When my 2006 GS 300 sits out in the sun and gets hot, there is a very distinctive rattle that comes from the trunk area. Last summer this happened, and I just lubed the latch mechanism with some white lithium grease, but now it's back and lube does nothing.

Any ideas, CL nation?

 

Sounds like the heat may be causing something to expand..

Tighten the bolts back there and check the trunk struts.

 

Maybe your jack/spare tire/ hardware etc is loose. I would check to see if they are secured. Then I would look for loose coins in the inside body panels.