2004 2500HD blower fan started making rattling noise and was out of balance at higher speeds - vibrated badly. Removed fan assy and found whole walnuts in the cage! Cannot figure how they got there. No holes in cowl screens, nothing visible when using mirror and light up in the fan duct housing, etc.
A/C & heat work correctly, damper doors seem to move and seal correctly.

Any suggestions on what to look for or check?

Thanks.

Ken

 

Most likely rodents have been eating them there. Are there any shells or are they all whole nuts? Might have been storing them there for the winter. Seen the pests use the air cleaner for a food depot back in the day.

 

Appreciate the feedback. Mixture of shells and whole ones. Just can't figure how they got there. Don't drive the truck daily, maybe once per week, and there was not problem a week ago.

 

The cowl needs to drain water. The holes big enough for rodents.

 

either magic or mice!

 

Thanks for the info. Southern Indiana has been rained on for what seems months, maybe they decided to find a dry place!
Still just a strange occurrence - one day fine, a few days later, nuts in the blower!