Using the top bunk for storage?

Do it! is this your truck? I pulled mine out completely and replaced it with a U-shaped shelf.

Remember if you panic brake and don't have stuff up there secured it's coming right for your head. Use lots of straps, etc. I would not be comfortable putting a fridge or microwave up there like some do.

 

Take the mattress off the top bunk and use it on top of the bottom mattress. Much more cushy. Then you have the hard base of the top bunk to put your stuff on. And just make sure you have everything strapped down.

 

I do that with mine. Basically i keep a thick wool blanket or tarp across the bottom after i removed the matress. Then its heavy stuff like canned goods in deep tall plastic tubs at the front up against the 3" lip for the matress closest to me. Light stuff like extra toothpaste, wet wipes small parts, dried noodles ect in plastic tubs at the back sized so all tubs are tight into the bunk area with the light stuff in the back against the back wall. Then throw laundry and spare blankets ontop both to muffle and help secure them. I keep my suitcase with various stuff in it turned sideways against the corner. Then you flip the wool blanket or tarp up over everything and Cut holes for the bedstrap latches then secure that with the bedstraps.

Basically the heavy stuff at the front makes sure the heavy stuff cant start slideing in a hard brake event. The tubs further wedge everything in and the blanket makes sure everything would need to move at once and helps if you have spills or whatever to clean up easier. The straps are just the final securement point.

I would need to roll my truck for it all to come loose.

 

Everything will move around. I had everything inside soft duffle bags, and each bag clipped to another bag by a carabiner. They were clipped, either directly or by connection with another bag, to some part of the truck so that with or without the sleeper net, nothing could fall from the bunk.

 

Many storage containers may not have good points you can use to secure them to the truck. Imagine stuff coming out of the containers and canned food flying forward in the truck. Modern windshields are paper thin and ELDs and phones can be damaged by flying cans.

Also, in a worst case scenario you may need to ride a Greyhound bus on short notice and have to get rid of anything you can't carry with you.

 

I got a couple of those 3 drawer plastic cabinet things. Screwed them down to purpose built "pallets". Strapped the palllets to the top bunk, after removing the matress. Used bungee cords to keep the drawers shut. Worked fine. Nothing moved, easy to access when needed. Safe, secure, handy.

 

I don't know, unless secured, one panic stop and all that stuff is on your head.

 

If the "panic stop" is violent enough to defeat the two inch ratchet straps holding them down, it's more than likely the stop involved a violent impact rather than brakes.
If you're referrring to the bungee cords holding the drawers shut, I had the cabinets on either side of the sleeper, with the drawers facing each other, not the front of the truck. No way braking would force them open.
But hey, it worked fine for me for years, your mileage may vary.