I have been fighting with my 98 2500 4x4 for quite some time now. I lost 4 wheel drive about a month ago. I have narrowed it down to either the central axel disconect is bad or I have a vacuum leak somewhere. My question is, should there be gear oil in the cad vacuum motor? I pulled the vacuum lines off the vacuum motor and It was full of gear oil. Any info is appreciated. Thank you.

 

Erm, no. There shouldn't be. Think you just found your problem.

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