So I parked my car and we had heavy rain throughout the night the next day I discovered THIS! The rear compartment was flooded (I highlighted the water level since it's hard to see). Has anybody experienced this???
I'm stumped as to where the water intrusion is, my trunk rubber seal is in excellent condition. Any thoughts would be greatly appreciated..Thanks in advance

Blue line is where water level is.

 

My guess is a leaky rear window.

Rick

 

Were you parked with the front of the car facing downhill to some degree?

 

Mine was caused by the rear glass, did a hose test and found it.

 

I know this may sound crazy but check your tail light, specifically the reverse light lens. If the lens is loose water will pool inside the light and spill into the trunk area. Happened to me and I figured it out on an accident.

 

Yes, somewhat but not really much of a decline.

 

1) You covered the weep hole! There is a drain hole in the bottom of that well, so if you get water in there - it drains out. You might want to get under the car, find it, and punch through your sound deadening. (That's what the hole is there for!)

2) Look for the TSB in Post #6. It has the GM procedure for walking through where all the water leaks might be on the car. https://ls1tech.com/forums/general-m...leak-rain.html

 

If it only leaks like this when the front is facing downhill, then water draining towards the back of the hatch channel is likely getting past the weather stripping near the corner. Some folks have seen this happen even if the weather stripping is still in fine looking shape.

Check out the link posted by wssix99 above for some ideas on further testing.

 

Yeah I did that, cut out the hole but I think there was a rubber plug there when I was applying the rattle trap I'll leave it open now.

 

Well my friend I think you are correct I tested the theory while washing the car, forcing water down the rear hatch I was on a flat level parking space and NO water intrusion Thank you

 

There was also a TSB for this sort of issue where GM missed sealing some body joints in the hatch gutters. You may want to see if that's your issue. If so, you might be able to go back to parking anywhere: https://ls1tech.com/forums/general-m...argo-area.html