Roof Leak from Shark Fin (Digital Radio Antenna)

SS502 · February 6, 2019

3 hours ago, silverado2k18 said:

my 2018 has the gap towards the back, with wifi. my buddy's 2018 has the gap towards the front, with wifi. same year.......

Of course! Sorry, MOST of the newer trucks have it in the front. It's not a water seal but for some reason GM started putting the gap towards the front. I plan on putting a sealant around the base of mine, hopefully it will stop water from getting to the seal inside that is SUPPOSED to keep the water out.

RACERX7775 · February 6, 2019

I guess GM designed the seal and said, we know this is gonna fail so lets design it so when water gets it, it can get out too? WTF? Id like to know the real reason why its designed like it is..

2003 SSEi · February 8, 2019

The Rubber with the gap, is not a seal. It is simply a way to attach the antenna to the roof, and have a good contour and not have any paint wear or direct contact from the plastic of the antenna to the roof.

As pointed out, you should not silicon the OUTER section of the antenna, as the gap is designed to let water/air out. The correct way is to remove the antenna, and use a silicon/RTV/whatever you want in addition to the foam seal.

here are some pics from my thread

I never had a leak in 90K miles as you can obviously see here. You can see the outer rubber of the antenna, and then the inner seal area.

This is the Foam seal that actually does all the work to keep the water out

The only reason I swapped was to go from the 14 Non painted Antenna on my Denali to the 15+ Painted antenna

g2full · February 8, 2019

Has anyone tried using stip caulk/dum dum/whatever everyone calls it? I think that's what I'm gonna try on mine when I take it off to "improve".

hamooz · February 25, 2019

Thank you y'all of your help.

My technician friend came last week and resealed the thing. We had to remove the headliner to have an access to the antenna.

I used "GE All Purpose Silicone - Clear" to reseal the stupid fin.

I hope the leak will stop permanently. However, I did lose my signal for the XM radio. It says "Receiption may be blocked".

My just re-activated the membership and tried to refresh the signal multiple times, but still no signal.

I'm not sure what is really the cause of the connection issue. We made sure every wire were properly re-connected. I suspect the antenna has been defective after the leaking occurred.

Shame on you GM! trying to save some money to build and install cheap parts leading to major issues.

RACERX7775 · February 25, 2019

Did it say it was blocked before you removed the antenna?

hamooz · February 26, 2019

23 hours ago, RACERX7775 said:

Did it say it was blocked before you removed the antenna?

No, XM radio was working before I removed it.

RACERX7775 · February 26, 2019

Well, either you blobbed to much on or you damaged the connector. Its gotta come apart again to see what happened. You didnt take the antenna apart did you? Its just the one bolt right? This is on my 14, i think the newer ones are a tad different because of the wifi..

hamooz · March 1, 2019

On 2/26/2019 at 9:36 AM, RACERX7775 said:

Well, either you blobbed to much on or you damaged the connector. Its gotta come apart again to see what happened. You didnt take the antenna apart did you? Its just the one bolt right? This is on my 14, i think the newer ones are a tad different because of the wifi..

That's what I think too. I might blobbed too much but I don't think I damaged the connector.

II just loosened the bolt that holds the antenna, I did not fully remove it.

I will just by another antenna and I hope that will fix the problem.

RACERX7775 · March 1, 2019

Why buy a new one. Take it off, peel the stuff off, reapply just enough to seal it.

hamooz · March 20, 2019

On 3/1/2019 at 11:57 AM, RACERX7775 said:

Why buy a new one. Take it off, peel the stuff off, reapply just enough to seal it.

We worked on it last weekend. We checked the wiring and try to remove the excessive rtv.

However, after several attempts, it still says "signal may be blocked" . I refreshed the signal multiple times through the XM website, but the antenna did not pick up any signal.

I ended up putting a new antenna. As soon as I connected it, "signal may be blocked" was disappeared . I finally got my XM radio working back after refreshing the signal with the new fin.

It costs me overall over $100 to fix the stupid leak and to restore the signal:

$10 for the clear RTV and the Caulking Gun

$50 for the new antenna (part # 23258394)

$50 for the labor cost that I paid for my technician friend

If I were going to the dealer to handle it, they would charge me nearly $300 to reseal it.

Edited March 20, 2019 by hamooz

RACERX7775 · March 20, 2019

Atleast its fixed now.

Ridgerunner30 · June 11, 2019

So it started raining inside the truck on Sunday. 2015 Silverado. I removed the shark fin antenna. Cleaned up the sealing surfaces and applied pure silicone sealant. We'll see how long this works. A hole in the roof is not a very bright idea.

HotRodDan · December 20, 2024

I have the same issue with my 2018 Equinox. Spare tire tub fills up with water when it rains hard. I've been wondering if my sunroof had been leaking cuz I had water in the back seat floor area as well. Could be more extensive than originally anticipated.

Not sure the reason or cause but I've noticed this came all of a sudden after I've been running my car through the automatic car wash. It's the one with the rotating flapping pads or strips. And those flaps beat on the sunroof and shark fin antenna. I may think twice about that particular type of brushless car wash once I finally get my leaking roof fixed.

swathdiver · December 20, 2024

4 hours ago, HotRodDan said:

I have the same issue with my 2018 Equinox. Spare tire tub fills up with water when it rains hard. I've been wondering if my sunroof had been leaking cuz I had water in the back seat floor area as well. Could be more extensive than originally anticipated.

Not sure the reason or cause but I've noticed this came all of a sudden after I've been running my car through the automatic car wash. It's the one with the rotating flapping pads or strips. And those flaps beat on the sunroof and shark fin antenna. I may think twice about that particular type of brushless car wash once I finally get my leaking roof fixed.

Put some clear RTV around the antenna and that should stop the leak. Continued use of those car washes will tear the RTV off.