What 5 R's are Aluminum Framed

Lots of them My 04 Keystone is as was my 05 Rvision.

Virtually all of the mid to upper level fivers are aluminum framed. What is your budget, and what are you looking for?

I believe all Carriage models are aluminum. No longer in business but still highly regarded as upper class fivers. Mine has the following construction:
Box Tube Aluminum Roof Trusses and studs.
2 x 3” Welded Aluminum Main Floor
Sub floor is 12” Doublestacked Box Tube Steel Main Frame
Sidewall is Gel-Coat Fiberglass with 2” Box Tube Aluminum

Newmar fivers had aluminum framing in the walls and roof. I know '05, not sure of other years.

Newmar brochure archive

I assume you mean wall studs not chassis frame. My Cardinal is aluminum studs and roof trusts, with vacuum bonded gelcoated walls.