'93 Ranger 4.0 Stuck in 4Low
'93 Ranger 4.0 Stuck in 4Low
So I'm pretty lost at this stage. For some backstory, I've had my ranger for a little while now. It's been getting worked on in my garage for a while, first the valve cover gaskets because they were leaking very badly. Didn't drive it around after that but started great. Then I ended up doing the brakes, new pads, a new caliper/rotor and the other one was resurfaced. Took apart both 4wd hub assemblies (automatic +auto trans). I also had the dash taken apart for quite awhile attempting to solve a gas gauge issue. Finally, after all that was finished, I put the dash back together and plugged everything back in. This is when I noticed the problem. Both the 4wd and 4low lights were illuminated after I plug the wire harness for the buttons back in. I never touched them before that. I attempted to turn the 4low off (in neutral brake fully compressed) and then the 4wd. Took it for a drive and I was stuck in 4low, engine would cut and stop revving after a certain speed.
Based on research I came to the conclusion that the transfer case motor was the issue. According to multiple different sources including https://www.therangerstation.com/tec...e-shift-motor/ I took the motor apart and inspected it. As expected the plastic bushing was completely destroyed so I replaced it with a piece of vacuum hose that was cut down to the proper size. I reinstalled the motor and could hear it engage with each button press but the lights for each button remained illuminated.
I then unbolted the motor and once again and observed it with the wire harness still plugged in. It went to each of the three positions complete fine so I decided to check the peg on the transfer case that the motor mounts to. I tried moving it manually but it wouldn't budge past a certain point in 4low (with someone on the brake in neutral). I had to walk away out of frustration and came back inspired by a post and a little rage. Needless to say I went ape sh** on the t-case for a couple minutes with a rubber mallet. After that I had someone go back onto the brake in neutral and it smoothly shifted into 2hi using the vice grips.
Upon putting the motor back on, it sounded like it was working properly, making a steady noise with the shift from 4low to 4hi and then to 2hi. Despite the noise and all, the lights remained on. According to my father, he did not even see the front drive shaft engaging so it seems that it isn't even in 4wd. Went for a drive and there was no difference, all the lights were still on, engine refused to go beyond a certain speed, and anything I tried after wouldn't disengage it. I also tried driving back and forth and then attempting it. I tried going out of 4low with a wheel jacked up. Not sure what else it could possibly be. Any help would be appreciated because I'm not sure if this could be electrical or a mechanic issue within the transfer case internally.
Based on research I came to the conclusion that the transfer case motor was the issue. According to multiple different sources including https://www.therangerstation.com/tec...e-shift-motor/ I took the motor apart and inspected it. As expected the plastic bushing was completely destroyed so I replaced it with a piece of vacuum hose that was cut down to the proper size. I reinstalled the motor and could hear it engage with each button press but the lights for each button remained illuminated.
I then unbolted the motor and once again and observed it with the wire harness still plugged in. It went to each of the three positions complete fine so I decided to check the peg on the transfer case that the motor mounts to. I tried moving it manually but it wouldn't budge past a certain point in 4low (with someone on the brake in neutral). I had to walk away out of frustration and came back inspired by a post and a little rage. Needless to say I went ape sh** on the t-case for a couple minutes with a rubber mallet. After that I had someone go back onto the brake in neutral and it smoothly shifted into 2hi using the vice grips.
Upon putting the motor back on, it sounded like it was working properly, making a steady noise with the shift from 4low to 4hi and then to 2hi. Despite the noise and all, the lights remained on. According to my father, he did not even see the front drive shaft engaging so it seems that it isn't even in 4wd. Went for a drive and there was no difference, all the lights were still on, engine refused to go beyond a certain speed, and anything I tried after wouldn't disengage it. I also tried driving back and forth and then attempting it. I tried going out of 4low with a wheel jacked up. Not sure what else it could possibly be. Any help would be appreciated because I'm not sure if this could be electrical or a mechanic issue within the transfer case internally.
So I assume you saw this picture of the shift rod with shift motor removed: https://www.therangerstation.com/tec...ft_motor-2.JPG
In the picture the transfer case should be in 2High
Shift rod can only turn Counter-Clockwise to 4High from 2High, and only Counter-Clockwise from 4High to 4Low, once in 4Low shift rod can only turn Clockwise back to 4High and then 2High
Just FYI, Neutral is across from 2H, between 4H and 4L
If shift rod is OK you can use pliers to turn it from 4Low back(clockwise) to 4H and then 2H, key OFF
If you can't then shift rod is most likely broken or jammed, so transfer case will need to come off and be opened
As I think you said the shift motor can be operated while is off the transfer case, and should turn to its 3 points, and the dash lights should indicate the selection
Transfer case has no internal sensors for its position, in 1993 it just has the "brown wire" for an electric clutch, but its only used for "shift on the fly" not when stopped, or if you have manual hubs
The dash lights are operated by the 4x4 controller behind driver seat, and turned on and off based on the 5 wire position contacts in the shift motor, so if shift motor is calibrated correctly then when its contact wheel is in the 4Low position the 4x4 controller will see that and turn on the 4Low dash light
The buttons just tell the 4x4 controller what the driver wants, they have no connection to the lights
1993 4x4 wiring diagram below
In the picture the transfer case should be in 2High
Shift rod can only turn Counter-Clockwise to 4High from 2High, and only Counter-Clockwise from 4High to 4Low, once in 4Low shift rod can only turn Clockwise back to 4High and then 2High
Just FYI, Neutral is across from 2H, between 4H and 4L
If shift rod is OK you can use pliers to turn it from 4Low back(clockwise) to 4H and then 2H, key OFF
If you can't then shift rod is most likely broken or jammed, so transfer case will need to come off and be opened
As I think you said the shift motor can be operated while is off the transfer case, and should turn to its 3 points, and the dash lights should indicate the selection
Transfer case has no internal sensors for its position, in 1993 it just has the "brown wire" for an electric clutch, but its only used for "shift on the fly" not when stopped, or if you have manual hubs
The dash lights are operated by the 4x4 controller behind driver seat, and turned on and off based on the 5 wire position contacts in the shift motor, so if shift motor is calibrated correctly then when its contact wheel is in the 4Low position the 4x4 controller will see that and turn on the 4Low dash light
The buttons just tell the 4x4 controller what the driver wants, they have no connection to the lights
1993 4x4 wiring diagram below
Well I was able to get the shift rod to turn back from 4Lto 2H. The motor also seems to be shifting into proper positions according to the buttons pressed, i.e.. 4L - 4H - 2H and vice versa but not from 4L - 2H of course. The issue is that the motor engages into those positions properly (at least with the motor off because I can't tell if it is truly engage with the motor bolted on), yet the lights on the dash never go off and constantly indicate that 4hi/4low is activated.
On top of this, even when I know, or at least believe that 2H is selected on the motor, the engine will refuse to up shift. As far as I'm aware, the shift motor is calibrated correctly. I shifted the plate with the contacts slightly clockwise and the motor no longer worked. The only other thing I could think of would be to try moving it slightly counter clockwise or inspecting the 4x4 controller. I wonder if I could move the motor into a position and then slowly rotate the contact wheel and have someone in the cabin to tell me if there is any change in the indicator lights.
On top of this, even when I know, or at least believe that 2H is selected on the motor, the engine will refuse to up shift. As far as I'm aware, the shift motor is calibrated correctly. I shifted the plate with the contacts slightly clockwise and the motor no longer worked. The only other thing I could think of would be to try moving it slightly counter clockwise or inspecting the 4x4 controller. I wonder if I could move the motor into a position and then slowly rotate the contact wheel and have someone in the cabin to tell me if there is any change in the indicator lights.
The dash 4x4 lights both get 12volts with key on, fuse 7 in cab fuse box
Each bulb is grounded by the 4x4 controller to turn it on so.................if either wire has a short to ground on its way back to 4x4 controller then that bulb is on with key on
Each bulb is grounded by the 4x4 controller to turn it on so.................if either wire has a short to ground on its way back to 4x4 controller then that bulb is on with key on
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