O/D off light flashing / weird shifting - 98 auto Ford Explorer Eddie bauer

[sinfall]

So, we just got 36 inches of snow here and it was time to dig out the explorer. I put it in 4wd low and drove out of the snow.

The next day the wife went out and took the explorer, when she got a couple miles down the road she noticed the O/D off lights flashing and the truck driving sluggish, shifting weird and high rpms.

I've noticed a few different answers to this

1. speed sensor
2. Tranny valve body
3. 4wd low engaged and stuck

The tranny was rebuilt about 20k miles ago and of course had a 12k mile warranty.

I was hoping to replace teh explorer sooner than later, but if I have to dump a lot of money into it, I may not be able to.

Any suggestions?

 

[scucci]

I had that problem a couple of months ago when we had a snow/ice storm. Probably stuck in low range. I had my son get under the expy and listen to the shift motor while I shifted from low to high and back. The motor was very sluggish and didn't have the guts to pull it out of low. He tapped lightly on the motor and it went to high range and no more flashing OD lamp.
I pulled the shift motor, cleaned up the commutator and brushes and cleaned and lubed the gears and freed up the almost impossible to turn encoder(crc silicone spray lube on the shaft) and it works great now.

Auto and High only engage the clutch, they don't shift anything inside the case. They are purely electrical. Auto sends a pwm current to the clutch to cause partial clutch engagement. Two speed sensors in the case sense the difference in shaft speeds to apply more lock up to the clutch when needed. High sends a 100% pwm to the clutch to lock it on full time. The shift motor has one function - to shift into and out of low range.
The motor end encoder is similar to the early style, but you can't get to the sealed encoder contacts. The removal is similar to the 96 motor, except you need to remove the two magnetic sensors from the case - 1 bolt each. The brown wire must be removed. Pull the red lock out and then use a jewelers screwdriver to gently move the plastic hook while pulling the wire. Scribe witness marks on all removable parts, including the encoder cover held on by torx screws. It has slots for adjustment and you don't want to get it back on out of adjustment.

To check for this the trans must be in neutral, foot on the brake to shift into/out of low range. With key on, engine off brake on, trans in neutral shift into high or auto and have a friend get under and listen for the shift motor. If not working lightly tap on the motor and see if it shifts. You can also remove the shift motor and manually shift to high range. Could be the 4x4 switch, shift relay module, shift motor, GEM or transfer case that has a problem. Look in the sticky section for shift motor rebuild and 4405 t-case rebuild. You could also pull the shift motor and manually move it to high range. Your shift motor is slightly different than the 96 model shown in the following links.

Could also be the trans - visit the trans-diff-transfer case forum and post a question there. Lots of knowledgeable guys there.

 

[Axial32]

Did you make sure to put it in "N" before shifting out of LO... if you just shut it off and didn't shift it out it says in... and even while I'm mudding or playing in the snow in LO it'll flash letting me know I'm still in it... even once you shift it out while everything's blinking you'll still have to shut it off to get the overdrive light to go out.... at least it worked for me....

 

[FloridaState]

Far from snow here in Florida, but I was on a long road trip about a year or so ago and I had the OD light start flashing. It was running very high RPM's only going like 70mph --the RPMs were above 3500 if I remember correctly (usually 80mph the RPMs on mine are about 28-2900). I ended up needing a new torque converter and tranny rebuild.

I don't know if this is the same thing or not...but I did have the flashing light problem. I don't know if I actually NEEDED a tranny rebuild (pretty dumb with engines/transmissions), but we have a friend who does it, so my dad figured we might as well just get it rebuilt while he's messing with it.

Haven't had any problems since (knock on wood).

 

[FloridaState]

Oh and I think we also got a shift kit installed. Not sure though.

Dad dealt with all that stuff, I just wanted my truck back. lol

 

[Paraphoe]

You should be able to tell if it's in 4wd, especially low, by the binding in turns.

 

[marragtop]

When the OD light is blinking, the trans goes into 'limp' mode which results in hard shifting. Reset the codes by disconnecting the battery for 5 minutes. If the blinking light re-occurrs you should get the trans codes pulled to see what they are. My 95 OD light starts blinking about once a year. When this happens, I reset the codes and I'm good to go.

 

[Flick75]

i have a 2001 sport. What codes are you talking about and how do you reset them?

 

[marragtop]

I'm referring to the OBDII codes. You can reset them by disconnecting the battery for 10 minutes.

 

[Flick75]

Thanks for the reply.