1999 chevy tracker 2.0 engine with auto transmission. 4 wd shifts fine into the transfer case but will not engage in the front pumpkin. the front drive shaft spins but the front axles do not.

. This could be due to a malfunctioning locking hub control system, which is responsible for engaging the front wheels . Another possibility is that the front axle actuator is faulty . The rear breaks may have seized, another possibility, after the break was on so long.. Regarding grinding, It's possible that the transfer case has been damaged due to lack of use or that there is a problem with one of the gears inside.About the power issue, there could be an issue with the drivetrain. It's possible that one of the axles has become disconnected or that there is a problem with one of the differentials. You mentioned that both driver side and passenger rear wheels are stuck, which could indicate a problem with one of these components. I recommend taking your vehicle to a certified mechanic for diagnosis.

Check the actuator under the battery. make sure that it's working and pulling on the cable to lock the front hub. If it is and the front wheels are not locking then the clip at the front pumpkin (differential) may be broken or the fork that engages the axle. If everything looks good and the actuator is not working, inspect the vacuum line to the 4wd vacuum switch on top of the transfer case (drivers side) and then work your way to the vacuum line to the engine compartment. There is a T vacuum line by the ABS unit on the drivers side and inspect the lines there and the vacuum canister in the fender. Good luck and keep me posted and hope it's a simple vacuum line that went bad and not the front pumpkin.

That depends a lot on how your truck is equipped. GM uses several different 4 wheel systems including AWD, Part-Time 4WD, Full-Time 4WD, and ON-Demand AWD. Then there is another version used on some trucks that is a combination of 4WD and On Demand AWD. - it gets a little confusing but each system as slightly different charachteristics.

Genericly speaking, if you have the push-buttons on your dash that say "4-HI", "4-LO", and "2HI" and/or Auto-4WD , the transfer case has an electronicly-controlled stepper motor which shifts the transfer case into the selected mode. An electric solenoid/actuator then engages/disengages the front differential for 2-Wheel or 4-Wheel modes. One push of the button and it shifts the transfer case and engages the front differential.

That's much easier than the old days when you had to stop the truck, get out (Sometimes in the middle of a big mud hole) and lock the front hubs then get back in and play with the lever in the floor to get the transfer case to shift into the desired mode.

Well we don't know what size engine your vehicle has or weather it is a auto transmission or manual but here are the capacities.
Auto transmission
4 speed- 4wd 7.5 quarts
4 speed 2wd 7.8 quarts
Manual transmission 2 wd 4.0 quarts
Manual transmission 4 wd 3.2 quarts

this information is for 2.0L 4 cylinder engine code (C) DOHC
if you need information for 1.6L then send me a message back and I will give you the info.

check vaccum actuator on front diff?use vaccum gauge should be 25 to 30lbs to open had same problem 94 gmc sierra ext cabb 4x4 5.7 ordrive tranny

check the wires from the shifter for the transfer case they maybe discounected like mine were now mine works fine

shift into 4wd and move truck a couple of feet.
if light is still off, park truck block the wheels set the park brake jack right front wheel and try to hand spin the wheel if wheel doesn't turn 4x4 is functioning properly but there is a wiring problem use an ohmmeter to check the 4x4 switch wiring fuse and bulb
if wheel turns freely the front axle or transfer case is not engaged
attempt to hand spin the front driveshft if the driveshaft will spin the transfer case is not engaged check the transfer case shift linkage, problem is in linkage or transfer case internals
if the driveshaft will not spin the transfer case is engaged properly
with trnsmission in neutral or park start engine measure vacuum on the two vac lines at front axle shift motor . one line should have approx 20" vacuum. other line should have none
if no vacuum measured look for vac leak or bad vac switch
if both lines have vac look for a bad vac swithc or ruptured cad actuator diaphragm
if one line has 20" +- VAC
move transfer case lever to 2wd measure vac again lines should have swapped vac signals
if no vac switch bad or 4wd shift likage needs adjusting
if yes vac motor bad or stuck or shift fork stuck
remove vac shift motor from the axle attach vac lines to shift motor engage disengage 4wd
does shift motor plunger move at least 1/2 inch
no shift motor bad
yes check axle shift fork and vac motor for binging

1999 chevy 2500 ??? Come on a warranty , get real . Did you have the 4X4 system checked for DTC'S - diagnostic trouble code's ? Can set a few .
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

The range/mode switch circuit consists of four normally open switches. The automatic transfer case control module supplies a regulated 8 volt DC to the switch through circuit 431. The switch has circuit 1693 to return current to the automatic transfer case control module through a 9.09K ohms resistor located inside the switch.
The transfer case shift control module constantly monitors this signal voltage to determine the condition of the mode switch circuit. If no buttons are pressed, and the transfer case shift control module detects a voltage level outside the possible range (approx.-0.5 to 1.0 volts) for longer than 5 minutes, the transfer case shift control module will set this DTC or if a button is held down or sticks for a period longer than 5 minutes.
When each of the switches is depressed they will complete a circuit through their own specific resistor. The transfer case shift control module continuously monitors the switch input to determine whether the 4HI, AUTO 4WD, 2HI, and 4LO button selections are made by the driver. Neutral may be obtained if the following conditions are met:
• The engine is running.
• The automatic transmission is in neutral (or the clutch pedal is depressed on a manual transmission application).
• The vehicle speed is below 3 MPH.
• The transfer case is in the 2HI mode.
Once these conditions have been met, pressing and holding both the 2HI and 4LO buttons for 10 seconds will shift the transfer case into neutral, turning on the red neutral indicator lamp.
If you are not familiar with these electronic systems ,I suggest you take your vehicle to a qualified repair center .

i had the same problem.. it is the vacuum switch on the transfer case. the switch is stuck open and supplying vacuum to the vacuum diaphram under the battery box. the switch is located on the upper side of the transfer case ( not the front differential) which is located driver side of the transmission. the switch cost me about $25.00. I replaced it myself. if you do your own mechanical work you can get it done just be patient.

1- STOP THE VEHICLE
2- MAKE SURE IS IN NEUTRAL POSITION
3- ACTIVATE 4WD (HIGH) MODE( MANUAL OR ELECTRONIC SWITCH SELECTOR
4- MOVE LEVER SHIFT TO ''D' DRIVE POSITION
IF THIS DOES NOT RESOLVE CHECK TRANSFER CASE SWITCH