Liquid nail a few strips of mdf to the wall and rivnut them to hold your amps in.

 

Thanks. How reliable is liquid nails at holding up? I wouldn't want my amps to all of a sudden drop to the floor.

 

I used pl premium in my Silverado. I would recommend it over liquid nails.

 

Oh and some kind of solid wood instead of MDF. I used fir, nice n hard and weathers fairly well.

 

I Liquid Nailed 4 1x2 pine firing strips to my backwall and screwed a 1/2 MDF Amp rack to it. Very solid!

 

Have someone weld you a metal frame, then use the frame to hold the wood.

You can also use elevator bolts that have been JB Welded to the wall. Then bolt a board to them (recommend using hollow metal dowels in the hole to better distribute weight if you can find them). Hard to align the bolts on the wall to the holes in your board, though.

 

I welded up a metal frame then attached a sheet of mdf to it. Didn't have to drill any hole through body I used the seat belt bolts to hold frame in place

 

Been using butyl rope the last couple of weeks on something and it's holding fast. Same stuff that holds your windshield in.

 

I use Pl premium at work all the time as a finishing carpenter and think it would work fine. I used epoxy though because I take sick satisfaction in overdoing everything. I used some solid oak flooring about 5/16 thick and G2 epoxy I had left over from a canoe project. They fit well after a proper chamfer inside vertical recesses on the back wall of my superduty. I then used more of the flooring, installed horizontally, with 1 1/2" 10-32 studs epoxied in place. Everything painted gloss black. It holds two amps and an inverter.

I'd say epoxy is the safest bet, but Pl premium will stick to anything. I would never use mdf for a tensile load like that. Plywood with some form of condensation resistance at a minimum.

Good luck!

 

100% silicone caulk from lowe's or home depot works very well,have used this method for 2+ decades. if you have room do whole back wall (so you can kill any resonance too, two birds ,one stone do it.

 

I built a frame for my amp rack;

...then attached it to the back wall using elevator bolts and JB Weld. I used the cardboard to align three bolts on each side and hold it in place while the JB Weld dried.

I also used two small metal straps that I screwed into the inner portion of the back wall. (Not exposed to the elements outside.)

You can see more in my build log here: http://www.diymobileaudio.com/forum.../build-logs-project-install-gallery/162172-2014-silverado-crew-cab-z71-ltz.html

Hope this helps.

 

If it is like my old F150 or my present truck, the top of the rear wall right below the window is double layered... I extended a board flush with this section down to the floor, to function as an amp rack on my last truck. For a way to properly anchor to the metal (not a penetration to the outside of the truck mind you, just to an internal part), try drilling the hole and coating the bare metal with 2 coats of rustoleum rust convertor paint, then installing rivnuts into the holes and placing one more coat of paint... this should prevent any sort of corrosion for years to come.

A quick google search found this writeup... should work for you as well: Amp install behind DC rear seats - TundraTalk.net - Toyota Tundra Discussion Forum

 

If there are any close-by metal braces that aren't open to the outside of the truck on the back side, they're a good possibility for rivnuts. 4-6 rivnuts and you can hang amps on a board all day long. So if there's sheet metal to fasten with space behind that's all inside the truck, it's fair game.