rear vents leaking in Duramax

kite2012 · Sep 20, 2024

I was wondering if any one has every replaced the rear cab vents/valves? Mine are shot and leaking water. There is standing water inside the tubes/ducts behind the back seat of my truck and getting water onto my carpet. I am hoping I will not have to remove the bed in order to do this.... Also, I am trying to find the exact name of them so I can order replacements for them. I've heard of people blocking them off but I don't want to lose their functionality.

TexasLife · Sep 21, 2024

although it's a gm product and not directly related to a duramax i haven't had any issues with a 23 year old p/u with those. what year is it? with it being a gm it might be something that only you can get thru gm and not a non-dealer parts supplier.

video might help

TackDriver284 · Sep 21, 2024

What a small world, I just did my vent replacements last week. I had the same issue, no need to remove the bed, the Chevrolet body shop said they would need to remove the bed to fix it but its a bunch of BS, so I decided to do it myself, so I removed the rear seat to let the carpet and mat to air dry for two days with fans running and all doors open. Since the rear seat is out, pull the corner trims , not the top part, just the lower and middle parts and move it out of the way, and pull the rear mat from the rear panel, starting from the corner area, once you do, you will see the vents. Just get a wide blade screwdriver and a hammer and tap the top part of the vent where the clip is, and knock the vent out, clean both sides of the metal panel with a rag and alcohol. Have someone go under the truck, and put the new vent up in between the cab and bed, make sure vent flaps are pointing downwards, hook the lower clip over the bottom panel, and from the inside you can pull the top part of the vent inward until it snaps in place. Put a good ribbon of black silicone on the top inside vent where the clip is, it will help prevent leakage once the seals start to erode over time. Just reinstall everything back in place. The rear seat is a pain in the butt, a small crowbar or a large pry screwdriver will help raise the brackets over those bolts and centered to tighten them down. Here is my recent post.