The ruber boot on front drive shaft keeps ripping, the transfer case was rebuilt, the motor mounts are fine and the front axle is not lose. the explorer is not lifed. There have been 4 driveshafts put into this suv. The same thing happens the boot rips stones and dirt get into cv joint.Can anybody help me?

Which of these does your vehicle have ?

Transfer Case - NVG 233-NP1 (Two Speed Selectable)
Transfer Case - NVG 136-NP4(One Speed Automatic)

The New Venture Gear NV233 is an electronic shift transfer, with the following three modes of operation, Two-wheel drive high range, Four-wheel drive high range, Four-wheel drive low range. The gear reduction for low range is provided by a planetary gear set. The floor-mounted shifter has been eliminated. A switch, located on the upper right side of the instrument panel, is used to select the operating range. The indicator lamps on the switch show the current mode of operation. When the four-wheel drive has been selected, the four-wheel drive indicator lamp on the switch is designed to turn on when the front axle has engaged.


Automatic Transfer Case
The single speed automatic transfer case system shifts automatically from rear wheel drive to four wheel drive when the transfer case shift control module (TCSCM) senses the difference in rotation speed of the front propeller shaft and the rear propeller shaft . Two vehicle speed sensors, one located at the rear output shaft area of the transfer case, and the other, located at the front output shaft area of the transfer case, send front and rear propeller shaft rotation speed information to the TCSCM.
When the front and rear output shaft rotations remain the same, the TCSCM sends pulse width modulation signals to the encoder/motor to keep the transfer case in rear wheel drive. When the front and rear output shafts rotations are different, the shift control module sends pulse width modulation signals to the encoder/motor to engage the transfer case into four wheel drive.
The system will automatically transfer a percentage of torque to either the front or rear axles as required to stop all wheel slip. When the front and rear output shafts rotations return to the same speed rotation, the shift control module sends pulse width modulation signals to the encoder/motor to position the transfer case back into rear wheel drive.
When the transfer case is engaged into four wheel drive, a lamp indicator on the instrument cluster will light. The automatic transfer case system is completely automated, no transfer case control button switching system is required.

Do you know what diagnostic trouble code's are ?

DTC C0300 Rear Speed Sensor Malfunction
DTC C0305 Front Speed Sensor Malfunction
DTC C0308 Motor A/B Circuit Low
DTC C0309 Motor A/B Circuit High
DTC C0310 Motor A/B Circuit Open
DTC C0315 Motor Ground Circuit Open
DTC C0374 General System Malfunction
DTC C0376 Front/Rear Shaft Speed Mismatch
DTC C0550 ECU Malfunction
DTC C0611 VIN Information Error
DTC C0895 Device Voltage Malfunction

Not OBD2 engine code's .

The Selectable Four Wheel Drive (S4WD) Front Axle consist of the following components:
• Differential Carrier Housing
• Differential Case Assembly
• Inner Axle Shaft
• Intermediate Shaft Bearing Assembly (located on the right side of the oil pan)
• Electric Motor Actuator
The front axle on Selectable Four Wheel Drive (S4WD) model vehicles uses a disconnect feature mounted on the right side of the oil pan in order to engage and disengage the front axle. When the driver engages the 4WD system, the Transfer Case Control Module sends a signal to the electric motor actuator to energize and extend the plunger inside. The extended plunger moves the clutch fork and clutch fork sleeve across from the clutch fork outer gear that is splined to the right side wheel drive shaft to the clutch fork inner gear that is splined to the inner axle shaft. The locking of the two gears allows the axle to operate in the same manner as a semi-floating rear axle. A propeller shaft connects the transfer case to the front axle. The differential carrier assembly uses a conventional ring and pinion gear set to transmit the driving force of the engine to the wheels. The open differential allows the wheels to turn at different rates of speed while the axle continues to transmit the driving force. This prevents tire scuffing when going around corners and premature wear on internal axle parts. The ring and pinion set and the differential are contained within the carrier. The axle identification number is located on top of the differential carrier assembly or on a label on the bottom of the right half of differential carrier assembly. The wheel drive shafts are completely flexible assemblies consisting of inner and outer constant velocity CV joints protected by thermoplastic boots and connected by a wheel drive shaft.

How To Install Repair Replace 4x4 Front Axle Actuator Chevy Trailblazer...

No 4X4 switch on the instrument panel ?
Automatic Transfer Case
The single speed automatic transfer case system shifts automatically from rear wheel drive to four wheel drive when the transfer case shift control module (TCSCM) senses the difference in rotation speed of the front propeller shaft and the rear propeller shaft . Two vehicle speed sensors, one located at the rear output shaft area of the transfer case, and the other, located at the front output shaft area of the transfer case, send front and rear propeller shaft rotation speed information to the TCSCM.
When the front and rear output shaft rotations remain the same, the TCSCM sends pulse width modulation signals to the encoder/motor to keep the transfer case in rear wheel drive. When the front and rear output shafts rotations are different, the shift control module sends pulse width modulation signals to the encoder/motor to engage the transfer case into four wheel drive.
The system will automatically transfer a percentage of torque to either the front or rear axles as required to stop all wheel slip. When the front and rear output shafts rotations return to the same speed rotation, the shift control module sends pulse width modulation signals to the encoder/motor to position the transfer case back into rear wheel drive.
When the transfer case is engaged into four wheel drive, a lamp indicator on the instrument cluster will light. The automatic transfer case system is completely automated, no transfer case control button switching system is required.

Do you know what DTC'S - diagnostic trouble code's are ?
Auto part stores can't read these , your best bet take it to a qualified repair shop . One that has the knowledge an diagnostic equipment .
DTC C0300 Rear Speed Sensor Malfunction
DTC C0305 Front Speed Sensor Malfunction
DTC C0308 Motor A/B Circuit Low
DTC C0309 Motor A/B Circuit High
DTC C0310 Motor A/B Circuit Open
DTC C0315 Motor Ground Circuit Open
DTC C0374 General System Malfunction
DTC C0376 Front/Rear Shaft Speed Mismatch
DTC C0550 ECU Malfunction
DTC C0611 VIN Information Error
DTC C0895 Device Voltage Malfunction
Without proper factory service an repair info. an diagnostic tools

Check the 4x4 wiring ground (directly behind the left front tire, mounted to the body). If the front axle actuator is still good, this is usually the source of frustration. Put some RTV Gasket sealer on the nut and bolt after you replace them to help keep it from corroding as fast.

Operationally vacuum shifts the front axle between 2WD and 4WD mode. The GEM ( Generic Electronics Module ) applies ground to the solenoid needed for the mode selected on the switch ( for ESOF ) or when the transfer case shift lever is moved ( MSOF ).The contact plates in the transfer case signal the GEM that the transfer case is engaged, and the Vacuum solenoids need to be activated ( either 2WD to 4WD or 4WD to 2WD ).

Lift and support the front of the truck so the front wheels are off the ground ( take safety precautions, chock wheels, jack stands, etc )
Key on, engage 4x4 and try to turn the front drive shaft.
- If it turns it is a problem with the transfer case.
- If it doesn't it is a front axle engagement problem ( this is what you seem to have, the transfer case is engaged and will drive the front shaft mine was a key on engine off test ).

- If the front drive shaft does not turn :
•With the truck running ( with front wheel back on the ground ), switch from 2WD to 4WD and back again, the vacuum shift motor should move the lever on the front axle.

-- If the vacuum shift motor does not move:
1.Check for vacuum on the lines while shifting between modes. Pink vacuum line is 2WD mode, Light Blue vacuum line is 4WD.
2.Check the fuses for the 4WD system and the solenoids.
3.Check the vacuum lines from the vacuum shift motor to the solenoids on the firewall.

4.Check the vacuum lines from the solenoids to the vacuum reservoir box behind the battery.
5.Check the vacuum reservoir box for cracks.
6.Typical solution is the vacuum lines ( to the solenoids or to the vacuum shift motor ) are cracked or the vacuum shift motor has a cracked diaphragm and has water in it.
7.Could be the shift plate contacts in the transfer case are corroded / not making good contact, and not activating the solenoids.


Usually the case is cracked vacuum lines from the solenoids, the next common is a cracked vacuum reservoir box, and 1 time I have seen the mount for the vacuum disconnect motor broken ( motor floating free so it could not push against the axle )

Two things, if you get a vibration when you are decelerating( an indication of shaft problems) you may need to replace your 3 motor mounts. But more important, most aftermarket rebuilt shafts are junk. Buy only new or Mopar rebuilt axle shafts. Anything other than Mopar new shafts or Mopar rebuilt shafts(sometimes Mopar rebuilt can be bad too) and you are pretty much guarantying that you will be replacing the shaft again with in 6 months. I own a 1993 Voyager and have replaced a dozen axles. The problem stopped with the OEM parts. Forget about the lifetime warranty offered with auto store axles, unless you enjoy replacing axles.

yes but make sure you don't in gauge the front axle

Lift and support the front of the truck so the front wheels are off the ground ( take safety precautions, chock wheels, jack stands, etc )
Key on, engage 4x4 and try to turn the front drive shaft.
If it turns it is a problem with the transfer case.
If it doesn't it is a front axle engagement problem.

I am going to guess the drive shaft will not turn, and the problem is the shift disconnect motor on the front axle, or the shift solenoids.
The shift motor looks like this


The shift solenoids look like this :


You can check the shift solenoids with a vacuum gauge. The blue vacuum line is the 4WD operation, the pink is the 2WD operation. Pull the vacuum line at the shift disconnect motor, and install the vacuum gauge. Shift into 4WD and the vacuum should be on the line, and hold. If not could be the disconnect motor or the vacuum line to the motor.

Could also be the shift motor in the transfer case, but with the 4x4 light on the cluster lighting up, the transfer case should have shifted, the confirm comes from the transfer case to illuminate the 4x4 indicator on the cluster.

You know for a fact no power is being sent to the front axle? This transfer case only sends power to the front axle when the rear axle is slipping. Are there any unusual noises in the front axle?

If it is the transfer case, replacing it is not too big of a deal. If you are the least bit confident of your abilities, then you can do it yourself. I believe you have the NP242 transfer case, but I could be wrong. There will be a tag on the back side of the case, facing the rear axle, to the left of the drive shaft. On that tag, it will tell you which case you have. You can either have yours rebuilt, or buy a replacement either new or used.

To remove the t-case, first drain the fluid. Next remove the front driveshaft by removing the four bolts holding the u-joint in place. Then remove the rear drive shaft by doing the same as the front driveshaft, only this time it's at the rear differential. Once the drive shaft is free, support the full weight of the driveshaft, not that heavy, and pull it out of the t-case and set aside. Disconnect the shifter linkage and wiring harness. Next, remove the bolts that connect the t-case to the t-case cross member. Lift slightly and support the tranny/t-case assembly and remove the cross member. The t-case isn't very heavy, but you don't want it falling on your head, so remember to support it as you remove the bolts that connect it to the rear of the tranny. Once you bring it out from under the Jeep, and it's rebuilt or you have another unit to replace it, installation is the reverse of removal. Just remember to refill the t-case with the proper fluid.

change actuator in front hub water gets in there freezez and ruber seal rips part only 120.00 bucks not hard to change beat upper ball joint take of spindle nut think it was 5/8 3 bolts in back should fall out