2003 sierra 2500. front drive shaft will not spin with a load against front end. new actuator, it's locking in. new encoder motor, it;s locking in. just had new clutch plates and bearings and seals put in transfer case. without load against frontend, front shaft will spin tires. it is a nvg246 rpo 8 transfer case. any help will be good

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...

Sounds like you need a front axle actuator. This actuator bolts to the side of the front differential housing. It is electrically engaged. You can purchase them online starting at about $40

Not good! there is a sensor in your transfer case that senses that you are now in four wheel drive if your transfer case does not lock in it will set a code and the light will flash and default back to two wheel drive. check the fluid level in the transfer case and front differential for a sign of internal failure. that is causing the grinding sound.

Sounds like the electrical actuator is bad on the front axle.

If yours is electric shift, you will need a new shift solenoid installed in the tranny.

i have the same truck and mine works

you may have to replace your trasfer case control module its right under dash driver side easy to access mine just went out it was throwing c0359 code 4 low cirut and service four wheel drive would come on dash although the 4wd works great it just throws the code.

Sounds like the chain in the transfer case has broke or the linkage is out of adjustment

Take the front axle actuator out of the axle. Plug it back in and have some one push the 4x4 button. The actuator should move, it's a liniar motor. If it doesn't then the actuator is bad or there is a wiring problem. If it does there is a problem in your front diff or some where else in the system.
I'd take a guess and say it's the front actuator.

I have found that when you are going to engauge 4x4 high, it is best to only be going about 3 miles an hour. Not faster, not stopped. It likes some movement to help it mesh. I've had perfect shifts since I started this. Hope it helps. Wade.