Can anyone give me some ideas on fixing these cracks in my car's trunk floor? I'm aiming to get a good seal so it won't leak and for it too not crack again once I put my sub back in. Oh and I'm trying to spend as little money as possible so I could use some cheap ideas. I appreciate any input.

Goes past the deadening to where my finger is..

And then there's this..

JB weld? lol Best option would be some welding or something. How the hell did that happen?

JB weld? lol Best option would be some welding or something. How the hell did that happen?

x2, JB weld sounds like it would fit the bill and would be the easiest route.

I would sandwich two pieces of 24 gauge around the crack. One piece from the inside of the trunk and another from the outside. I would smear silicone on both pieces first. This will prevent vibration issues and it will prevent water from coming into the trunk. I would then use aluminum rivets around the edge of the sandwiched pieces.

If you have a welder then welding is an option as well. If you hold a copper plate on the bottom side of the welded area it will help with blow thu. Or you will need to almost tack weld the entire length of it to prevent blow through.

Sometimes the easiest route isn't always the best. How did this happen? JB weld may not hold up to vibrations if that is the route cause of this.

I will add that I just had a metal brace behind my headliner crack. I silicone it last night to prevent vibration noises. I am anxious to see if that was a good fix in this case.

For a fix that will last I think welding would be the best.

grind the surface down with a 80 grit flapper disc..stitch it back together with a welder, coat with por 15, seam sealer from upol, done

May wanna drill some holes at the ends of the crack, so it stops its from spreading. Then do as above (welding)

If you don't have access and are going to use jb weld or sandwich the metal with other panels and silicone, I would definitely recommend drilling holes at the ends of the crack.

Thanks for all the suggestions.

All fixed.

So what caused it? And what method did you go about fixing it?