1997 Explorer with 4WD issues.

[klorti]

Hey everyone! I'm new to the forum, although I've come here many times recently. My girlfriend has a 97 ford explorer and I'm trying to help her out with a problem, hopefully some of you experts out there can provide some insight.

The vehicle has around 145k miles on it, and it needs a little work. Recently the 4wd and 4wd low lights started flashing 6 times every couple of minutes, so I did what most suggested and took out the transfer case shift motor and speed sensors and cleaned them all up. After putting them back in, the lights stopped flashing and when I switch from 4wd high to 4wd low I can hear the transfer case shift motor doing it's work. Now if I switch from 4wd high - 4wd auto (and vise versa) it doesn't clunk, it makes no sound whatsoever but the dash light indicates it's working. Also while driving down the street I noticed a new whining noise, as if it's stuck in 4wd high and can't get into 4x2 mode. It's drivetrain dependant, because if I just sit in park and rev the engine it doesn't make the whining sound. Also when making hard turns it will make a clunking sound as if trying to switch into 4wd.

I'm planning on jacking up the front end tomorrow (it just started raining) and checking to see if the front wheels spin freely or if their locked into place, this would indicate it would still be in 4wd correct? I'm also going to check the wheel bearings whilst I'm down there, but is there anything else I should be looking for? CV joints maybe? If the transfer case was messed up internally would it create these symptoms? Is it normal not to hear anything when switching between 4wd Auto and 4wd high?

Any input is greatly appreciated! Thanks in advance,

- Klorti

 

[Rick]

I changed the title of your thread to make it more descriptive of the problem. Hopefully someone will have an answer for you. I'm not very familiar with the workings of the 2nd Gen transfer case.

 

[BrooklynBay]

Welcome to this forum! I've moved your thread into the transmissions & transfer cases section. Did you test the shift motor while it was out of the vehicle, and the electrical connector was still plugged into it?

 

[klorti]

Thank you! And no I didn't test it while it was off the vehicle, guess that would've been a smart move. Good thing it's easy to get off

I'll check it out and report my findings. Thanks again.

 

[ragajungle]

Also when making hard turns it will make a clunking sound as if trying to switch into 4wd.


- Klorti

If it is binding up and clunking when turning sharp and making wiring sounds at upper speeds it is definitely stuck in 4. There is a good chance that either when you reassembled the shift motor the armature/wafer (if it is anything like the gen 1's) is thinking 4hi is it's home position (default 2wd). I would see if a different shift motor would help.

ALSO I am not too familiar with gen 2 manual tcases but if it is anything like that of the gen 1's there may be a arrow stamped into the casting beneath the shift motor mounting point indicating which is hi, low and 2. Some people have manually shifted to 2 with a pliers and left the shift motor off. hope this helps
-Mike

 

[klorti]

Alright, so I finally got back under there and checked it out. Wheel bearings seem fine, it's still making the whining noise while driving down the road. I checked all the fluids and fuses and everything is fine. With the front wheels off the ground they spin freely despite the backwheels on the ground, so am I correct in assuming I'm in 2wd? While driving the 4 hi and 4 low dash lights started flashing again, so obviously there's a problem in the system somewhere. I've read somewhere else that there are 3 relays by the gas peddle that could be the cause of this as well, replacing them may be my next course of action.

Took the shift motor off and it only changes in two positions - 4 hi and 4 low. Here's a picture of the transfer case side:

From what I gather the shaft only changes position between 4 hi and 4 low, correct? Does the "N" mean it has to be in neutral to shift into 4 low or is that where it's supposed to be when I'm driving in Auto 4wd?

 

[klorti]

Well just for anybody else that happens to search this issue, Here's an update.I took it to a dealership to have them scan the codes to determine the problem and it ended up being the transfer case speed sensors. They charged me almost $600 to fix it, which is outrageous but since it was stuck in 4wd I didn't want to chance damaging the drivetrain anymore.

Part numbers are:
1L2Z7F293AB - $128.16
1L2Z7F293BA - $109.38

Thanks for the help everyone.

 

[BrooklynBay]

Thanks for the update!

 

[albi1cnobi1]

Just an informational post. On the 2nd gen control trac t-cases you are correct there is no actual shift from 2wd(4auto) to 4hi. The position on the case that says Hi is 2wd(or 4auto) until the speed sensors detect wheel spin and engage the clutch. The TOD relay(torque on demand) varies the duty cycle of the voltage to the clutch depending on the amount of wheel slippage. When you shift to 4hi the TOD relay puts the clutch at 100% duty cycle to give you 4wd. When you switch to 4lo the shift motor then moves the shaft to lo engaging the shift collar to give you 4lo. Hope that helps in understanding how this case works. Thats why when you shift from 2wd/4auto to 4hi you don't hear the shift motor because it's not actually moving. The "N" position is there for a dealer installed option for a neutral towing, so the vehicle can be flat towed. In normal operation the shift motor shifts right by it not using it.