2018 4runner odd sound primarily in reverse.

I have a 2018 4runner that I've been hunting to fix a sound since the day i got it . I did take it in under warranty numerous times but nothing was found accoring to the dealership. This is a sound that something just feels loose only at very slow speeds. Speed bumps and going in reverse down the driveway make this sound. The best way I can explain this sound, is if there was play in a bolt. It is a hollow sound, not a clank and not a bushing sound. It sounds as if something just simply isn't tight enough. I have king shocks and a icon delta joint, that I just greased up tonight and all of that is rock solid. This sound has been going on prior to the shock install. The suspension installation reduced this sound by a fair amount. This is what further stumps me because i thought it had somethign to do with the uca long bolt. But that's all solid now. I had it aligned a few months back, So I'm only assuming the lca bolt is tight, I could be wrong. Other than the uca bolt, which i could look at next, what are the other culprits? Thanks

 

Put a little grease on the hood latch and striker to see if it does the trick.

You can laugh at this suggestion, but only after you grease it.

 

Make sure the spare tire is up tight. The spare on my Tacoma makes a noise going over speed bumps.

 

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