JVERMETTE

2020 GMC Sierra 1500 Denali: In the shop for paint imperfections on the bed. Also, they have resealed and fixed the spoiler, now I have water again in the back behind the seat. The pulled out the back seat and found water coming in through the black plastic vent that is in the middle of the back wall of the cab. They ordered another one and replaced it and put extra clear silicone around it to seal it up.

Everything was stock on my truck with the 5.3L V8, no extra option.

Yes, at 17000 miles I noticed a leak under the line on the liner. Took it to the dealer. They replaced under warranty stating the o ring inside the line from where the line goes from metal to rubber was leaking oil out slowly. Caused by the pressure that builds in the line. Currently have 38000 no other issues with the truck. Not even the shaking issue.