even then the diaphragm moves the 4WD still does not engage

1998 CHEVROLET BLAZER

160,000 MILES • V6 • 4WD • AUTOMATIC

ISAACLEONARD15

MEMBER
1 POST

I tested the actuator under the battery and it goes in and out like it is supposed to which leads me to believe that is not the issue. I can hear the transfer case clicking so I think that part of the system is all good. However even then the diaphragm moves the 4WD still does not engage. Any ideas on what the issue could be? Is it the front differential switch? If you have any ideas any information would be great.

Dec 13, 2020 at 6:13 AM

KASEKENNY

✓Experienced Mechanic
18,907 POSTS

We need to do a couple things. First we need to lift the vehicle off all 4 wheels so the testing is easier. Then put it in 4WD and let off the brake and see if the front drive shaft is spinning. If it is not, then I suspect the encoder motor is the issue.

However, if the drive shaft is spinning then we do have an issue in the differential.

Let's do this first and then figure out next step because this is a fork in the road and depending on this we will know what to do next. Thanks

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Apr 25, 2021 at 4:25 AM

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