It was a nightmare end to a nightmare day but Ford star Will Davison is just thankful he walked away from a spectacular brake failure at Sunday's Bathurst 1000.

After a day where he went from leading the race in the opening laps to struggling at the back of the field following a series of mishaps, Davison found himself in every driver's worst scenario as he barrelled down Mount Panorama's back straight at 300km/h with no brakes.

A broken rear roll bar had severed his brake lines, leaving Davison a passenger as his Falcon sped through the kink in the straight called the Chase.

The car ploughed through a gravel trap before crossing the circuit, sideways, just as Fabian Coulthard's Commodore passed by.

Then another gravel trap successfully reduced Davison's speed as his car came to rest against a wall near the final turn of the iconic 6.2km circuit.

A shaken Davison said the terrifying sequence had been the hairiest moment of his racing career.

"If anyone ever tells me I'm overpaid again, I'll tell them to go jam it. Should be paid double," Davison told AAP.

"It's moments like that you hope are never going to happen, fortunately I've somehow walked away but if any driver could have any worst fear it's a brake failure at the Chase.

"The moment I left the track ... it's just terrifying.

"I thought it was going to dig in and start barrel rolling ... there's that split second there where you feel extremely exposed to major injury.

"I'm just massively relieved."

Davison's eventual 24th place finish has all but scuppered his hopes of winning this year's V8 Supercars championship, given he now trails leader Jamie Whincup by 470 points with four races left in the year.

"It's not impossible but it's certainly a long shot," he said.

"I'm not even thinking about it."