Had a service the other day and afterwards I noticed a light grey materiel on the plastic intake manifold near the "chamber" (i.e. the empty box they add on to reduce intake noise). There were no notes on the service order so I zipped over to the dealer today to find out that is going on. The service writer says that a lot of the truck intake tubs develop small cracks and when they see them they just put the grey "caulking" on them to keep them from leaking. He says it usually tops them from cracking further. Being somewhat touchy about my beast I ordered a new intake tube ($190+install).

Obviously these cracks can be a problem since they are downstream of the air filter and airflow sensor.

Just thought I would pass this on as something to watch for. I did not get the feeling it is a hybrid specific problem.