Hello Lynn,
I am not sure whether the models were named differently in Australia as they were in New Zealand? Both the vehicles I posted photographs from two different sellers who are located in different states of Australia are advertised specifically as four wheel drive "S" model trucks.
Queensland -
Bedford Truck 4x4: Bedford Truck 4×4 S Model, runs well Accessed from,
http://pricestruckparts.com.au/bedford-truck-4x4
New South Wales -
1956 Bedford S Series 4wd Accessed from,
https://www.justtrucks.com.au/trucks...4wd/JTM3945607
The truck in Tony's brother's photo may not be an S Model - it certainly looks like either an R or and S model Bedford though. I only have experience with the TK Bedfords that came after the S model in Australia. When I worked for a local council's Parks department it was a former garbage truck that had been modified for a new role as a woodchipper truck. It was only two-wheel drive. It was hot, noisy, rough as guts and it developed a unique smell during the summer inside the cab as lingering tribute to its former role.
Kind regards
Lionel