Weird noise from front end once in a while

[94sportX]

Hi, for the past few months now while I'm driving all of a sudden there will be a weird noise coming from the front of my 94 explorer.
It will almost sound like when you put baseball cards in the spokes of your bicycle. If I come to a stop I'll hear a slight thud right before I stop and then it's back to normal.
This has only happened about 3 times in the last 3 months. It only does it sometimes for no apparent reason, and then will be fine for another month or so.

Anyone have ANY idea at all what this could be? I'm kind of scared to drive it since I have no clue what it is...I don't want to get stranded somewhere.

Thanks for any help at all, this forum is great!

 

[MrShorty]

Baseball card in bicycle spokes is often associated with problem with the auto hub. Do you still have the stock auto hubs? If so, I'd start there.

 

[94sportX]

Yes, I have the auto hubs. Is this a common problem? What exactly happens to them? I'm kinda new to 4x4s, so I dont know much.

Thanks for the help so far.

 

[MrShorty]

Yes it is a common problem on these. Not sure on all of the failure modes, but they either won't engage and leave you without 4WD, or they won't disengage and make all kinds of noises.
If you don't want to put any money into it, you might try taking the outer hub off and cleaning the excess grease off of the cam and out of the inside of the hub.