I used to have an aluminum lumber rack that mounted to the top of the between the bed and the shell and am looking for another one.
It was called "Hauler Rack"... I think it headquartered out of So. Cal.

Can anyone tell me what company has a good aluminum rack for a shelled truck?

 

The only ones I have seen for a cap, are made of steel. You take the cap off, install the rack and put cap back on. Those steel ones are heavy duty and can take a lot of abuse.

 

Is this what you are wanting?

Hauler Racks - CAP Racks, Camper Shell Racks, Topper Racks

 

I guess Hauler Rack is the only major brand out there that offers aluminum over a shell. I was hoping there might be another company that offers a comparable product.
I used to have a Hauler Rack one on my last Ford Truck and used it all the time. Especially since it was a short bed.
I ordered a couple aluminum slats that go across the frame to make the ladder frame accept shorter material as they only come with 3 slats for the short bed version this made it 5 across. Surprisingly strong design but it did flex when loaded.
I noticed they're rated at 1,000lbs!

 

There is a company here in NC that manufactures really nice racks but I don't recall the name. There was an FTE thread several years ago where the FTE member posted pics of his unit. When I have time, I do a search.

EDIT: Here is the FTE thread:
https://www.ford-trucks.com/forums/9...ork-truck.html

Vendor Website:
http://ryderracks.com/