| Moysey | B. | Lake Grace | Ford Truck | LG ● 45 | Lake Grace Road Board | 1927-28 |
| Mozzoletti | P. | Bridgetown | Chevrolet Truck | B ● 17 | Bridgetown Road Board | 1927-28 |
| Mrs Maud | James | Three Springs | Dodge | MI ● 8 | Mingenew Road Board | 1923-24 |
| Mrs Thomas & Sons | - | Ravenswood | Ford | MY ● 22 | Murray Road Board | 1922-23 |
| Mt Augustus Pastoral Co | - | Mount Augustus Station | Dodge | GU ● 40 | Upper Gascoyne Road Board | 1926-27 |
| Mt Lyall Chemical Works | - | North Fremantle | Ford Truck | 7139 | Metro Private Car | 1925-26 |
| Mt Marshall Road Board | - | Bencubbin | Overland | MM 45 | Mount Marshall Road Board | 1924-25 |
| Mt Marshall Road Board | - | Bencubbin | International Truck | MM ● 63 | Mount Marshall Road Board | 1926-27 |
| Mt. Lyall Chemical Works | - | North Fremantle | Ford Truck | 7139 | Metro Private Car | 1926-27 |
| Mt. Lyell Chemical Works | - | Rocky Bay Fremantle | Ford | 6007 | Metro Private Car | 1924-25 |
| Mt. Lyell Chemical Works | - | North Fremantle | Ford | 2764 | Metro Private Car | 1924-25 |
| Mt. Lyell Chemical Works | - | North Fremantle | Ford | 2764 | Metro Private Car | 1925-26 |
| Mt. Lyell Chemical Works | - | North Fremantle | Ford | 2764 | Metro Private Car | 1926-27 |
| Mt. Lyell Chemical Works | - | North Fremantle | Ford | 2764 | Metro Private Car | 1927-28 |
| Mt. Lyell Farmers Fertilliser Co | - | North Fremantle | Ford Wagon | 12687 | Metro Private Car | 1927-28 |
| Mt. Margaret Road Board | - | - | Ford Truck | MG ● 10 | Mount Margaret Road Board | 1926-27 |
| Mt. Margaret Road Board | - | - | Ford Truck | MG ● 34 | Mount Margaret Road Board | 1927-28 |
| Mt. Rupert Co | - | Wongan Hills | Chevrolet Truck | WB ● 160 | Wongan-Ballidu Road Board | 1926-27 |
| Mt. Rupert Co | - | Wongan Hills | Dodge Truck | WB ● 161 | Wongan-Ballidu Road Board | 1926-27 |
| Mt. Rupert Co | - | Wongan Hills | Chevrolet Truck | WB ● 160 | Wongan-Ballidu Road Board | 1927-28 |
| Mt. Rupert Co | - | Wongan Hills | Dodge Truck | WB ● 161 | Wongan-Ballidu Road Board | 1927-28 |
| Mt. Weld Pastoral Co Ltd | - | - | Ford | MG ● 6 | Mount Margaret Road Board | 1927-28 |
| Mt. Weld Pastoral Co Ltd | - | - | Ford Truck | MG ● 7 | Mount Margaret Road Board | 1927-28 |
| Muccan Pastoral Co | - | - | Austin | MB ● 3 | Marble Bar Road Board | 1927-28 |
| Muccan Pastoral Co | - | - | Federal-Knight Truck | MB ● 28 | Marble Bar Road Board | 1927-28 |
| Muck | Mrs C. | Gingin | Dodge | GG ● 1 | Gingin Road Board | 1925-26 |
| Muclloch | W. | 19 Victoria Street | Jewett Hire Car | K ● 1 | Kalgoorlie Road Board | 1926-27 |
| Mudge | A. L. | Wagin | Gray | WN 40 | Wagin Municipality | 1925-26 |
| Mudge | A. L. | - | Gray | W ● 146 | Wagin Road Board | 1926-27 |
| Mudge | A. L. | - | Gray | W ● 146 | Wagin Road Board | 1927-28 |
| Mudge | E. C. | 10 Chester Street, Subiaco | Oldsmobile | 11136 | Metro Private Car | 1926-27 |
| Mudge | E. C. | 10 Chester Street, Subiaco | Oldsmobile | 11136 | Metro Private Car | 1927-28 |
| Mudge | H. | Wagin | Chevrolet | WN 38 | Wagin Municipality | 1926-27 |
| Mudge | H. S. | Wagin | Chevrolet | WN 38 | Wagin Municipality | 1927-28 |
| Mudge | John | 17 Attfield Street, Fremantle | Morris-Cowley | 12322 | Metro Private Car | 1927-28 |
| Mudge | R. A. | 265 York Street | - | S 24 | Subiaco Municipality | 1919 |
| Mudgedeen | M. | Kirkham Terrace, Maylands | Overland | 13607 | Metro Private Car | 1926-27 |
| Mues | William | Meenaar | Ford 20 H.P. | N 15 | Northam Road Board | 1919 |
| Mugridge | Miss P. | 11 Irvine Street, Cottesloe | Austin | 4264 | Metro Private Car | 1927-28 |
| Muhleinson | J. T. | 117 Broome Street, Cottesloe | Oakland | 4966 | Metro Private Car | 1925-26 |
| Muhleison | F. J. | 442 Lord Street, Mount Lawley | Dort | 7481 | Metro Private Car | 1925-26 |
| Muhleison | J. T. | 117 Broome Street, Cottesloe | Oakland | 4966 | Metro Private Car | 1924-25 |
| Muhs | W. | Kathleen Avenue, Maylands | Ford | 4957 | Metro Private Car | 1924-25 |
| Muhs | W. | - | Chevrolet | NA ● 61 | Nungarin Road Board | 1924-25 |
| Muhs | W. | Nungarin | Ford | NA ● 61 | Nungarin Road Board | 1925-26 |
| Muhs | W. | Nungarin | Chevrolet | NA ● 61 | Nungarin Road Board | 1927-28 |
| Muir | A. | Shackleton | Ford 20 H.P. | AE ● 6 | East Avon Road Board | 1917-18 |
| Muir | A. | Shachleton | Ford 20 H.P. | BR ● 6 | Bruce Rock Road Board | 1919 |
| Muir | A. | Albany | Studebaker | A 54 | Municipality of Albany | 1925-26 |
| Muir | A. | Forrest Hill Nab | Dodge | WA ● 43 | Manjimup Road Board | 1925-26 |
