Rear storage area behind the bumper

[Life is a Highway]

Came back in from a month on the road with our 2021 FC. While getting it cleaned up to go back into storage I opened the rear bumper locker. I removed all items then when I pulled out the the black rubber floor underneath I discovered a wet mess of rust and corrosion. I though I had removed all the filings Airstream left in it from the factory but I guess not.

I am letting it dry out while back inside storage and could use some suggestion on what you have done or not done to clean up the surface rust. What did you apply on the floor to help from future corrosion.

I was going to sand it clean wipe it down with solvent prep and use a rattle can of bed spray liner., What have you done other than put the mat back in and ignore it.

Thanks-

[waninae39]

yes scrub and spray sounds like a plan
drop pics pls afterwords

[Mollysdad]

I don't have a mat. Mine gets wet since it's not sealed, but hasn't rusted out. I may hit it with some spray anyway.

[Rich Jenkins]

I've removed the mat entirely. For me, I don't see the purpose, since I store things which do not matter if they get wet. And it removes weight from the rear. And it no longer traps moisture.

I remove everything and spray the exposed steel with an anti-corrosion spray. I forgot what product it was, picked it up at Harbor Freight I think.

I only store a few plastic lego blocks and the sewer hose back there, so YMMV.

[nelsonh]

I've recently acquired a 23' FC with the same bumper storage, and while it's handy for sure, I can't for the life of me figure out why there are no drain holes in this compartment from the factory?? The way it is, it's like it was designed to hold water! So I've been really wondering what the downside to drilling some holes in the bottom plate of the compartment would be? If I put some paint on the exposed drilled hole edges, wouldn't this be better than it sitting with water in it all the time like it is now? Tell me I'm wrong...!!

[Rich Jenkins]

Should be drain holes. I forget where mine are. Plus as the coach moves under tow, the water should skim out to the crevices or evaporate.

If you are seeing pooling while camped, it may be the factory forgot to drill any. Adding some more is a simple matter, any good steel bit and a drill and get to work. I'd treat any bare metal with anti-corrosion spray. I don't recall but I don't think the bumper storage base is painted...

[Silvr_Bullet]

Not available to look at, but isn’t the bottom of the bumper aluminum? I have a mat in mine to prevent scratching. I keep Lego blocks in mine.

[Alovlien]

Airstream putting a mat in that wet compartment is dumb. Once you get rid of the mat, drill some drain holes, prep and paint the metal. Then put in some dri-deck tiles that lift the stuff you put in the compartment (stuff that won’t degrade with moisture) off the floor and allows your stuff to dry out and have ventilation air movement.

[majorairhead]

The pan on mine is galvanized. Mine was rusted under the mat too. I removed the mat, prepped the pan, primed it with galvanized friendly primer, and painted it with oil based galvanized friendly paint. It turned out super nice actually!

And on mine, the weep holes were in the back of the pan along the rear, I made sure they were opened up good during the paint job

[Squirrel44]

Originally Posted by waninae39

yes scrub and spray sounds like a plan
drop pics pls afterwords

Punched a few extra drain holes with drill. Mat is sort of borderline, in theory it would stop rattles but in reality not super useful.

[Mollysdad]

Drain hose will let water splashing off the tires IN.
I look at mine and it's got lots of drainage. Look around the bumper, it's so open some people lose their awning rod out of there. Even the lid is not watertight.

[Life is a Highway]

Great suggestions
Thanks. That mat is going away. It caused the problems

[Rich Jenkins]

It's funny, out of the five we've had, the only one with rust to form under the mat of the rear bumper compartment was our 2022 23GT.

We bought it new at Colonial March 2022, and during one trip that summer, I was astonished to take out the mat and find rust forming on the steel underneath. I scrubbed it as best I could and applied some anti-rust spray all in, then replaced the mat (bad idea, from thinking about now). We sold that unit last year because: reasons, so I'm not sure what condition it's in now.

All our other Airstreams (2016 30FC, 2017 27FC, 2018 23FC and our current 2019 25FC we bought used in Feb) have had no issues in that area.

[Sailorjamie]

I lined the bottom of my compartment with Dri-Dek https://www.dri-dek.com/
It solved the problem. It exceeded my expectations in terms of drying out the compartment. I'll try to snap a picture sometime soon.

[PA BAMBI II]

Originally Posted by Rich Jenkins

I remove everything and spray the exposed steel with an anti-corrosion spray. I forgot what product it was, picked it up at Harbor Freight I think.

I only store a few plastic lego blocks and the sewer hose back there, so YMMV.

It's so ridiculous that Airstream uses steel for these boxes. If only they had access to some light, strong, rust-free material to make these boxes.


I had bumper boxes made for both of my vintage Airstreams with A-L-U-M-I-N-U-M. I know that aluminum can react badly to the juices from a black tank, but well-rinsed hoses have kept things clean and corrosion free for ten+ years.


Oh, and I also drill drain holes. No worries.

[Forester2]

After reading these I think I'm going to spray mine with truck bed liner and lose the mat.

[Sailorjamie]

https://photos.app.goo.gl/i9wvU1kFvA1KkSsC9

[Keys Dave]

I put dry-dec squares left over from use under the queen mattress in mine. Worked great.

[Rick n Mary]

My 1997 Safari originally had power, co-ax and telephone connections in this bin. Now just “stinky slinky” and adapters.
I.E., big hole to pull cables through. I have since put a “Smart Plug” in the side of trailer, so I no longer have power in bumper bin. I would clean and repaint in and outside of this bin.
IMO! drill several 1/8” holes for drainage! Like others have said, sand, clean (acetone, WEAR nitrile gloves,!)wipe and spray paint inside and out carefully!…. Eastwood. Com is where I get my “specialty” paints. They have a “etching rust encapsulation paint that works extremely well. 1/8” hole only you don’t want huge holes.
Good luck. Rick

[waninae39]

i bought rust-oleum hammered silver, no primer needed