2010 Mazda 3 Grand Touring - driver side floor boards front and back getting wet

Took my Mazda in because floorboards were soaking wet after it rained (it has done this off and on for a while). Dealership thought it might be clogged drain holes but found they were ok. After further inspection they said my rear tail lamp assemblies were leaking on both sides and both had to be replaced to fix the leaking. They want to charge me almost 1K to do this! Isn’t there a gasket or seal on the tail lamp assembly that can just be replaced? Or does the assemblies come as one unit? Is there something else that can be done?

I’m not familiar with the mounting system on this particular car but odds are there are some gaskets between the lamps and body. It’s a bit unusual for both to leak at a young age unless the car has been hit from behind or you live in an area with extreme heat or cold which has affected them.

Before coughing up a grand I’d see an independent shop and ask about having them sealed with some clear RTV sealant or something like that. RTV is 5 bucks a tube; add a little labor.

I’m also not familiar with how Mazda handles their parts situation, but in defense of the dealer it could be that simple gaskets may not be available to them even from Mazda and they have to purchase the gasket with the lamp as an assembly. This does drive the price up; a bunch.

The dealer is also less likely to use the clear RTV method as that would be a procedure that Mazda corporate might frown upon. Hope that helps.

I suggest you fold down the rear seats and take all the carpet out and watch from inside while someone is pouring water on the car’s trunk and see if the area around the tail lamps get wet. I had this happen in one car I had, as OK mentioned, mine was rear ended at some point and I fixed it with RTV.

Has this car been in a minor hit near taillights or somewhere else? Are you the original owner? I recall my Jetta was hit but nothing hard by a deer and it actually caused the tailight to longer seal properly leaking.

"It's a bit unusual for both to leak at a young age unless the car has been hit from behind"

“Has this car been in a minor hit near taillights or somewhere else? Are you the original owner?”

+1
Those were my exact thoughts.

Follow your owner’s manual for replacing the tail light bulbs to get access to the area. It might become obvious how to remove the tail light assembly to see what seal might have failed.

Doing a quick web search shows aftermarket replacement lenses are about $60 each for your car.

thingumajig wrote:
Isn’t there a gasket or seal on the tail lamp assembly that can just be replaced? Or does the assemblies come as one unit?

Many of the places that sell OEM parts on the Internet have the manufacturer’s parts diagrams. Questions like this can often be answered by looking at those diagrams.