O/D Flashing Woes

[bluelagoon]

I have a '97 Explorer XL 4X4 4.0L OHV, and I believe a 5R55 transmission. Driving is fine except half of the time when I am approaching 110km/hr the O/D light begins to flash, the RPM reading on the dash won't drop down to 2500, instead it stays up at 3000. And when I begin to slow down the shifting is horrible, and it is a bit harder to brake. eventually the light turns off on it's own, but then comes back on regularly. I had it looked at by a trasmission guy and had the transfer case replaced but I still have this problem?

 

[OVERKILL]

Just some more info guys (this is my little sister, who lives over 1500km away from me, this is my old Explorer). The transfer case problem is separate from the O/D issue. I was having the O/D issue when the truck was mine and I replaced the TPS and it made it happen less frequently, but it still did it. Then, eventually, the transfer case started to go out of it (bad grinding when trying to go into reverse, tranny would go into gear, but the T-case wouldn't) but it happened VERY rarely.

My dad ended up buying the Explorer back from me (I bought a Mustang) and sent the truck to the tranny shop. The guy had the vehicle for over a month, replaced the transfer case and a "sensor" on the transmission. What he replaced exactly was pretty vague, and I was hearing about this over the phone from my dad who was trying to describe what he was told as best as he could. Well, the problem persisted and the tranny guy kept stating that this "plug" kept getting un-plugged so he ended up putting some GLUE on it!!! Anyways, after that, the problem was still there and my father has refused to take it back. This was several years ago.

She has been driving the Explorer like this for a number of years now, the transmission is in limp mode, but when it first started doing it for me (in like 2002) the shifts were so hard they hurt your neck. Its not like that anymore, its still definitely shifting hard, but no where near THAT card, so I'm wondering how much damage/wear has been done by it being driven in limp mode for so long? The truck has pretty high mileage on it now (close to 300,000Km, though I'm sure BlueLagoon can fill us in on the exact figure) but its her daily driver and its my feeling that it really should be fixed. I didn't have the money to fix it at the time, Ford told me it was a seal? and dad's attempt at getting it fixed seem to have been in vain.

Any input would be appreciated.

 

[Glacier991]

What would be helpful is to know what transmission code is being set. The first post clearly indicated it was giong into FMEM or "limp" mode. The rpms says you do not have OD. Often these types of problems can be a sensor input issue, although high mileage 5R55E's often have EPC issues. I am on the verge of a blanket recommendation that you replace your EPC at 125,000 miles regardless.

Your RPM's are consistent with a lack of OD. Again, sensor inputs (like VSS just as an example) can often figure in here.

As for FMEM shifts... I am not sure if over time they would cause any damage. I would think the greatest damage, if any, would be at anchor pin locations in the case, and or broken bands. Both would be evident.

 

[BrooklynBay]

Maybe the FMEM mode wore out part of the bands, and it might need an adjustment after the EPC is replaced?

 

[OVERKILL]

I don't think we are getting any readable codes, and pardon my ignorance but what is the EPC?

 

[Glacier991]

If you are flashing an OD light your computer is setting a code. EPC is the electronic pressure control solenoid. You might enjoy reading the 5R55E Valve body rebuid diary in the sticky threads at the top... it explains all that jargony stuff.

 

[NoMoFords]

Flashing O/D Light Again?

Posted here last month and got great info on Tranny rebuilding. Decided I didnt have time to Do it myself so I took it to the shop and had them put in a Jasper Tranny I liked the warranty 3years 100,000 miles. Tranny shifts fine only problem now is every 2 or 3 days the O/D starts flashing. I have taken it to the shop but only after restarting the truck in which it reset the O/D. Any advice or ideas of what the problem may be? Also service engine light came on checked the code Oxygen Sensor has gone bad or possibly damage during the tranny install.

 

[OVERKILL]

This issue was resolved with a new valve body assembly and torque converter. Truck has been great for over a year now.