Past Cherokees and Grand Cherokees were built with unibody chassis, not sure if they upgraded to new ones to a full frame. Just about all Cherokees would start getting body sag as the vehicle got older, you would have to lift up on the door to close it. Past 4Runners were build with full tubular frames, pretty sure the new ones are built the same.

Personally I wouldn't consider a unibody for even a occational off road vehicle.