How to properly install Weatherstrip on Rear Tailgate

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

A

agaisin

10 Year 15 Year
Joined
May 12, 2010
Threads
74
Messages
1,106
Location
Northern Virginia
I need to replace the weatherstrip on the rear tailgate of an '05 lx470 (the weatherstripping that goes all the way around the rear opening - not the upper/lower door weatherstripping, but the body's weatherstripping). I've already got the replacement piece - my question is how is it supposed to be installed? Am I supposed to use 3M Super Black WeatherStrip Adhesive (or equivalent), or does it just go on without any adhesive (it appears to be the push-on weatherstripping)? Also, where do I apply the adhesive - just on one side (facing outside of car) of the flange, just on one side of the weatherstrip, on both the flange and weatherstrip, in the channel of the weatherstrip that fits over the flange, flange + both sides of weatherstrip + weatherstrip channel?

Apologize for all the questions but I'm new to this and already made the mistake of reapplying the weatherstrip with silicone RTV. Now I'm trigger shy and want to get it right.

I had leaking in the rear that wet the carpet. Step 1 I got the 3rd brake light replaced with OEM + aftermarket rubber gasket (apparently the OEM part has a crappy foam gasket). The leaking got way better but still had a leak from the weatherstripping that came in by the XM wire on the top of the weatherstripping and seeped down the side and into the rear (I did my own water test). I had read about people using silicone RTV and thought it was ok to use that to reattach the weatherstripping all around. Now I realize that's not the right way to attach weatherstripping - the classic weatherstrip adhesive never dries and can be cleaned more easily whereas the silicone dries permanently. I'm planning to use permatex silicone stripper to remove all the silicone and reinstall the weatherstripping the right way (it's bugging me that it's not on properly now).

Any advice on how to properly install the rear weatherstripping would be much appreciated.

Thanks!!
Art
 
IIRC, the factory applies mastic in a few spots, probablly to keep it from lifting. I've always replaced them without any additional mastic.
 
agaisin said:
I need to replace the weatherstrip on the rear tailgate of an '05 lx470 (the weatherstripping that goes all the way around the rear opening - not the upper/lower door weatherstripping, but the body's weatherstripping). I've already got the replacement piece - my question is how is it supposed to be installed? Am I supposed to use 3M Super Black WeatherStrip Adhesive (or equivalent), or does it just go on without any adhesive (it appears to be the push-on weatherstripping)? Also, where do I apply the adhesive - just on one side (facing outside of car) of the flange, just on one side of the weatherstrip, on both the flange and weatherstrip, in the channel of the weatherstrip that fits over the flange, flange + both sides of weatherstrip + weatherstrip channel?

Apologize for all the questions but I'm new to this and already made the mistake of reapplying the weatherstrip with silicone RTV. Now I'm trigger shy and want to get it right.

I had leaking in the rear that wet the carpet. Step 1 I got the 3rd brake light replaced with OEM + aftermarket rubber gasket (apparently the OEM part has a crappy foam gasket). The leaking got way better but still had a leak from the weatherstripping that came in by the XM wire on the top of the weatherstripping and seeped down the side and into the rear (I did my own water test). I had read about people using silicone RTV and thought it was ok to use that to reattach the weatherstripping all around. Now I realize that's not the right way to attach weatherstripping - the classic weatherstrip adhesive never dries and can be cleaned more easily whereas the silicone dries permanently. I'm planning to use permatex silicone stripper to remove all the silicone and reinstall the weatherstripping the right way (it's bugging me that it's not on properly now).

Any advice on how to properly install the rear weatherstripping would be much appreciated.

Thanks!!
Art
Click to expand...
@agaisin what did you end up doing as far as putting on the new weatherstrip. I'm pretty much in the same boat as you. Got the 3rd light sealed up, but still leaking. I've had the rear hatch weatherstrip all the way off and attempted to reinstall with the 3M weatherstrip adhesive, but still leaks and I can see the water coming down the outside of the weatherstrip up top then ending up on the inside of the weatherstrip on the bottom like a gutter funneling water into the channel beneath the body. Thank goodness the carpet is no longer getting wet, but I am determined to eliminate the water sloshing around turns after a heavy rain. I notice there are various clips and drainholes in this weatherstrip. Did you find a diagram that tells you how to orient the strip? I'm debating on buying a new one as I think it may just be an issue that it's on there wrong. There is no outright damage. The seal seems fine except it doesn't seem to pinch down on the pinch weld hard enough anymore to keep it sealed.

THanks,
Jason

Weatherstrip leak.webp
 
Last edited:
Detailx said:
@agaisin what did you end up doing as far as putting on the new weatherstrip. I'm pretty much in the same boat as you. Got the 3rd light sealed up, but still leaking. I've had the rear hatch weatherstrip all the way off and attempted to reinstall with the 3M weatherstrip adhesive, but still leaks and I can see the water coming down the outside of the weatherstrip up top then ending up on the inside of the weatherstrip on the bottom like a gutter funneling water into the channel beneath the body. Thank goodness the carpet is no longer getting wet, but I am determined to eliminate the water sloshing around turns after a heavy rain. I notice there are various clips and drainholes in this weatherstrip. Did you find a diagram that tells you how to orient the strip? I'm debating on buying a new one as I think it may just be an issue that it's on there wrong. There is no outright damage. The seal seems fine except it doesn't seem to pinch down on the pinch weld hard enough anymore to keep it sealed.

THanks,
Jason

View attachment 2035840
Click to expand...

This is exactly what's happening on mine as well, in the same pictured area. Planning on replacing the weatherstripping. Thanks for the replies and the instruction link by @Detailx
 
Where did you find the rear hatch weatherstripping. Mine is old and leaking. Do you have a part number ?
 
You must log in or register to reply here.

Share this page

Back
Top Bottom