Annoying 4x4 Problem

[Aussie_jase]

Hi guys,
Just wanted to know your opinions on the following problem i have.

My 97 XLT has a most annoying little problem it likes to throw at you. Normally with the 4x4 system , if i am just sitting still on the pavement after driving around for a while and engage the 4x4 WITHOUT MOVING on the hard surface, it will engage perfectly. I have noticed it will not change into 4x4 low unless the brake is pushed. However, if i take the truck onto a beach, failry soft sand so its getting a pretty hard workout, and drive around for a bit ( please note i do let my tyres down to 15 PSI ), i have found that when i come off the beach and hit the hard surface, when i go to disengage the low range, it doesnt want to do it. The module that normally clicks under the dash doesnt click at all and the brake it pushed in?? Its as if the car doesnt know i have told it to disengage. Im not sure if it is the dash switch, the module that changes the 4x4 range, which im pretty sure is the GEM module, or the switch on the brake pedal. Does anyone have any ideas?? I found that when i jiggle the wires under the steering column it clicked and it changed for me eventually, but it is most annoying and a bit scary since the beach is a good 30 min drive from home and a bit far to be driving in low range and on hard surface. I am also wondering if the battery has anything to do with it , since when i got it checked they said it was only holding about 11.5 volts?? Could this affect the system??

Any help is greatly appreciated.

 

[bluevolume]

It is a little unclear exactly how you are operating the 4x4 system, especially when going into low range. I'm assuming that you do put it in neutral first? Having the vehicle in neutral and having the brake firmly depressed are very important, given the close tolerances of the transfer case. It is not designed to shift while there is any movement going on.

You said that jiggling the wires would make it shift out of low range? That's hard to explain, I guess I would follow the wires to each end and check for bad connections -- maybe a seat has gone bad in the fusebox.

Finally, while your battery may need to be replaced, I don't think it is part of this problem. Your alternator should be providing more than enough juice to run the solenoids in the tranny.

 

[Aussie_jase]

Does the GEM module have any known problems of playing up?? And i do have it in neutral and my foot on the brake when changing range selection. I was also wondering if the gearstick has a neautral sensor on it that the GEM picks up to tell it it's in neutral?? Its seems fine whenever im not on the sand giving it a hard time, but it sometimes does work even when i am. Very confusing and frustrating problem. It could even be the 4X4 switch itself maybe?? Ford dont seem to want to help out at all.

 

[TPLYNCH]

Sometimes shift motor forgets where it is, especially if not used frequently. T/F case connections might be loose, or the shift motor dirty. You can clean the motor following instructions at this site Dead Link Removed

Disconnecting the battery for ~15minutes works sometimes when it's stuck - resets the computer. If that doesn't work, you can tap the motor w/a mallet.