In February, the company launched the Huntsman for $69,900 and the Adventurer for $79,990.
Winnebago Industries managing director Bruce Binns said more new models would be released later in the year.
The Winnebago Adventurer 1952 is a self-contained motorhome.
"The Adventurer fills the gap in our already extensive model line-up as an affordable alternative for many people wishing to get away regularly and enjoy life," Binns says.
The Adventurer is available in a five-speed manual transmission on a Fiat Ducato Chassis and a four-speed automatic transmission variant on a Ford Transit chassis. An all-wheel-drive version is also available.
Built by hand at the Winnebago factory in outer Sydney, the Adventurer features a self-contained bathroom, shower and cassette toilet system; diesel furnace heater and hot water system; 12-volt lighting system; slatted double bed; three-seater dinette; swivel lounge chairs; 100-litre three-way fridge freezer; two-burner LPG stove; external and internal storage space; and smoke detector and fire extinguisher.
Additional luxuries including airconditioning, ducted heating, a rear-vision camera, a roll-out awning and an LCD television finish off an already attractive package.
The Huntsman 1902 is Winnebago's smallest model.
Based on a Toyota Hilux chassis, it is available in a range of models, in petrol (from a 2.7-litre manual to a 4-litre V6 automatic) and diesel (3-litre manual and automatic turbo diesel).
The Huntsman features include self-contained bathroom, shower and cassette toilet system; 12-volt lighting system; gas hot water system; comfortable double bed; 90-litre fridge freezer; microwave oven; and smoke detector and fire extinguisher.
Winnebago Industries, which was established in 1965 by Binns, designs and hand-builds more than 70 models from 10 ranges.