Glacier991]

Well, let me start by suggesting that at 160K your transmission has given you a good life, no matter what.

Let's address your code first. Your code identifies the SS3 (or SSC) solenoid as having failed either electrically or mechanically. It has probably failed in the off position - likely an electrical failure. You will lose 4th gear with this failure. So replacing that solenoid will likely get you 4th gear back.

Now lack of reverse and other issues. At 160K I can almost guraantee that your EPC solenoid is a tired puppy, and replacement will likely improve your pressures. Will that get you reverse back ? I dunno.

Also the separator plate gaskets had a tendency to blow out in these trannies. Causing loss of various gears. The DTR sensor on the case "could" cause this, but I think it a low probability.

So, you can rebuild the VB, along the lines shown in the VB rebuild Diary, and it MIGHT assist you.... but at 160K there is also a not inconsiderable chance that your lack of reverse might be related to a burned up reverse clutch, or similar mechanical issue inside the tranny - which is rebuild time.

So, you can do the VB rebuild with an excellent chance of fixing the lack of OD and maybe a 50/50 chance of fixing reverse... cost around $200 to $300. If it does not work, you will be that far ahead on a rebuild, where VB's tend not to get the care they deserve. If a complete rebuild would make you junk the vehicle, you might not want to invest the time and $$ with no guarantees.

 

[greasemanicure]

Here is the picture I have in my mind.
A VB rebuild is likley to bring back 4th gear and improved performance in the other forward gears.
Pressure measurement results might raise or lower the probability of reverse coming back, but still not
Given that the rest of the Explorer is in better shape than mileage alone would suggest, a rebuild is not out of the question.
A rebuild is in the short run and maybe the long run a better risk than replacement with a used vehicle of dubious background.
From reading on this site, the VB kits and other necessary / recommended parts are good and uniform quality for a home rebuilder, and the diaries can help fill in the blanks.
If the VB does nothing for reverse, I still can or must send it out for the rest of the rebuild.
Aside from an opportunity to get dirty, are there any downsides I should be considering?
Thanks again!

 

[Glacier991]

I think you are on the right track then. I'd flush the tranny before I dropped the VB to rebuild it.

It occurs to me a plugged filter COULD cause your loss of reverse.....anyway... keep us posted.

 

[greasemanicure]

I was aware of plugged filters causing that kind of problem. Had that happen on a Jeep Grand. Coasted to a stop. Shut down, check things out. Start up and take off for a few trouble free miles and coast to a stop again.
Changed the fluid and filter earlier when the shuddering started with no improvement. There was little visual difference between the old and new flter.
Unless there is a 4R VB diary that I have missed, I will review the 5R VB diary and give it a go. I'll let you know how it goes.

 

[BrooklynBay]

The 5R valve body could be used in the 4R transmission.

 

[Glacier991]

Use the 5R55E VB Diary to rebuild the 4R VB you have.

 

[greasemanicure]

It has been a while since I got all the advice and encouragement abour rebuilding the valve body on the 96 Ex. I did not get "a round tuit" until recently and finished it yesterday (1/27). The forward gears came back but reverse did not. Banking on this possibility, I have been searching for replacement trannies and can get a deal on one. The only hitch is making sure that it is RIGHT. The one I rebuilt the valve body on has the number P97GT-7006-BAR. One that I can get is P97GT-7006 BBR. Are they equivalent? From the picture and all the bolt holes they are a match. Any thoughts? I don't want to go through a pull and replace (with my rebuilt valve body put in the replacement), only to find out that the one letter difference is a death dealing blow. Any thoughts?

 

[BrooklynBay]

I don't know what the last digits represent in the production #, but it sounds like the second one (B) is newer than (A) your original one.

 

[greasemanicure]

Thanks for the quick response that you are known for. I had a chance to see the transmission and there are two differences not evident from the pictures. There are two two-wire electrical connectors on top of the BBR transmission that are not on top of the BAR transmission. One is near the input shaft and the other is near the output shaft. I went pin by pin through all the electrical diagrams I could find for 95 through 97 Explorers with 4.0 engines and could not find any differences in the PCM to transmission connections. Does this shed any additional light on the subject?

 

[Glacier991]

Those sound more like case ID's. Your tranny ID is on a tag. Like XL2P-DA-2, on the bottom line of that tag is the build date.

They did add sesnors to the 5R55E along the way... if your new one has MORE you are ok, less, no.

Your lack of reverse sounds more like a bad reverse clutch situation....or other bad internal problem....

 

[greasemanicure]

Spending some time in your Frankentranny sticky post, I am nearly convinced that the one I can get is a 5R. It does have more sensors than the original and the markings on the servos match what your pictures show for a 5R. The final question is: If what I pulled out is a 4R and what I have to replace it is a 5R, is the vehicle and the PCM going to be happy with it? It sounds like I would have a better end product, but I don't have the experience to say that with any degree of confidence. All the other electrical connectors appear to be a match, as do the measurements on the TC.

 

[Bent Bolt]

I have looked into that before and concluded that yes, a 5R55E will work just fine in place of a 4R44E. The bulkhead connectors are indentical and all terminals serve the same function in both trannys. As long as the bellhousing is the same you're good to go.

Keep in mind that you will still have a 4 speed trans as the 5th gear is actually a PCM calibration rather than an internal difference in the trans.

And before anyone asks, no you cannot recalibrate a PCM to command 5th when it only has 4 gears.

 

[BrooklynBay]

What about swapping a PCM, and wiring harness?