Pls help, transmission problems

[robswe02]

Today I changed fluid and filter in automatic transmission, and after that, the engine stalls when I move the lever to drive(reverse works ok) and the service light comes on.
I overfilled the fluid first, most of the overflow came out through the vent and the rest was drained manually to the correct level.
Could something have been damaged from the overfill? Please help me with this, theres not many experts on American cars to ask here in sweden.

 

[Glacier991]

Wht this sort of sounds like to me is that for some reason when you put it into Drive, the torque convertor clutch is engaging at that time...I am having trouble imaging what else could kill the engine. [I guess a parking pawl that was not pulling out of the cog wheel could do that however that is a purely mechanical thing, and a fluid change should not affect that - and besides, you can use reverse]. How many miles on it? Explain how you changed your fluid? Just trying to get a clearer picture here.

 

[robswe02]

I removed the pan to drain the old fluid out, well it's impossible to remove it completly so I actually just placed it on top of the housing. Then I replaced the filter with new orings on and refitted the pan with a new gasket.
According to the manual the correct amount of fluid is 9.25 liters (don't ask me how much that is in gallons) so I started to refill, but after aprox. 5 liters it started to overflow. Then I did something stupid, I thought that if I start the engine maybe the level will decrease, and so it did, but only because the fluid was flowing out of the vent pipe. The level was still a bit to high so I drained out some more manualy (sucked it out trough the filling tube) untill the correct level was obtained,restarted the engine and found that the trans is no longer working properly.
The Explorer is a -97 4x4 4.0 SOHC with 87500 miles.

 

[Blee1099]

You overfilled it.. The fluid amount is with the torque convertor. Since you only did a pan drop, your using less than 1/2 the fluid listed on the owner's guide. Try draining the fluid & refilling it to the proper amount.. You should only need about 4 1/2 quarts to refill it.. I would start with 4 and slowly check it with the engine running and run it thru all the gears after changing the fluid. Then put it in park and check the fluid.

 

[robswe02]

Thanks

Thanks for your quick reply, I will try this first thing tomorrow morning.
So you mean that there was about 4 liters of the old fluid still in the converter, how do I drain that out? I did this fluid change by the Haynes repair manual, and there were nothing about the torque converter. I thougt I lost the last amount on the ground outside the bucket. If I drain the pan again will the level in the converter still be to high? I ask because when I sucked out fluid trough the filling pipe the level ended just at the very top of the dipstick but the problem was still the same.

 

[Glacier991]

I'm still puzzling this one. ALmost like a hydrolock. Two opposing things activating in Drive... or the TC (I am still vaguely skeptical on that even though I suggested it, mainly because I cannot fathom how that could happen on a simple overfill). I guess a complete drain is, as Blee suggested, a place to start....still Quite curious. I will be anxious to know what you find out....add to the knowledge base.

( I have to tell you though... the TC clutch is yet looming large as the culprit in my mind... the things there that matter here are the TCC solenoid and the Torque convertor clutch shuttle valve (and it's spring) located in the valve body. I am at a complete loss to explain why an overfill would affect any of those.)

 

[general x]

Its bad for your tranny to be overfilled correct? What exactly happens to a tranny when it is run when it is overfilled? does it blow out seals?

 

[robswe02]

Maybe internaly, but I got no external leaks after the "incident"

 

[Glacier991]

An overfill condition does not, as is commonly believed, lead to blown out seals. That's an old myth.

 

[robswe02]

I followed the advice to drain and refill the fluid to correct level, but it's still the same problem. Reverse works ok but drive kills the engine, I even tryed to give some more throttle when I moved to D, but the car just jumped 3 feet forward and stalled.
A thought came up, there are some electrical connectors(switches?) inside the tran case, you see them when the pan is removed, anybody who knows what they are for? Maybe I accedentely disconnected one of those when I tryed to remove the pan! Could that be something?

 

[Glacier991]

That could possibly do it. They are for the solenoids and sensors.

 

[liqhx2]

sounds like TCC to me

 

[Brain]

Yes, it sound like the torque converter clutch isn't disengaging, which causes the motor to bog down and die (like trying to start a car with a manual transmission in first gear with the clutch out).

There are three modes that the torque converter clutch (TCC) can be in:
1) unlocked (disengaged and slipping - which is what you need)
2) locked
3) electronically inhibited (unlocked by means of computer controlled solenoid)

If the solenoid is malfuntioning (shorted for example), it will usually go to it's normal position, and in this case it is normally open which causes the the TCC to be unlocked. To get TCC lockup to occur, there has to be 12 volts applied to the solenoid valve to keep it closed. The ports on this valve are pretty small, but I don't think that this is the problem.

I was trying to think what could cause this to occur, and I came up with three things that are most likely the cause (assuming that it was working properly before the fluid and filter change).
1) converter clutch shift valve is stuck
2) converter clutch shuttle valve is stuck
3) possibly but not as likely the shuttle ball between #1 and #2 is stuck

Any one of the three requires dropping the pan and removing the valve body. You could eliminate all three of these potential issues at the same time. Changing the fluid could have let some debris settle where it wasn't before, causing a stuck valve or ball (which is smaller than a pea). It wouldn't take very much to get a stuck valve. Do you need pictures of the right part of the valve body to look at?

I'm still a little bit confused why you would be able to have reverse work OK and not drive, but I'll think about that some more.

Also, for future reference, you can remove part (if you ever overfill it again) of the fluid by disconnecting a cooler line near the radiator (rubber hoses connected to the auxilary cooler right behind the grill up front).

There is no way to drain the torque converter, as there is no drain plug...the best you can do is a "flush" as has been described in this forum before (drain pan and replace fluid in pan, remove cooler return line and add fluid as it is pumped out).

 

[robswe02]

Thanks to all of you for your engagement in this, and to "Brain", yes pictures would be very helpfull, this looks a bit to complicated for me to handle myself.

 

[Brain]

I just so happen to have a 5R55E valve body out and handy, but I'll have to wait until I get the camera back. So does the motor almost die when shifted into reverse? Also, do you have a multimeter to test electrical connections?

 

[robswe02]

When I shift to reverse the RPM drops to about 300 for a second, then up to 500 and stays there steady. I got a multimeter here at work that I can use, if you instruct me on what to check.

 

[Brain]

OK, I might need a bit of time to complete this, but here's a beginning anyways.

First remove the pan and filter. Then remove the reverse servo cover and servo (looking at the bottom with the front at the left side):

Then remove the electrical connectors from the six soleniod valves (they just push on/pull off):

Here's a picture of four of the six connectors without the solenoids attached:

Then remove the rest of the bolts that are showing and gently remove the valve body from the case. The shift selector has a pin that goes into the manual valve. Take a second to look at it before you remove it.

This pin fits in this slot in the manual valve (also shown on the other pictures of the valve body):

The locations marked A and B are the two spots ("bore") that could be causing the problems if parts are sticking inside. "A" is the bore with the TCC solenoid and the shuttle valve and spring. "B" is the bore with the TCC shift ("modulator") valve and spring. The shuttle ball isn't visible from this photo.

More later.

 

[robswe02]

Is it possible to replace one of the solenoids without removing the valve body from the case? I think I might have damaged the one you marked with "A" when I removed the pan. I will open up again today after work and take a closer look at the solenoids, but this time, remove the driveshaft first!

 

[Brain]

Before you drop the pan again, let me post a bit more about testing the solenoids and give you some better pictures.

 

[robswe02]

I have removed and tested the TCC solenoid ("A") and it seems to be working properly.
No power, open flow and 12V connected, closed flow. The damage that I suspected was nothing, only the connection pins that was a bit bent. However, I will remove and test solenoid "B" later today.