A series of crankshaft failures at Sandown last month forced Ford to act quickly to diagnose the cause of the issue and implement a fix ahead of the Great Race.

That has resulted in Ford sourcing a new batch of 10 crankshafts from its GT3 program.

Seven engines fitted with the new parts arrived at the track this morning while the remainder are expected this afternoon.

“It’s been an absolute power of work to get to here,” Ford Australia’s motorsport engineering lead Brendan McGinniskin told Speedcafe.

“Between Dick Johnson Racing and Ford Performance in the States, it’s literally been a miracle to get them all to turn up, particularly pre-event.”

Alarm bells were raised when Grove Racing’s Richie Stanaway suffered the first failure in the race at Sandown with an engine that had recently been rebuilt.

Two further crankshaft failures occurred in Dick Johnson Racing and Walkinshaw Andretti United Mustangs during the ride day on the Monday after Sandown.

“From all of the work we’ve done, it appears to be a supply quality issue,” affirmed McGinniskin amid varying theories on the root cause of the failures.

“We’ve done a bunch of analysis on what’s changed from last year to this year and it purely looks like it is supply quality.

“We had some theories around the inertia components we’d swapped out from ’23 to ’24, we’ve gone and done the work and it doesn’t look like that is a contributor.

“We gradually crossed things off the list and it came back to appearing like the quality coming out of (supplier) Callies has just degraded over time and that’s what we appear to have been dealing with.”

The Ford engine adopted a smaller harmonic balancer for 2024 amid changes to match its Moment of Inertia with the Chevrolet.

Efforts to determine if the balancer was the cause of the issue included Cam Waters driving Tickford Racing’s spare Mustang around the speed bowl at the You Yangs Proving Grounds.

The test undertaken by Waters was also replicated at Queensland Raceway, where Anton De Pasquale, Will Davison and Aaron Love all shared a Blanchard Racing Team Mustang.

The GT3 crankshaft clocked up over 1000km of running during the Queensland Raceway testing.

“We tested at the You Yangs on the Callies crank, we walked through from ’23 to 2024 and the proposed balancer that’s on the engine now,” said McGinniskin.

“Nothing really stood out to say that what we’d done between last year and this year was the silver bullet or the Eureka moment as far as that being the answer.

“It looks like the changes we made for parity reasons over the off-season had practically no effect on the failures we’d seen.”

The cranks supplied from Callies are understood to be manufactured in China, while the GT3 units are theoretically the same material, but come out of Ford’s own foundry in Mexico.

Sourcing enough of the GT3 cranks proved a major challenge. They were brought in from the US and UK via Japan, where they had to be balanced to suit the Supercars engine.

“Originally, we were thinking we were only going to have three, which is why it was reported that only maybe a few will get them and who’s going to get them, it was a bit contentious,” he said.

“The Ford Performance guys in the US managed to work some miracles and call in some favours and scoop a few up that were sitting destined for GT3 engines.

“They were sent back to Japan and specced to suit our engine package.”

McGinniskin also revealed discussions were underway prior to Sandown to switch to the GT3 crankshaft for 2025, following crank failures on WAU cars during post-event ride days in Perth and Sydney.

“When we had an issue early in the year we started investigating the possibility of bringing this in for ’25,” he said.

“It was a much longer lead time given what you’ve got to go through to make sure it’s machined to our spec.

“It wasn’t just a matter of dropping the crank in and going racing, we were going through the process of having it machined to suit our package and obviously the GT3 package is slightly different.

“It was ‘let’s look at this for 2025’. It just so happened that the failures at Sandown put a bit of an acceleration on that plan and here we are.”