rgp717

Sorry, but I lost track of the forum. Long story short, I replaced the front axle actuator and now my 4 wheel drive is working. Thanks to everyone for all the advice. It's so much nicer to have my 4x4 back. By the way, removing the old actuator was a nightmare. I finally gave up and went to a garage, and they had to bust it into pieces before getting it out.

OK, Did the experiment. Put the truck in 4HI. The light on the dash board selector blinked in 4HI and then went solid in 4HI. Drove it about 50 feet into my driveway. Put the transmission in Park. Left the motor running. Raised the driver front wheel. Crawled under the trunk. I was unable to turn the front drive shaft by hand. However, I can spin the driver front wheel while its up in the air. So I take that to mean the front transfer case looks ok. My next experiment will be to remove the front actuator, reconnect its electric, and have my wife switch it back and forth between 4HI and 2HI, to see if the actuator moves in and out. So, I"ll report back soon. Comments welcome, especially if I'm doing something wrong.

Rats. Did not try to spin the wheel. I"ll do the experiment again and report back.

OK. Finally got a nice day and I got off my lazy butt. Put the Silverado in 4HI, drove it 50 ft into my driveway. Put it into Park and chocked the wheels. Lifted the driver side tire up and off the ground. Crawled underneath and could NOT turn the front driveshaft. So, next I need to remove the front actuator and see if it works or not. I'll post when I do that.

Davester, I was getting ready to try your experiments. But I have a question. So, I will start the car, press the button for 4HI and then I'll put the transmission in Drive to move it forward a bit. Do I put the transmission in Park or Neutral or what when I lift the front wheel to do your tests? rgp717

Each of those steps makes sense. Currently I believe my front axle actuator is bad (even though it makes noise when I engage 4HI). However, as soon as this bad weather clears, I'm going to try your suggestions. Thank you. I'll post back one way or the other.

So, I read on another forum of a way to test the front axle actuator. Chock the back wheels, put the car in Run (don't start it), put transmission in Neutral, put on 4HI, raise the front tires (both) off the ground, and spin the passenger tire by hand. If the driver tire spins in the opposite direction, then actuator is OK. If not, then replace actuator. I tried this test, and my driver side did not spin. So, that means I need a new front axle actuator. Has anyone ever heard of this test before? Do I really need a new front axle actuator?

A bit late but it seems like the right place to put it. I have a 2001 Silverado, 5.3 motor, Z71 with 4 wheel drive. Which does not work. I replaced the dashboard switch 2 years ago. Typically, I'm in 2Hi. If I press the 4Hi button, if flashed and then goes solid. I can hear the transfer-case-actuator making noise. I can also hear the front axle actuator making noise. But I don't believe it is in 4 wheel drive (no binding when making tight turns on dry pavement). I was hoping it was a bad ground to the front axle actuator but it makes noise (I put the key on but did not start the engine; put the car in 2Hi successfully; removed the electric connector from the front axle actuator; pressed the switch for 4Hi; the 4Hi switch blinks but does not go solid; crawled under the car and connected the front axle actuator and it made noise; and the dashboard switch goes to solid 4Hi. But no 4 wheel drive. One last thing:Put the truck in run (but did not start); pressed the brake and put transmission in Neutral. I simultaneously pressed the 2Hi and 4Lo buttons and held the press for 10 seconds. The dashboard 4 wheel drive switch does go to Neutral and the truck will roll freely. Put it back into 2Hi successfully. I don't recall hearing any grinding noise last year so I'm hoping my transfer case is ok. My next thing to try is removing the front axle actuator and cleaning it up. However, I am open to suggestions. Please.