Metal bed starting to rust, what to use to protect it?

[BLACK DEATH]

My 99 club car DS has a non dumping metal bed that's starting to rust on certain parts.
I don't mean just surface rust, but pieces are starting to fall off.
It needs some repair but after I fix the bad spots, what to use to protect it for longevity?
I don't think paint will last, would bed line be the best? If so which brand?
Anything to buy that works & to save money on?
Also I'd need to cover all sides so the rust will not return.

Or should I just buy an aluminum one and mount it up & be done?
My top does mount onto the current dump bed.

[LVCJ]

Here are 2 products I've used and they are good. Not to expensive.

[BLACK DEATH]

How strong or durable is that undercoating?

[LVCJ]

The undercoating is nice. You can layer it with additional coats to give it more thickness. Its pretty tough for spray can stuff.
I've also used a bedliner product that I rolled on called Herculiner. Its stout.

As with any product, prep is the key.

[55BigBlock]

I use a product called POR 15. I have used it on many old car projects. Apply as directed and paint over it because it is not UV protected.

http://www.por15.com/Rust-Preventive-Coating_c_11.html

[ckiguy]

i work at a major fleet of trucks and trailers, we use gray primer on the bare metal, and Rustoleum....

[BLACK DEATH]

I'm going to repair the damage, fix the hinge for the gate.
Then grind or sand it all down, use ospho rust treatment to stop any rust.
I just can't decide on coating inside or outside for longevity.

[Seafarer12]

Your on the coast. You could always go to a boat place and get you some good 2 part epoxy paint and primer. That is what we always use to do when I worked on ships. Ospho, prime and paint. It would last a couple of years in the middle of the ocean.

[BLACK DEATH]

I wonder if bed liner will last longer if I do the entire box?
Or just buy a darn aluminum one & be done