4WD Question

[AtTheDriveIn]

As I've previously posted, I bought back my Explorer from the same guy who I sold it to. He briefly mentioned he let his jackass kid drive the truck "for a little bit". I forgot how quickly kids can destroy things..Anyways I bought it back for $800 so I really can't complain.

So two years ago a car shop started mistakingly towing my truck and (this is good.) instead of knocking on my door, they pulled the truck up onto the flatbed in park. My mom ended up calling the cops and the owner of the car shop came down to her house. My mom's resolution to the problem was to have the shop throw a valid inspection sticker on it and she would let bygones be bygones. (Great huh?) Well the truck was in her name so who was I to say anything?

Well for about two weeks the 4wd high and low light would randomly come on and off while driving and then one day the truck was stuck in 4wd. (The light never came back on.) I worked at a "car shop" (I use that term loosely and you'll see why.) and my boss's solution to the problem was to remove the 4wd driveshaft where he convinced me this could be a permanent solution and no damage would be done. I was broke so I wasn't going to argue and the man lives in his own little world. (His solution to current draws on cars is just to install a kill-switch.) My wife was driving the truck at the time and I told her to let me know if she heard any noises. She never mentioned a peep to me about any noises so I totally forgot about the mickey-mousing.

Fast forward two years ahead and I have the truck again. I still have the 4wd driveshaft in the back of the truck and I'd like to rid this poor vehicle of all its mickey-moused "repair" jobs. Whenever I drive the truck I notice this ticking sound coming from the 4wd transfer case when the truck is accelerating up to 35mph and then the sound goes away even if I accelerate.The steering wheel/truck shudders when I cut the wheel hard when it's at a dead stop like it used to when it was stuck in 4wd. Also it's worth noting that even though the 4wd switch is on AUTO, only 4WD HIGH lights up on the dash when I turn the knob and 4WD LOW doesn't even light up. My question is this : Is there a way to disengage the 4WD so the transfer case isn't in 4WD? I didn't know if there was an electronic way to send a message to the transfer case to say "Hey get out of 4wd" like the way the AUTO function switch is supposed to. I'm really trying to avoid replacing the 4wd transfer case since I'm not in the financial situation to do so until about November. I have a feeling that the moronic tow truck driver fried that transfer case but I figured I'd ask on here first.

Thanks.

 

[albi1cnobi1]

Your truck has the 4405 control-trac transfer case. If you have removed the front drive shaft then there is no way for the truck to be in 4wd. The t-case may be, but it won't matter as there is no way to send power up front. As for the 4wd lo light not coming on, there is a procedure for shifting into 4wd lo. From either 4auto or 4hi you have to come to a complete stop, shift the tranny into neutral, and then shift the t-case into 4lo. Only then will it shift into 4lo and illuminate the 4lo light. Follow the same procedure to shift out of 4lo. If the t-case is actually damaged as a result of that bone head tow driver, then there might be a larger problem. I'll give you a quick tutorial on the 4405 case. Unlike a normal t-case the 4405 does not actually "switch" from 4auto to 4hi. The t-case has an electric clutch inside. When in 4auto the t-case senses wheel speed via sensors on the front and rear t-case outputs, and when they sense a difference(wheel spin) the GEM(generic electronic module) tells the t-case to slowly engage that clutch(changes the duty cycle, from 0% to 100% as needed) until it no longer senses any wheel spin. When you shift into 4hi the GEM tells the t-case to fully engage the clutch, effectively giving you 4hi. When you shift into 4lo, the clutch stays engaged and the t-case switches the gearing to lo. The question of the wheel shudder is not related to the t-case. If the front drive shaft is not in then there is no connection to the front wheels. That is another issue all together. The ticking however could be the t-case. And to end this long winded post(lol) the only way to ensure that the t-case doesn't go into either 4hi or 4lo is to unplug the shift motor from the t-case. If I remember correctly this will also disconnect the infamous "brown wire" and this will keep the internal clutch from engaging. The only draw back from this is that the GEM sees this as a fault and will blink the 4hi and 4lo lights on and off as a fault code. It's not going to hurt anything, but can be annoying. If that doesn't bother you, then thats the way to go. Good luck, and if you have any questions ask away.

 

[AtTheDriveIn]

Your truck has the 4405 control-trac transfer case. If you have removed the front drive shaft then there is no way for the truck to be in 4wd. The t-case may be, but it won't matter as there is no way to send power up front. As for the 4wd lo light not coming on, there is a procedure for shifting into 4wd lo. From either 4auto or 4hi you have to come to a complete stop, shift the tranny into neutral, and then shift the t-case into 4lo. Only then will it shift into 4lo and illuminate the 4lo light. Follow the same procedure to shift out of 4lo. If the t-case is actually damaged as a result of that bone head tow driver, then there might be a larger problem. I'll give you a quick tutorial on the 4405 case. Unlike a normal t-case the 4405 does not actually "switch" from 4auto to 4hi. The t-case has an electric clutch inside. When in 4auto the t-case senses wheel speed via sensors on the front and rear t-case outputs, and when they sense a difference(wheel spin) the GEM(generic electronic module) tells the t-case to slowly engage that clutch(changes the duty cycle, from 0% to 100% as needed) until it no longer senses any wheel spin. When you shift into 4hi the GEM tells the t-case to fully engage the clutch, effectively giving you 4hi. When you shift into 4lo, the clutch stays engaged and the t-case switches the gearing to lo. The question of the wheel shudder is not related to the t-case. If the front drive shaft is not in then there is no connection to the front wheels. That is another issue all together. The ticking however could be the t-case. And to end this long winded post(lol) the only way to ensure that the t-case doesn't go into either 4hi or 4lo is to unplug the shift motor from the t-case. If I remember correctly this will also disconnect the infamous "brown wire" and this will keep the internal clutch from engaging. The only draw back from this is that the GEM sees this as a fault and will blink the 4hi and 4lo lights on and off as a fault code. It's not going to hurt anything, but can be annoying. If that doesn't bother you, then thats the way to go. Good luck, and if you have any questions ask away.

Wow that was the information I was looking for! Thank you! My question is where exactly is the shift motor on the transfer case?

 

[albi1cnobi1]

No problem. The shift motor is on the back side of the t-case, next to where the rear drive shaft comes out. It has a square 16 pin plug mounted to the bracket. Here is a pic of that plug.

Here is a shot of the whole t-case. The front is facing the bottom of the picture. Top right you can see the shift motor on the rear of the t-case.

All you need to do is un-plug the harness at that plug. If I were you I would somehow try to seal those open plug ends. Maybe tape a zip lock or something similar over them. You don't want to try to use it again after a period of time and find out your plugs are all corroded. Just a thought.

 

[AtTheDriveIn]

No problem. The shift motor is on the back side of the t-case, next to where the rear drive shaft comes out. It has a square 16 pin plug mounted to the bracket. Here is a pic of that plug.

Here is a shot of the whole t-case. The front is facing the bottom of the picture. Top right you can see the shift motor on the rear of the t-case.

All you need to do is un-plug the harness at that plug. If I were you I would somehow try to seal those open plug ends. Maybe tape a zip lock or something similar over them. You don't want to try to use it again after a period of time and find out your plugs are all corroded. Just a thought.

WOW. Thank you! I'll be unplugging that bad boy on Saturday!