possible 4WD issues

[TheScotch]

I've tried scouring forums for issues like mine, but I can't seem to find the exact one. I just bought this truck last week, here are some specs:

2000 Ford Explorer Sport 4.0L SOHC
190,000 kms
unknown service history

So I have the blinking six times in-dash and it happens at random times, always on startup though and more often on the hwy.

I did a little test and moved it to 4LO in neutral and drove in circles in a parking lot, didn't really notice anything change and it was smooth, not exactly sure if 4LO engaged since it didn't light up in-dash. I also did a few circles in reverse.

Put it back in neutral and switch it to 4HI, here it was very rough, just didn't drive smooth at all in D or Reverse. Also, nothing lit up in-dash apart from the blinking six times.

I then put it back in neutral and returned to AUTO and it was driving normal, but again, didn't 'feel' anything switch, but it wasn't a rough ride.

I've read that it COULD be one or more of the following:
- HALL sensor
- Transfer Case Speed Sensor
- bad GEM
- faulty TOD
- (please say it ain't so...) bad transfer case

I have an appointment at my mechanic in a few days to address a few other very small issues, but he's not a transmission specialist, so not sure he'll diagnose the issue. Anyone able to pinpoint something from these few details or recommend methods I might be able to drill down the issue with?

 

[Bill MacLeod]

Remove the negative battery cable for 20 minutes. This will reset the computer. Sometimes this is all that is needed.
Since you just bought the truck, this is a good time to change the transfer case fluid.
I had the same issue with my 99 last winter. Computer reset didn't help me so I was ready to order new speed sensors. Decided to change the fluid with Mobile 1 synthetic Mercon V. No more flashing lights, 4x4 hi & low now function properly.

 

[TheScotch]

Remove the negative battery cable for 20 minutes. This will reset the computer. Sometimes this is all that is needed.
Since you just bought the truck, this is a good time to change the transfer case fluid.
I had the same issue with my 99 last winter. Computer reset didn't help me so I was ready to order new speed sensors. Decided to change the fluid with Mobile 1 synthetic Mercon V. No more flashing lights, 4x4 hi & low now function properly.

thanks for the tips Bill. Did you do a flush or just simple change of the fluid?

 

[Bill MacLeod]

Remove top plug (fill plug) first. Some times this plug can be seized so remove before draining.
Remove lower plug to drain. Takes approx 1.75 ltrs.

 

[TheScotch]

haven't tried either of Bill's options yet, but anyone else have insights with similar issues you've experienced?