Hi, We purchased this 1998 Expedition with the 4.6 in late March 2005 with 138k miles. There have been no problems until last week when I switched from 2WD to AWD and then to 4WH and then to 4WL. It went into AWD but not into 4WH or 4WL. I took it to our mechanic of 15 years and he had one of his employees replace the two speed sensors. However, now the AWD light on the dash stays lit solid where it used to flash. When switching from AWD to 4WH, nothing happens and the AWD light on the dash stays lit. When switching from 4WH to 4WL, nothing happens and the AWD light stays lit. When switched back to 2WD, the AWD light goes out.

I also had him drain and refill the transfer case with fresh oil since replacing the speed sensors would cause a small amount of fluid to be drained. The questions I have are:

1) Should the AWD dash light flash or be solid? My mechanic left yesterday to go hunting for a week and the guy now in charge says he called today a local Ford dealership and was told the AWD light should be solid, and if it was flashing before then there was a problem before. If that is the case, then at least the speed sensors fixed that unknown problem because now the AWD light is solid. So, flashing or solid AWD light...which is correct?

2) Why would the AWD light stay lit and the 4WH and 4WL lights not come on when the switch is turned to the appropriate spot, and why would the 4W not engage with two new speed sensors?

3) Why would there be a whine when driving now if the fluid was drained and supposedly refilled? The whine is not engine noise as it does not do it when revved in Park or Neutral, and it did nto do it until the speed sensors and fluid were changed.

Thanks.

Andrew

 

the wine is from no fluid. i think they forgot to add fluid after they drained it. or they added the wrong stuff. most shops have no clue about the fluids late model fords take. the tranny and transfer case use mercon the rear end synthetic 85w90 and engine synthetic blend 5w30. does the 4x4 even engage at all? there is a special way to put it into 4wd low ford made it so you can't switch right into it. you need to be stopped place the car in neutraul then switch it over to 4wd low.

 

No, the 4x4 does not engage at all now. If my regular mechanic shop can't fix it, I am taking it to the dealer tomorrow. We need the Expy for this weekend's trip. I'll call and ask about the fluid they put in.

From what I can see here on the forum, blinking lights are not good. It appears to me the AWD light should be solid when the switch is in the AWD position. This means I have had a problem since I owned it and did not know it. I wonder since the light is solid now if I have AWD and did not have it before when it was blinking?

Thanks for the info.

 

This might be stupid, but are you sure you are engaging 4wd correctly? You can go from 2WD to A4WD on the fly, but to go to 4WD you need to be in park with the brake on (at least that is the case in my 98 Navi). If you don't do this then you get the flashing light. I had the same worries as you when I got mine last year and tried it out. Turns out I was doing it wrong.

I'd just hate to see you spend the money if it is something really easy like this. Take a look at your manual for the correct procedure for your truck.

 

No, it is not stupid because all bases need to be covered. However, this is not the cause. I read the owenrs manual of this vehicle the first day I bought it because the only other 4WD vehicles I owned were real simple to use, such as my 1998 Range Rover, 1986 Bronco II, and 1976 Chevy pickup. The Range Rover you just shifted over into 4WD, waited till it beeped 3 times, and there you were. the BII and the Chevy are all manual: lock the hubs, get into neutral, and shift into $WD. This EXPY was cheap ($4.5k under book), was in good shape, and was a 4 door so it was what we were looking for. The electronic 4WD did not appeal to me and never has as to me it is way too complicated, and I am correct. From Day 1 of owning this vehicle I have always shifted into and out of AWD while driving, although only at lower speeds. If I want to shift into 4WH or 4WL I stop completely, shift into neutral, move the switch to AWD, wait a second until it engages, move the switch to 4WH, wait until it engages, and then into 4WL, waiting until it engages before dropping into drive and driving away. I do the same when leaving 4WL, always waiting until the next selection has engaged bfore moving onto the next.

So, am I correct in that the AWD light should ALWAYS be solidly lit and not flashing when in AWD?

And, what would cause the AWD light to stay lit when the switch is in either 4WD spot?

And, what would cause the whine? I asked the mechanic what fluid they put in the vehicle and he said Mercon, but granted, he is not the one who filled the transfer case up so maybe he knows but the guy doing the actual filling did not use Mercon. How to tell.......

Well, it appears it is off to the dealership tonight and hopefully tomorrow they can tell me it is a simple fix.

 

The indicator lights (A4WD, 4HI, 4LO) should NEVER blink. Blinking is bad.

You do not have to come to a stop before shifting from 2WD to A4WD or 4HI. You DO have to stop to go into 4LO.

As for the vehicle not going into 4WD... If it worked before your mechanic "fixed" it, then I'd have to say he/she did something wrong. May be as simple as something that's not plugged in. But, the new noise is kind of disturbing. I'd recommend that you check (or have it checked) the fluid levels and connectors on the transfer case.

 

Ok, the dealership diagnosed it as a 4x4 shift motor. It will cost me $526 plus tax to get it fixed. Ouch. This is on top of the $316 I paid to my mechanic to have the two speed sensors replaced. Ouch, ouch....... And you know, this Expy has never been four wheeling, strictly on road only. This better be it!!

 

Well, at least you know what it is now... maybe. If you've not already had the new shift motor installed, you might find a used one at a salvage for a lot less money.

As for using it, that might actually be a problem. You should occassionally engage 4WD to keep all the parts lubed & working.

 

I should clarify my on-road use statement. What I meant was it was not used for "fun" off-road driving. I use 4WL at least every 2 weeks because of where I live, and the fact I have not yet graded my driveway completely. That is probably why it went out: it was not used at all before I bought it and then when I started using it there she goes. And, the 4x4 works. I still have a whine but it is not as loud as it once was. My original mechanic's employee said he thinks the whine I hear but he cannot hear is because the fluid they had refilled with had not completely gone around the gears in the transfer case, etc. etc. Sounds like crap to me. I can't wait until my mechanic gets back from hunting so I can talk to him.

Now, I have another problem but that will be another post here shortly, after I search this forum for answers.

THANK YOU very much for your suggestions and help.

Andrew

 

could the whine be from the power steering? my expy (and a few i test drove when shopping for mine) has a slight whine that sounds to me like low power steering fluid (though my reservoir is full)...

just a thought

al