They also try to avoid travelling in a convoy, because eating someone's dust is not much fun.

But over the last week on the Mid North Coast, 28 cars sporting sponsorship stickers have been clocking up hundreds of kilometres each day.

They're driving the roads less travelled as part of the Trek4Kidz, raising money to support hospitalised children and their families.

Joining the trek for the first time are father and son combo Ben and Simon Biggs from Urunga.

They've closed the family business, Ben & Sue Mechanical Repairs in Raleigh, for a week in order to participate.

Ben said he'd been looking for a way to "put something back into society" and Trevor Ledger from Macksville Wreckers suggested this.

"He's been on it a few times and he told me about it and I thought we'd give it a shot this year," Ben said.

Money is raised not only through sponsorships, but also auctions and raffles held in the towns where they stop overnight.

This year's event has already hit the $200,000 mark and in the 23 years that Trek4Kidz has been running, it's raised over $2 million for the Starlight Children's Foundation.

Everyone involved is a volunteer and they all pay their own way, so 100 per cent of the money is handed over as a big cheque at John Hunter Hospital in Newcastle.

The 2019 group hit the road in Gloucester and has been touring from 'Sapphires to Sand', taking in Mudgee, Armidale, Coffs, Wauchope and South West Rocks, finishing in Tuncurry on August 31.

Check out Simon's video of Day 3, where they travel from Armidale to Coffs via Ebor, Platypus Flats and Ulong, stopping for repairs and a school visit and wrapping up with a fancy dress dinner:

The Courier-Sun caught up with trekkers in Raleigh, where a few of them were taking advantage of a layover day to have their cars serviced by Ben and Simon.

One of the organisers, Dave Moore, explained there's nothing special about the cars - they're just a standard road-registered vehicle - the point is to get together and enjoy exploring regional Australia.

"You can use any type of vehicle you like but it's all dirt roads. The only time we drive on the tar is to get to the next dirt road," Dave said.

They drive from 8am to about 4pm each day, doing anything from 400 to 800 kilometres depending on conditions, and they're accompanied by a truck carrying auction items and refreshments.

"It's compulsory that everyone attend 'church' every afternoon at 4.30," Dave said. "That's where we meet at the back of the truck for beer and snacks."

After the rest day in Coffs on Wednesday, the trekkers were heading for Wauchope via the back roads of Bonville, Gleniffer and Thora.

Related: Smokin Simon Biggs burns rubber for a world record