1990 K1500 4x4 Issue
 

I just purchased a 1990 K1500 350/5 speed. I found out today the 4wd is not working. So I did some research, I bought a new actuator, and installed it this afternoon. I can place the transfer case in 4hi or 4 lo, but the front axle will not engage. I have waited and gave the actuator time to work (it is a cold day here) and it will not work.

I unhooked the actuator and put a voltage tester on it and am getting 13volts to it when the transfer case lever is moved to 4hi/lo.


What else could the issue be?

Re: 1990 K1500 4x4 Issue
 

Where did you get the new actuator? Have you tested it to see if it works??

Re: 1990 K1500 4x4 Issue
 

I got it from Advance auto parts.

I checked the voltage at the connector and it had 12+ volts.

I left the actuator out and shifted the transfer case into 4hi. The actuator extended about a inch.

Re: 1990 K1500 4x4 Issue
 

Remove the actuator,
Manually push the shift fork in while turning the right front wheel,
The fork should move in about an inch and engage the front axle.

Let us know if you can push the fork in, or what happens.

Re: 1990 K1500 4x4 Issue
 

I pulled the actuator, jacked up the truck and had my wife slowly rotate the passenger side wheel.

I pushed in the fork, it did move. I could hear and feel a slight ratcheting sound/feel but that is all. No reaction from the other wheel.

Re: 1990 K1500 4x4 Issue
 

So when you did this, did the drivers side wheel, and the front drive shaft stay still?

Re: 1990 K1500 4x4 Issue
 

The driver side wheel did not move. I didn't look at the driveshaft.

Re: 1990 K1500 4x4 Issue
 

If you pushed the fork far enough, and the front axle did engage, and the drivers side did not turn, then the front drive shaft would have to turn, or there is a problem in the front axle.

Re: 1990 K1500 4x4 Issue
 

I tried it again. Turned the passenger side wheel. No movement from the driver side or the driveshaft.

Last night I was trying out the actuator and the had someone watch the driveshaft when I shifted it. It turned when it was in 4wd and stopped when it was placed into 2wd.

Re: 1990 K1500 4x4 Issue
 

It is time to look inside the front axle.

For me, if it does exactly what you say, I would remove the right axle housing assembly so I could inspect the fork and gears that mesh.

Here is a thread on the same topic, that ended up being the front drive shaft splines were stripped, but we covered other possibilities.
http://www.chevytalk.org/fusionbb/sh...fef7012246ac9/

Here is a thread from this site with a good photo of what happens if someone allows the front right shaft to move out while working on it, and then pounds it back in.
http://www.chevytalk.org/fusionbb/sh...st/1728137/hl/

Re: 1990 K1500 4x4 Issue
 

I took another look at it after reading the links you posted. I believe I have a issue to do with the cv axle.
This is my passenger side axle.

Re: 1990 K1500 4x4 Issue
 

When the axle moves out, like in your photo, the washer almost always falls down, and the right axle housing needs to come off.

Does the truck have a lift kit on it?

Are the torsion bars cranked up?

Did you do some front end work recently?

Re: 1990 K1500 4x4 Issue
 

I just bought the truck Monday. I am going thru it and trying to get it roadworthy and ready for winter.

It has no lift kit, nothing done to the torsion bars that I can tell.

Is the fix for this rather simple? Pulling it apart and correctly assembling or does the washer that falls out cause major damage? I'm likely going to have to take it to a mechanic because I don't feel comfortable tearing into it.

Re: 1990 K1500 4x4 Issue
 

Once the washer falls down, the axle will not go back in all the way unless it is forced, which destroys the washer. Usually you can't not get it into four wheel drive after the axle is forced back in.

The washer is between to parts that spin opposite directions when driving in two wheel drive. That washer has to be in place and in fair condition or there will be a grinding noise and metal shaving being produced when the truck is driven in two wheel drive.

To me it is an easy repair, but for many people it is beyond the scope of what they should attempt to repair.

Re: 1990 K1500 4x4 Issue
 

Where would I be able to find a how to on a fix for it?