I was super disappointed when my new to me LX450 had a sunroof leak on day one.
Seals, drains, carpet, I feared the worst. I lost sleep, I dreamt of complete headliner removal and dropping $250 on a new sunroof.
I verified all (4) drains, and I even had to put the zip tie to the rockers, but it was certainly the seal. So here is my super cheap fix, and I hope that it saves someone some ca$h.
Step 1: remove the left and right garnish on the sunroof while sitting in the car. It will break, there is no way around it, just accept the fact the garnish covering the (6) 10mm nuts will break.
Step 2: remove the glass from the truck and take it in the house and set it on a table, with something soft under it. I used a rubber kid seat protector.
** note how easy the glass lifts out and goes back in. If it drops in and pops out with little to no effort that is a clear indication that the gasket has shrunk.
Step 3: clean the glass and assembly, I used pinesol and water, then I lubed, messaged, the gasket with this stuff. I had in in the garage.
Step 4: Jam this screen door rope (0.160) that you can get for $5 at the hardware store into the gasket seam and let it sit overnight, with plenty of the lube on the gasket.
** the sunroof will not fit back in the sunroof hole with this rubber rope in the gasket. The rope is too fat.
Step 5: make sure you clean the outside seam with lube and a smooth device, i used the smooth end of a 1/8" drill bit.
Step 6: remove the rubber rope and add paracord to the gasket seam and see if the sunroof will drop down into the sunroof hole. My sunroof was still too wide with the paracord in the gasket seam.
Step 7: if the stuffed gasket is still too fat to fit back in the truck, remove the center cord from the paracord and try again.
Step 8: you will see that with each fit attempt you can see where you need to trim out the paracord filler, I had to cut out most of the back side of the paracord for the glass to just bearly drop into the sunroof hole.
Step 9: once the panel will go back in and out of the sunroof "with help" you can see where adding meat to the gasket will really minimize the gap between the sheet metal and the glass gasket. So snug everything back up and then actuate the assembly after the bolts are tight.
Check for clearances, and don't force anything.
Step 10: go get some 3M silicone past at NAPA and lube all of the moving parts especially the two worm gears.
Notes: I Rain-X'd the glass while it was out.
The 3M silicone paste is the jam.
I like the VRF stuff works great on all kinds of car plastics, with no odor.
I accepted the fact that the LH and RH garnish would never be seen again.
I did add a shim at one location to get the gasket near flush to the roof.
Here is the link for the shimms
Sun roof shim part number