A common issue with the YJ is a failure in the automatic vacuum system that locks and unlocks the hubs when going in and out of 4 wheel drive. I recently suffered the issue myself, so I thought I would share the experience so that others can refer to this to help with their troubleshooting.
To make a long story short, when I disengaged 4 wheel recenty, the dash indicator on the dash did not go out. I was several miles from home and I was concerned about driving it any distance with the 4 wheel engaged.
I moved into a paved area and turned the jeep in sharp circles. Had it been in 4 wheel drive my tires on the front would have chirped on the pavement due to there not being any slippage. Luckily, they did not chirp, so I thought I had a failure in the dash indicator.
On the drive home, I noticed the jeep would not get up to power and I knew that I had an issue. Fortunately, I made it to the house without any issues, and I put the jeep to bed for the night.
OK. There is a problem with my 4 wheel drive, so where do I start? Well, I started right here at wranglerforum.com. I read through several thread where particular YJ 4 wheel problems were discussed. There was plenty of information, so it got me on track for some troubleshooting.
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