Roof Leak

Lexington

Member
Recently I notice small leak in the back of my 4Runner. It seems to occur only in very heavy rain and it appears to be dripping from the top of the rear right pillar and dripping down below. The dirt blended so well with the interior color the only way I noticed it was when it ran down the black panel. My guess is it might be coming through one of the screw mounts that secures the roof rack. Wondering if anyone else’s has had a similar experience or have any ideas what would be causing it.

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[/IMG]Hi All
 
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Recently I notice small leak in the back of my 4Runner. It seems to occur only in very heavy rain and it appears to be dripping from the top of the rear right pillar and dripping down below. The dirt blended so well with the interior color the only way I noticed it was when it ran down the black panel. My guess is it might be coming through one of the screw mounts that secures the roof rack. Wondering if anyone else’s has had a similar experience or have any ideas what would be causing it.

The OEM sealing washers for the roof rack are a joke; they are paper thin. You have to replace them with something better. I used silicone caulk.
 
what was your process on sealing the mounting holes for your roof rack? it is likely the roof rack causing this leak

I don’t know. I had my roof repainted about 3 years ago so the body shop was the last one to put it on. I haven’t had any problems until now but this year we have had series of torrential rain that I haven’t seen here for a long time.
 
I don’t know. I had my roof repainted about 3 years ago so the body shop was the last one to put it on. I haven’t had any problems until now but this year we have had series of torrential rain that I haven’t seen here for a long time.

I would order 4 rubber insulator and washer sets for the roof rack and replace all 4 (not that expensive). there's something with how it's sealed from factory that keeps it tight and things get messed up when the factory bolts and seal are removed and replaced with something else or even replaced with the same rack. it doesn't happen for everyone but roof leaks post aftermarket rack install are not uncommon. you really have to be careful with how you reinstall.

I don't believe the factory rack is sealed with silicone so I don't think you need it. you can use it but I don't think you need it, the OEM parts should be all you need. the rubber insulator needs to sit properly as well, perhaps yours got moved

when you're done, best way to test is throw a bucket of water on the roof and see what happens. it can take a long time or you might not notice rain intrusion in a leaky roof. a nice bucket of water won't hide anything
 
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Thanks everyone.

I’ll take it back to the body shop that painted my roof and ask him to pull the headliner down to see what the mount holes look like. Hopefully there won’t be any rust. At minimum I’ll at least replace the seals. By any chance does anyone know what the part number is for these seals?

When I bought my 4Runner a few years ago there was a rust spot on top of the roof because the previous owner had used a magnetic antenna. I had him strip down the whole roof back then and repaint it. He showed me the rust spots then but there were only a few and none were in the mount areas.
 
Thanks everyone.

I’ll take it back to the body shop that painted my roof and ask him to pull the headliner down to see what the mount holes look like. Hopefully there won’t be any rust. At minimum I’ll at least replace the seals. By any chance does anyone know what the part number is for these seals?

I don't think the seals are available separately. They are very thin and practically worthless. For the TRD rack, there is a hardware kit that includes the seals; part number PT278-89190-HW.
 
I don't think the seals are available separately. They are very thin and practically worthless. For the TRD rack, there is a hardware kit that includes the seals; part number PT278-89190-HW.
I have a 2016 TRD and it’s just the standard rack.
 
Thanks everyone.

I’ll take it back to the body shop that painted my roof and ask him to pull the headliner down to see what the mount holes look like. Hopefully there won’t be any rust. At minimum I’ll at least replace the seals. By any chance does anyone know what the part number is for these seals?

When I bought my 4Runner a few years ago there was a rust spot on top of the roof because the previous owner had used a magnetic antenna. I had him strip down the whole roof back then and repaint it. He showed me the rust spots then but there were only a few and none were in the mount areas.

I think these are the seals but you can have your parts dept. check to be sure

front right: 6348635020
front left: 6348735020
rear right: 6348835020
rear left: 6348935020

you would need 8 washers

6343760020

and 8 bolts if you want to replace those, but yours should be ok. it might be easier to replace with new and reapply the red thread locker that's on them from factory. permatex threadlocker red should do it

9011908C47

The link fkheath posted I believe is for the TRD roof rack not the stock rails which I believe you have

unless you have other rust holes in your roof, water is coming through the mounting holes for the rail.
 
I think these are the seals but you can have your parts dept. check to be sure

front right: 6348635020
front left: 6348735020
rear right: 6348835020
rear left: 6348935020

you would need 8 washers

6343760020

and 8 bolts if you want to replace those, but yours should be ok. it might be easier to replace with new and reapply the red thread locker that's on them from factory. permatex threadlocker red should do it

9011908C47

The link fkheath posted I believe is for the TRD roof rack not the stock rails which I believe you have

unless you have other rust holes in your roof, water is coming through the mounting holes for the rail.

Thanks for this info! I was thinking about replacing washer, seals and the bolts. Having an old military vehicle I learned along time ago that I had less reoccurring problems whenever I replaced something by putting in all new seals, washer, nuts and bolts.
 
I think these are the seals but you can have your parts dept. check to be sure

front right: 6348635020
front left: 6348735020
rear right: 6348835020
rear left: 6348935020

you would need 8 washers

6343760020

and 8 bolts if you want to replace those, but yours should be ok. it might be easier to replace with new and reapply the red thread locker that's on them from factory. permatex threadlocker red should do it

9011908C47

The link fkheath posted I believe is for the TRD roof rack not the stock rails which I believe you have

unless you have other rust holes in your roof, water is coming through the mounting holes for the rail.
I think those are the wrong part number(s) for the seals. The seals go just above the mounting point on the car and are just washers. I believe this is the correct seal: 6343760020 Toyota 4Runner Roof. Rail. Seal. Luggage. Carrier - 6343760020 | Toyota Parts Direct, London ON

You are right, that is the mounting hardware for the TRD rack, but it mounts the same and at the same point as the roof rails. They both use the same seals which are just washers as noted above.
 
I think those are the wrong part number(s) for the seals. The seals go just above the mounting point on the car and are just washers. I believe this is the correct seal: 6343760020 Toyota 4Runner Roof. Rail. Seal. Luggage. Carrier - 6343760020 | Toyota Parts Direct, London ON

You are right, that is the mounting hardware for the TRD rack, but it mounts the same and at the same point as the roof rails. They both use the same seals which are just washers as noted above.

do you order from that london ON site? your location says utah, I'm surprised you linked to that site lol. there are washers but there's also rubber feet that I think go between the plastic mounts and the roof, like a big gasket. the washer go through the actual bolts. I think though, but am not 100% sure, I've never disassembled my rails, only watched youtube videos on it when deciding on a roof storage solution
 
do you order from that london ON site? your location says utah, I'm surprised you linked to that site lol. there are washers but there's also rubber feet that I think go between the plastic mounts and the roof, like a big gasket. the washer go through the actual bolts. I think though, but am not 100% sure, I've never disassembled my rails, only watched youtube videos on it when deciding on a roof storage solution

The only way water can get inside is through the holes for the mounting bolts. All the other parts are just cushions or transition pieces between the rails and the metal roof. Thus, the "foam washers", as Toyota calls them, are the key to keeping water out. Look at the instructions for the TRD rack (http://toyotaparts.sparkstoyota.com/install/PT278-89190inst.pdf) which mounts the same and you will see what I mean. (see figure 6-1 of the instructions.)

Since those foam washers are so thin and fragile, it is a good idea to augment them with something that seals better, such as a caulk. I used silicone because it does not shrink when it dries. It only takes a small amount around the bolt holes, not into the tread, to seal between the boss on the roof and the rack.

I linked that parts source only as an example of what they are and how much they cost. Do a Google search for that part number and you can choose the best place to buy.
 
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