Western Australian premier Mark McGowan attended an event at Austin's manufacturing facility in Kewdale, outside Perth, and unveiled the high-performance ULITMA truck body.

McGowan said he was pleased to see the strength of WA's manufacturing sector on display and praised Rio for its commitment to purchasing locally made truck bodies.

Austin CEO David Singleton said the partnership with Rio started 33 years ago.

"We built the first original bucket for Rio Tinto 21 years ago and we built the first fully customised body for Rio Tinto 14 years ago," he told staff and guests.

"It's been an association that has grown and developed over time. Importantly, it's been a partnership that has created a strong Western Australian business that has employed thousands of Western Australians over the years, and now takes Western Australian products to the rest of the world."

On an earlier tour of the facility, Rio Tinto Iron Ore boss Simon Trott said he'd been impressed by the innovation on display.

"That's exactly the sort of partnership that we want, we want to be focusing on problems together and absolutely, we've each got our commercial interests and we've each got our businesses to run,  but the more we can focus jointly on issues, identify them, resolve and move forward together, it makes our business stronger and it makes your business stronger as well so it was really was fantastic to see," he said.

Austin is investing A$6.5 million to implement advanced manufacturing processes and capabilities at its Perth and Batam (Indonesia) sites, including increased automation and the use of custom jigs, fixtures, workstations and a standardised manufacturing approach to building products.

The Kewdale facility is currently receiving the first manufacturing upgrade, which will benefit major customers, such as Rio, and enhance the company's supply of Western Australian-made dump truck bodies and other hauling and loading products.