4x4 not working
 

I have a 1999 F-150 4x4, manual shift on the flywith 148,000 miles on it. When I put it in 4 wheel drive, the 4x4 dash light comes on and it sounds like it's engaging, but the front wheels don't do anything. I checked the 4x4 fuse under the hood and it's ok. A few months ago I had an alternator that was overcharging. It fried a new battery and the hi beam elements on the headlights. Could this have damaged something related to the 4x4 operation? Thanks.


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