Taking on rain water when parked downhill

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


Feb 25, 2015

So I parked my newly purchased 80 series (love it!) pointing downhill and left her there for a few days.


We had some heavy rain. Next time I drove away I could hear water sloshing around down to my left.

I stopped and saw what must have been several gallons of water leaking out here:


This happened again, also when parked downhill. Since then I've been parking her uphill and haven't had any issues...

Another thing I notice is that there are other holes like the one the water is leaking from along the sill, but they all have rubber plugs in them. Should the one at the back have one too?


Any ideas please? How should I start troubleshooting?

Possibly a plugged sunroof drain? I've never had the issue, but I've read that you can use stiff weed eater line to clean the drains out from the topside.
While your at it, another place you might want to check for water leaks, that is after you fix the sun roof drains, is under the rear sliding windows. While hooking up my trailer lights i found signs of water leaking in to my truck from some small plastic tabs that hold the rubber window molding in place. It seems that these tabs are a common source of water leaks due to the age of our molding.
Check that your windshield isn't leaking as well. You can sometime see pooling on the gasket corner depending on where the water is getting past.
All the water from the front two drain tubes dumps directly into the rocker panels by design (normal). The rocker panels have four slit drains at the seam found along the bottom of each panel for the water to drain out however water can get trapped in the panel cavities if those slit drains become plugged. Do a search for sunroof+drains+rocker+panels+zip+ties.
While you should check all of the aforementioned places regardless, I can almost guarantee you it's your rear hatch seal. If there's even the slightest tear in the wrong spot you'll get a lot of water in the cab. It'll run under the carpet and all the way up to the front kick panels. I had the same symptoms: parked nose up in driveway, no leaks. Parked nose down, water galore. Replaced the rear hatch seal with new OEM and silicone sealer behind it and no more leaks. New seal ~$70 IIRC.
It's the slit drains in the rocker panels. If rain doesn't come in around your sunroof, it's probably siliconed shut. If the water is making it to your rocker panels, your sunroof front drains are operating as designed.

If you pull those little plastic plugs, you might be okay, but don't go through any mud or things will get a whole lot worse. Best thing is to clean them out and flush out all the crap through the slits.
I have just finished reading all the links here pertaining to water in the front passenger footwell, and have actually found and fixed some of the issues mentioned.
I still have some water in the footwell, next to the kick panel only now, whereas I used to have a couple of inches sloshing around the entire right front.
Background: I have a 94, and initially noticed the problem about three years ago. I was parked nose down, and it rained for about two days, lots of heavy, only-in-Missouri kind of rain. Afterwards, you could have grown cranberries in there. At the time, the vehicle was stock, with no sign of previous leaks. The windshield had been replaced due to hail, and the sunrook is/was cracked, but outer layer of glass only. I simply figured that the torrential downpour had overwhelmed the front sunroof tub drain, dried everything out and forgot about it.
Fast-forward a year or so: a snorkel was installed, it's been very dirty, with Clayton OK mud accumulated in the underbody areas, and it's several years older and parked outside, driven once or twice a week at best.
I got tired of the leak, and got busy one day, pulling as much junk out of the right side of the dash as I could in about 30 minutes. I then opened the sunroof and poured about 12 ounces of water down the drain at the right front, and watched it shower all over the inside of the dash. Hmmm, I thought I had a problem. Briefly, I accessed the drain tube and found cut marks from the snorkel installer's drill. Bingo, thinks me. A new tube from the dealer (not necessary, and hardware store plastic tube would work) and I poured more water down there. Oops, there's a couple of holes in the tub itself, under the track mounts. Black RTV fixed that, now I'm thinking I'm golden: water all runs out the opened drain plug hole in the rocker, and the slit drains after the plug is re-installed. I re-stretched the headliner back into place, cleaned up and patted myself on the back. That was about three months ago.
Today, and the last few days in the DFW area, it's raining like almost never before, and you'll never guess: I have water in the very outside edge of the footwell. Still. Thinking I maybe had a clogged drain, or a problem further back, I started pulling door sill pieces and looking for water and found nothing in the front or rear doors at all, dry as a bone. I then looked to see if I had jammed some Oklahoma vegetation in the windshield seal, clean as a whistle. I even opened the sunroof and looked for puddled water in the tub. Nada. So as I got wetter (it's still raining and I'm now out of work shirts) I noticed a blob of black RTV in the right front rain channel, about two inches up from the bottom and pretty much hidden by the snorkel, don't know if it's from the windshield replacement or not but I'm thinking it is, that was causing all the water running down the rain channel to be directed into the slight gap between the base of the A-pillar and the very top of the front fender. I'm thinking I maybe need to pull the cowl cover and get a look in there to see if its drain may be plugged with dead leaves, rat dwellings or carcasses, cockroaches, whatever, or just look and see if there's any way water to get inside the vehicle from the inner cowl. I'm thinking there may be.....
And thanks for reading this rather wordy tome, I work in a wine storage warehouse that's kept at 56 degrees and am NOT going back there until I dry out, so all I had to do was write this.
... ... is, that was causing all the water running down the rain channel to be directed into the slight gap between the base of the A-pillar and the very top of the front fender. I'm thinking I maybe need to pull the cowl cover and get a look in there to see if its drain may be plugged with dead leaves, rat dwellings or carcasses, cockroaches, whatever, or just look and see if there's any way water to get inside the vehicle from the inner cowl. I'm thinking there may be.....
And thanks for reading this rather wordy tome, I work in a wine storage warehouse that's kept at 56 degrees and am NOT going back there until I dry out, so all I had to do was write this.
I was sort of having the same problem last year and I took a hose and blasted the crap out of that portion of the fender/cowl and cleaned an awful lot of muck from between the door/fender/cowl area and now everything drains out as designed.

At least I think it does, I'm in California and it may never rain again here so I may never really find out.

Well, at least I'm not chasing windmills. I plan on poking around some more this weekend, I'll probably find a potato farm in there.
Rusco - I have a 94 as well. You mentioned that you messed with the headliner. I believe that I have a drain tube that's come loose from the DS front sunroof drain. Do you know if that headliner under the drain could be peeled back just enough so that I could get at that freakin drain hose? I'm not too excited about messing with that headliner for fear of it not going back correctly? Thanks
Alleycat- I had the same misgivings, but decided I really needed to change the tube so I went ahead and dove in.
I was able to get to the drain tube at the tub easily enough: I removed the sun visor, A-pillar grab handle and the door frame and sunroof opening welting, then gently pulled the headliner away by peeling it off the various lips and away from the edges. It's secured with a glue similar to rubber cement, so it goes back without having to re-glue it. The fabric is flexible enough to allow you to gently move it away from your work area. Just try not to stretch it too much. After replacing the drain tube, I pulled and tweaked a bit to remove wrinkles as I secured it, then installed the visor, grab handle and trim. After a couple of days, you can't tell that I ever had it apart, aside from the fingerprints I left, which cleaned up with brake cleaner just fine. If I had thought to wash my hands first, it would have been smart on my part.
While you're there, it might pay to take a look at the hardware at the front of the sunroof tracks, since as I mentioned earlier, mine had some parts missing (if I recall correctly from my days in a Lexus dealer) that allowed water collecting in the corner of the tub to drain inside rather than to the outside through the tube. Rather than find out for sure if I was missing a couple of plastic plugs, I simply sealed the smallish square holes with RTV, then re-attached the caps at the front of the tracks. I should add here that you would have to have an absolute boat-load of water in the tub to have this happen, but I might be a little OCD.
But wait, there's more! Just on the off-chance you're replacing the tube, I took a lesson from my own past doing automotive electrical work: I disconnected the drain tube at the tub, taped the bottom of the new tube to the top of the old tube and pulled on the bottom of the old tube until the top of the new tube was in the proper location to connect to the tub drain fitting. It was then a simple matter to separate the two tubes, old and new, stuff the new tube's bottom into the rocker cavity and button up the trim.
Mission accomplished in 15 minutes thanks to the help of Rusco. Reached and re-attached forward DS sunroof drain hose drain quickly without even removing visor or A pillar grab handle. The part of the headliner that I pulled down went back up nicely. I have posted a couple photos for future generations who may have same issue.



Pull visible plugs when you get a "puddle" in that side floorboard replace / run the heater with A/C on to dehumidify fastest & without the floormat in 'till dry. Replace once you fix prob, or sooner if you lose things easy.

Snake sunroof drains with weed eater cord (plastic rod, thin) & it comes out where draining water pic shows - (6" behind FR wheels inside of rocker pinch weld flange for FR sunroof drains - if pic link breaks)

I park in shade under a tree & live in WA - I snake the drains every 2 yrs & drop an eye dropper of bleach after snaking to kill moss that builds on dust (overkill: maybe, but no visible paint hits bleach), prob because of the shade park & under tree.

Snaking every few yrs is norm for my climate & the amount of mud flung onto roof that drains to sunroof ports & blocks them.
Snaking/reaming/routing is good, no doubt. I've dealt with clogged/stinky tubes repeatedly as a dealer tech. I like the bleach idea though, mildew sux.
Keep in mind I have a new tube, the rockers drains are clear and the tube at the tube is clear.
I'll know more this weekend after I get the cowl cover off and take a peek in there.
Alleycat- Schweet!
Just because I did it once doesn't mean it worked, my lesson for the day. As threatened, I pulled the cowl cover, and not surprisingly once I thought about it, all the air intakes and such are on what is my driver's side. Makes sense if your primary market drives from the wrong side of the car. Anyway, I cleaned up the tomato patch under the cowl, old vegetables and mud, and poured water down the pass side rain channel, and watched all of it go straight to the ground. Schweet, one more thing that's not wrong. Back to the basics: I poured more water down the right front sunroof tub drain, and by gawd if I didn't have water dripping off the bottom of the far right of the dash, outside bottom of the speaker cover. So I pulled the headliner out of the way, pulled the speaker cover and glove box and poured some more water down the hole. Zippy do da, water. I should note here that this time, I noticed the thin foam backing on the headliner was damp. It was still coming through the screw holes for the track attachment in the tub, something I thought I had fixed. Did that again and had the really smart idea of closing the sunroof and pouring water on top of it, just for grins. It leaked pretty good, imagine my horror. So digging back into my mis-spent youth and shady past, I got to thinking again, why don't I try and adjust the dang sunroof?
Typically, in order to minimize wind noise, sunroof glass is adjusted to place the leading edge of the weatherstrip about 1.5 mm below the level of the roof, and nearly flush at the back. Mine was at least 2mm lower than that at front and back, all four corners.
Okay, one more thing to try. After about 20 minutes, should have been five but I couldn't find my stash of shims and had to use washers, my sunroof is about 1.5mm proud of the roof. I raised it that much for two reasons: 1) I could see where water was coming in and wanted to get a softer part of the weatherstrip working against the sealing surface on the roof, and 2) I wanted to eliminate the puddle of water that collects in the corners of the sunroof when it's adjusted to minimize wind noise, something I could truly care less about, even if I could hear it over all the other noise this thing makes at speed. I've got BFG KM2s on the thing, I can't hear the t-case whine over that, let alone a wind noise from the sunroof.
So: Re-check on me for not getting the screw-holes in the tub sealed the first time, and a "doh" for not thinking to adjust the glass so as to prevent a puddle forming where the water was coming in from.
Not supposed to rain here for at least another week, I may go to a car wash just to torment myself, and I haven't washed the pig in about a year, it could probably use it.
Last edited:

Users who are viewing this thread

Top Bottom