Storage on any RV is always in short supply. I have a family of five in my GMC Palm Beach so I needed more space. The RV has a good sized closet but we filled it up with camping chairs and a rug for outside. Getting that stuff out of the closest would be great.

I had seen many GMC motorhomes had the same style of plastic or fiberglass roof top carrier. It is ribbed, longer than it is wide, and no taller than the roof mounted A/C. My wife loves vintage things as much as I do and managed to find an original one near by. She got it for me as a Christmas present. The original owner removed it to make room for a roof full of solar panels.

The main body of the carrier was in good shape. The bummer was that it was screwed into the roof with 12 sheet metal screws. They just went into the sheet metal, not the main ribs. And all the plastic around the screw holes was cracked. Plus the rubber gasket around the screw holes was also worn out. I decided I would utilize a completely different mounting system.

I patched all the original screw holes with giberglass resin and matte. The carrier was once again water tight (within reason). Now I was free to come up with a new mounting system.

I opted for a seemingly complex but sturdy and water tight approach. I ran 4 long bolts through the roof ribs from the inside of the RV to the outside. The carrier wouldn't just pull on the sheet metal skin, it would pull on the main support ribs. On the roof, I installed a rubber gasket and a fender washer on the bolt. Then I applied red locktite to a nut. The bolt is now secured to the ribs and has a water tight seal. But the carrier isn't mounted yet. This nut and bolt are meant to stay in place forever and should never be removed.

Next I drilled out 4 holes in the bottom of the carier so that it sits over and around the 4 bolts and nuts. So the carrier sits directly on the roof with the nut and bolt protruding through a hole in the carrier.

Next I installed a thick washer with a large I.D. to go around the nut and extend above the top of the nut. I followed this up with another fender washer and a nut. A this point the carrier is bolted down to the roof and the load is distributed across 4 nuts sitting on large fender washers. I could have stopped  hear. But if its worth doing, its worth over-doing.

I then installed steel strips over the bolts. So now the steel strip is half resting on the corrugated floor of the carrier and half resting on the nut from the step above. I then secured it with a nut. Now if the wind pulls the carrier up, the load is spread over the entire width of the carrier rather than concentrated on a couple fender washers.

Finally I cut the length of bolt still sticking out. Then I installed a rubber cap over the exposed nut so that it didn't rip whatever I put in the carrier.

This seems like a complicated setup. And it is. But here is why I chose this approach.

1. The roof top carrier can be removed without breaking the water tight seal on the roof. You unbolt the carrier from the roof entirely from the outside of the vehicle and leave behind the mounting bolt and bottom nut. You never have to take down your ceiling to get at the 4 bolt heads.
2. The carrier is held down tight to the roof with 4 nuts on fender washers.
3. The wind pulling up on the carrier has the force distributed across two metal strips that are each the full width of the carrier. There is zero chance that highway speeds will successfully pull on the carrier to the point the plastic around the bolts fail.

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Smll Med Lrg	Smll Med Lrg It will fit in this open space	Smll Med Lrg	Smll Med Lrg
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Smll Med Lrg All 12 original screw holes will be patched with fiberglass	Smll Med Lrg	Smll Med Lrg all the screw holes are cracked anyways	Smll Med Lrg
Smll Med Lrg	Smll Med Lrg	Smll Med Lrg	Smll Med Lrg I left the smooth part on the inside of the carrier
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Smll Med Lrg	Smll Med Lrg test fit	Smll Med Lrg	Smll Med Lrg
Smll Med Lrg The front roof rib I will be using	Smll Med Lrg	Smll Med Lrg	Smll Med Lrg
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Smll Med Lrg	Smll Med Lrg	Smll Med Lrg	Smll Med Lrg The rear roof rib I will be using. It has holes already. Too bad that are full of hard rubber
Smll Med Lrg	Smll Med Lrg Bolts run up from inside the RV, with a rubber washer, fender washer, and bolt on top	Smll Med Lrg This nut and bolt should never be removed. So I used some red locktitght	Smll Med Lrg
Smll Med Lrg	Smll Med Lrg	Smll Med Lrg	Smll Med Lrg Now all bolts are in place. The carrier isn't yet held down by those bolts
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Smll Med Lrg	Smll Med Lrg This is a test fit of steel strips that distribute pulling force across the entire carrier floor	Smll Med Lrg	Smll Med Lrg
Smll Med Lrg	Smll Med Lrg everything is fitting	Smll Med Lrg This is the nut that holds the bolt to the roof. Drill the carrier out so it sits around this nut	Smll Med Lrg
Smll Med Lrg use more washers so we clamp the carrier down around the original nut	Smll Med Lrg now put the metal sctrips on top	Smll Med Lrg	Smll Med Lrg 3 nuts in total (1 under those washers). May seem like overkill but there is a good reason
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Smll Med Lrg	Smll Med Lrg	Smll Med Lrg	Smll Med Lrg The carrier can fit a ton of cargo. I love it.
Smll Med Lrg	Smll Med Lrg Later I installed a 200 watt solar panel but that is a different project