4x4 issues........

[paxfam1]

Okay, 98 Chevy Blazer LS

I press the 4x4 high switch on the dash and it lights up, but my front wheels wont spin, so I put it in 4 low, same thing wheels dont spin in the front, but its is really geared down like its in low. When I push the buttons I can here something enageing underneath. I had been getting a clunk/pop for years while using the 4x4 but it never quit working. But now Winter in Mn and I cant get the thing out of my drive way cause I live on a icy hill.......................So where should I start?

[Blue Bowtie]

Start by searching recent posts abou the vacuum solenoid and actuator (under the battery). It sounds like the transfer case it doing it's job but the front axle is not locking.

[paxfam1]

ok, when I put the blazer into 4wd the drive shaft spins like its supposed to but the front differential is not enageing so.............Where do I start?

paxfam

[Blue Bowtie]

http://www.automotiveforums.com/vbul...d.php?t=648947

That should give you some clues.

[BlazerLT]

Do you have all the same tires on?

Have you only changed two recently?

[paxfam1]

All tires are the same and have equal wear....................onto looking at the vacume system I guess. Is there anyway to test the vacume switch or the agitator?????? I will pull them off and have a peak but not sure what to look for...

[lynndiwagon]

Here's the way I approached it:

1: Pull the battery and support. Underneath is the vacuum actuator for the front diff. Use jumper cables from battery to cables so you can start the vehicle.

2. Push the 4WD switch and observe the actuator. Does it move?

3. If not, give it a good inspection and apply vacuum directly to it and see if it moves. If it does than check to see if vacuum is getting to it from the hose by using your finger over the end of it. If it doesn't then it is probably bad.

4. If no vacuum then start tracing the lines back to the vacuum switch on top of the xfer case then to the source.

5. You will eventually find the problem.

Good luck.

Lynn Wagoner
Yukon, OK

[JaVeRo]

The vacuum actuator beneath the battery is nothing more that a steel plate and spring covered by a rubber diapham. If the rubber is torn, there is your problem. If not, follow Lynn's advice above.

James

[paxfam1]

Good News!!!!!! Removed battery and tray today and found that the vacume hose has fallen off the actuator so I popped it back on and it works!!!!! I am so happy. I couldnt have done it with out you guys...


Thanks again

[lynndiwagon]

Good Job!