Hey all! We have a 2015 extended cab Silverado double cab 1500 Lt with about 68,XXX on the odometer. The headliner stain tells me that the high mount brake light is leaking. I’ve seen several videos the show using a silicone caulk/sealant to solve the problem and have also seen quite a bit about using aftermarket replacement gaskets. The silicone method seems like it would work, until you need to change a bulb. Since the gaskets I’ve seen have adhesive on both sides it would seem that the same problem exists. Any advice is certainly appreciated! Thanks in advance.
High mount brake light leaking
- Thread starter PW01
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ls1mike
$50 Site Donor 2024
I just used the silicone on my truck. You can get the lens off if you need to.
I have a 2012 Ram and they are known for this issue. I replaced the OEM light with an LED version and siliconed the new one in place. Been 2 years and no issues.
Just my $0.02
What if you buy a piece of rubber sheet and cut your own gasket? However, if you don't want adhesive on a side of a pre-made gasket, it would probably come off with goo-gone or gasoline/diesel/etc petroleum solvent, or just spread a little silicone grease on one side to defeat adhesion.
Looks like silicone is the way to go
I’ve had a few leaks with cab lights. Silicone was tried but it interacted with the rotting rubber gaskets and never held. i then tried a tar-based sealant, which did better but cracked under the high heat. Black RTV has held the best.
I tape it all off first, lay the caulk or RTV, then quickly pull the tape up. Good, clean lines.
I tape it all off first, lay the caulk or RTV, then quickly pull the tape up. Good, clean lines.
What type of silicone? Silicone grease won't. Non-acid-cure silicone, aka sensor-safe RTV shouldn't either. You just don't want acid cure silicone caulking.
This will. I used it as a “temporary” fix for a leaking back glass seal. Probably waited too long to make the permanent repair as when I did it needed sanded and repainted.
Maybe less of a reaction and more trapping in moisture that was already present? Either way, that was my experience. So I prefer to use a properly sized butyl rope seal as a repair for with a back glass or vehicles with HMSL leaks.
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^ Yeah, that's "Acetoxy" (acetic acid cure) silicone. Safest to only use an RTV specifically stated as sensor-safe if it doesn't mention active ingredients or that it's neutral cure.
Where did you get the gasket?
Pick thickness needed
Use an x-acto knife to cut your own.
Have material left over for other gaskets.
Ram dealer.
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The one on my 2010 F-150 was leaking. I got an aftermarket replacement from Amazon for about 50 bucks. I've got body shop to install it for 25 bucks and it was well worth not to worry with the hassle since I just had shoulder surgery.