4wd won't engage, 2000 silverado

the 4wd in my 2000 Silverado 1500 will not engage. It’s the manual stick on the floor to go from 2wd to 4wd. stick shifts fine and it goes into 4wd and the 4wd light shows up on the cluster. I had my buddy put it into 4wd yesterday with me under the truck and I can hear the actuator motor, it sounds like a servo. however the 4wd does not engage. the front driveshaft spins when it’s put into 4wd and it doesn’t make any bad sounds it just doesn’t work. i’m thinking maybe a bad/weak actuator. Any suggestions from anyone with experience on this? Thanks

might be the hubs not locking up. they should automatically lock up when you engage the tcase

how do I check that?

The hubs don’t lock on that truck. You need to get the front tires off the ground and remove the front driveshaft and actuator from the front diff. Then take a large punch (preferably a brass drift and make sure that the selector fork in the diff moves over. I should move about 3/8". Once you have moved the fork over spin the front yoke by hand and the axle shafts should both turn. In your case I would pull the tires since they are oversized and probably fairly heavy. Hope that helps.

Also the actuators really suck in those trucks and they are proned to failure. You can remove it from the diff then plug it back in and have somebody hit the switch to verify that it does infact work.

why do I need to remove the driveshaft to do this?

I heard you have to remove the entire transfer case to do that.

The actuator is weak and not pushing the shift fork in the front differential…REPLACE THE ACTUATOR…Bill

Advance has one in stock for a bit less than I expected it to be so i’ll go give it a try

I like to remove the driveshaft from the yoke on the front diff so I can spin the yoke by hand and feel what the backlash is like. It’s personal preference, but like I said in your other thread weeks ago it needs an actuator. The front diffs in 1/2 ton GMs really are craptastic and very proned to failure at higher milage intervals. I work at a dealership and it looks bad if I sell a customer an actuator in November and then something fails internally halfway through the winter. So I tend to air on the side of caution and check the units out probably a little more then need be.

I hope your making some kind of retarded joke like normal. Otherwise you really are brain dead.

Doe s the 4wd light come on or no ? Also is it electric actuated or manual ? As in do u have a 4 wd shift lever or a switch

read first post.

manual stick on the floor

the 4wd light shows up on the cluster

This era of 4wd engagement by gm blows. Some were full electric, then you get assinine crap like my jimmy that has the electric tcase servo with a vacuum activated front diff. All fail for numerous reasons. At least the dmax/ allison setup has part of it right…

Gotta do what will said and pull the servo off the diff and see if the servo is seized as well as check the diff fork/sleeve as well because many times the servo burns up because the diff lockup mechanism is bad

Well I put a new actuator in tonight and no luck, plugged the old one back in and it goes in and out like it should (with it outside of the diff). If I stick a screwdriver into the actuator slot I can move the pin in a little bit like I would assume I should be able to. Really stumped here. I would think if it was anything bad in the diff it would make a rough/bad noise but it doesn’t make any noise…

Its gotta move 3/8-1/2" or the sleeve doesnt engage.

Also try moving the fork while rotating the front prop shaft(front wheels off the ground, tcase in 2wd. If the dog teeth in the diff are right across from each other it can be difficult to fully slide the fork without moving the prop shaft a bit

Not to be a dick, but had you done what I suggested initially you would be way better off. You need to follow the procedure Adam and I outlined to figure out what your issue is. Did you try moving the truck forward a little to see if it locks in?

I don’t have jack stands large enough to get the beast off the ground. I can’t put it in the air until Saturday so I figured i’d try to quick/easy/cheap fix first to see if that would work. 10 minutes lost, no big deal

If the light is lighting up etc all the servos are engaging ! Need to see if driveshaft turns . If shaft turns and light is lit up he prolly has a issue in the diff

i have the same style 4wd in my 97. just a lesson i learned the hard way, put it in 4wd BEFORE you get stuck. Once you’re stuck sometimes it wont engage the front diff without rotating the front wheels.

also in the first post lol, it turns

it won’t work sitting in the driveway/going down the road so getting stuck and then trying it is not my problem lol

it’s gotta be a problem in the diff, I just have this mindset that if it’s in the diff it should be making some kind of bad sound. Am I so wrong to think that?