What type of oil do i need for a 1995 chevy silverado transfer case also if you know what gear oil should i use for the front and rear axles

You have AWD? full time all-wheel drive.
Transfer Case Description and Operation
The Borg Warner (BW) model 4481, RPO NR3 transfer case is a one-speed, full time, all wheel drive (AWD), transfer case. The transfer case provides power to both axles, through an external planetary type differential, which has two different sets of pinion gears. The planetary differential provides a 40/60 torque split, front/rear, full time. This means both axles are constantly being driven for maximum traction in all conditions.
The transfer case external type planetary differential functions the same as a typical rear axle differential. The transfer case differential pinion gears function as the spider gears, and the sun gears function as the side gears.
The following actions occur because of the planetary differential:
• If the vehicle is on a hoist, the front propeller shaft can be rotated by hand.
• The vehicle cannot be driven if one propeller shaft is removed.
• Operating the vehicle on the hoist can damage the differential pinion gears, by over-spinning.
• Operating the vehicle with one propeller shaft removed causes over-spinning of the differential pinion gears.
The BW 4481 design of the planetary differential allows the use with the Vehicle Stability Enhancement System (VSES) vehicles. The VSES takes use of the planetary differential, by applying braking to a tire that has less traction and dividing the engine torque to the other axle.
The BW 4481 case halves are high-pressure, die-cast magnesium. Ball bearings support the input shaft, the front output shaft, and the rear output shaft. The transfer case requires DEXRON®III ATF GM P/N 12378470 (Canadian P/N 10952622), which is red in color.

This system does not have an encoder motor.

How to Remove a Chevy Blazer Rear Transfer Case The transfer case on a Chevrolet Blazer is underneath the vehicle, mounted to the rear of the transmission. On four-wheel drive vehicles, the transfer case takes power generated by the engine and channeled through the transmission and directs it to the front and rear drive axles. Over time, the gears and bearings inside the transfer case can wear and the transfer case must be rebuilt. The transfer case on this vehicle must be removed before it can be serviced.
Things You'll Need

• Wrench set
• Floor jack
• Jack stands
• Socket set
• Masking tape
• Marker
• Needle-nose pliers

Hide Instructions

1. Removing the Driveshafts
   • 1 Disconnect the ground cable from the negative battery terminal, by using a wrench to loosen the retaining bolt and pulling the clamp off the terminal.
     

2 Raise the vehicle and support with jack stands placed underneath the frame.

3 Drain the transfer case. Locate the drain plug near the bottom of the transfer case. Place a waste oil collection pan underneath the plug and use a socket to remove it. Once all the fluid has drained out, reinstall the plug.

4 Remove the bolts that connect the rear driveshaft to the rear axle yoke using a socket. Lower the driveshaft, and slide it backward underneath the rear axle to disengage it from the transfer case. Remove it from the vehicle.

5 Remove the bolts that connect the front driveshaft to the front axle yoke using a socket. Lower the driveshaft, and slide it forward underneath the front axle to disengage it from the transfer case. Remove the driveshaft from the vehicle.

Removing the Transfer Case

• 6 Label and disconnect the electrical wires and vacuum lines connected to the transfer case. Use masking tape and a marker.
  
• 7 Remove the transfer case shifter rod. Using needle-nose pliers, remove the clip that connects the shifter rod to the transfer case. Slide the rod away from the transfer case.
  
• 8 Position a floor jack underneath the transfer case. Raise it enough to take the weight of the transfer case off the transmission.
  
• 9 Remove the bolts that connect the transfer case to the transmission using a socket or wrench.
  
• 10 Slide the transfer case rearward to disengage it from the transfer case. Lower the floor jack, and remove the transfer case from the vehicle
  

that's funny, there is no electrical 4wd, its got gears.
all have gears.
what some do is have electric acatuators to shift or just to
engage front locking devices.
who to tell on old car>
1: look, is the front axle with outboard hub lockers, manual; or auto?
bingo 100% mechanical,
under newer cars the front axle (look at it) see motor pump or vaucum
lines that run the auto locking axle.
2: look at shifter, is it a lever, , with linkage to transfer case, bingo mech. if only switches, its electrical.

see FSM
or alldata.com
i look for you.
and......
I see manual locking front hubs, (no elect)
and the transfer case?
most are linkage
but there are 2 transfer case options
RF1A (counter gears) or VF1A planetary gear reduction unit. transfer case.
the dash has a simple idiot lamp that means the tranfer
case thinks its in 4wd but never really knows for sure.
its just a switch. i never look at it. i feel my gears at all times
by seat of pants.

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...

FRONT AXLE ± 0.3 L (2 oz.)
C200F
1.7L (57.5 Ounces)
C200FE
1.7L (57.5 Ounces)***
REAR AXLE ± 0.3 L (2 oz.)
C213R
2.07L (70 Ounces)
C213RE
2.24L (75.5 Ounces)***
*Nominal refill capacities are shown. A variation may be observed from vehicle to vehicle due to manufacturing tolerance and refill procedure.
** Includes 0.9L (1.0 Quarts) for coolant reservoir.
***ELSD - add 118 ml (4 Ounces) of friction modifier.
Transfer Case (3.7L Engine)
Mopar® ATF+4 Automatic Transmission Fluid
Transfer Case (3.0/4.7/5.7L Engines)
Mopar® NV 247/245 Transfer Case Lubricant
Transfer Case (6.1L Engine)
Mopar® NV146 Transfer Case Fluid. Usage of other fluid/lubricants is NOT recommended.
Axle Differential (Front-Rear)
Mopar® Synthetic Gear & Axle Lubricant SAE 75W-140 (API-GL5) or equivalent with friction modifier additive.

Your brake an CV joint issue can't an won't cause your 4X4 problem . The 4x4 system has a control module which supply's B+ voltage to the switch . Checking for codes in the 4X4 control module should have been the first step . Your best bet , take it to a qualified repair shop . You don't have the knowledge or test equipment to fix this.
SERVICE indicator (4WD/AWD) Lamp
The SERVICE indicator (4WD/AWD) lamp is an integral part of the cluster and cannot be serviced separately. This lamp is used to inform the driver of the vehicle of malfunctions within the automatic transfer case (ATC) system. The SERVICE indicator (4WD/AWD) lamp is controlled by the transfer case shift control module via CKT 1567.

Transfer Case Shift Control Module
The transfer case shift control module uses the VIN information for calculations that are required for the different calibrations used based on axle ratio, transmission, tire size, and engine. The system does not know which calibration to use without this information.
The direct battery supply line (CKT 1640) provides the power to the module and motor circuitry.
Transfer Case Encoder Motor
The transfer case encoder motor consists of a permanent magnet (PM) DC motor and gear reduction assembly. It is located on the left hand side (drivers side) of the transfer case. When activated it turns the sector shaft of the transfer case (clockwise or counter clockwise) to shift the transfer case. The encoder motor is controlled with a pulse width modulated (PWM) circuit within the transfer case shift control module. This circuit consists of a driver on both the Motor A and Motor B circuits. The encoder motor is bi-directional to allow the motor to shift the transfer case from 2HI or 4HI to NEUTRAL and 4LO positions.
Do you know what DTC'S are ?
DTC B2725 ATC Mode Switch Circuit Malfunction
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 C0323 T-Case Lock Circuit Low
DTC C0324 T-Case Lock Circuit High
DTC C0327 Encoder Circuit Malfunction
DTC C0367 Front Axle Control Circuit High
DTC C0374 General System Malfunction
DTC C0376 Front/Rear Shaft Speed Mismatch
DTC C0387 Unable to Perform Shift
DTC C0550 ECU Malfunction
DTC C0611 VIN Information Error

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

Use ATF+4

Do not use Dexron or Mercon

cardan centering bearing
point bolts needed to be removed that connects D.S.to transfercase

Here are the Fluid CAPACITIES & MORE:
Engine, with filter..........4.6 quarts[1]
Cooling System, Initial Fill..........12.0 quarts
Automatic Transmission, Total Fill
4 speed 4L60, 60E..........11.0 quarts
Manual Transmission, NV1500..........5.7 pints
Manual Transmission, NV3500..........4.2 pints
Differential, with 8.6 ring gear Rear..........4.0 pints
Differential, with 7.25 ring gear Front..........2.5 pints[2]
Differential, with 8.25 ring gear Front..........4.2 pints[2]
Differential, with 9.25 ring gear Front..........5.9 pints[2]
Differential, Front..........2.5 pints
Differential, Rear..........4.0 pints
Transfer Case,BW4472..........2.5 pints
Transfer Case,NV136/236/246..........4.0 pints
Transfer Case,NP207..........4.6 pints
Transfer Case,NP231, NP233..........2.3 pints[3]
Transfer Case,NV231/233..........2.1 pints[3]
1. After refill check oil level.
2. Do not use synthetic lubricant in axles using RTV sealant.
Synthetic lubricant will chemically atack RTV sealant.
3. Identification: check tag on case.