Update: The BP fuel truck that caused a triple fatality when its trailer became detached in the state's north-east had been serviced last week, the company says.
Investigations are under way into the crash, which happened about 9.30am on Thursday on the Yackandandah-Wodonga Road in Staghorn Flat, about 15 kilometres south of Wodonga
Three dead in petrol tanker crash
BP has recalled its Victorian trucking fleet after one of its petrol tankers crashed in northeastern Victoria killing three people including one child.
It claimed the lives of a 67-year-old Yackandandah woman in one car and a woman, 33, and her four-year-old son, from Allans Flat, in a second vehicle.
On Friday, BP Australia president Andy Holmes announced an Australia-wide recall of the company's fleet.
"We are co-operating fully with the investigations currently under way by the authorities and as a matter of precaution I've decided to recall BP's trucking fleet," he said.
Mr Holmes said the truck involved in the crash - a "truck and dog trailer" - had been serviced on August 1 and had a full roadworthy inspection in May this year.
It was the only vehicle of its kind operating for BP in Victoria, he said.
About 50 BP trucks had been taken off the road, including about 30 from Victoria, Mr Holmes said.
VicRoads started conducting safety checks on the company's Victorian fleet at a maintenance centre in Williamstown North on Friday.
Richard Bell, VicRoads director of regulatory services, said VicRoads was working with BP to "ensure all the vehicles are safe as they return to the road."
Mr Bell said inspectors had found only minor issues in the first three vehicle inspected, which were not serious enough to affect safety.
Police said the truck driver, a 50-year-old local man, who was not injured, had been helping with their inquiries.
Ambulance Victoria spokesman John Mullen said it appeared part of the petrol tanker had rolled onto the vehicle.
"A trailer has come away from the truck, it sounds like it's a petrol trailer, and that trailer has rolled onto a car," he said.
Local resident Jacqui Scott said the deaths would devastate the small community, which was still coming to grips with the deaths of two young local girls who were killed in a crash near the same stretch of road in January.
"It's generally the locals using that road, so I was concerned it might have been locals involved and have been calling around neighbours," she said.
The Major Crash Investigations Unit arrived at the scene mid-afternoon on Thursday.
A BP spokesman said the truck recall was unlikely to affect road users because most fuel was carried by external transport companies including Linfox and Toll.
"We actually move most of our fuel through third parties ... so because of that we're not really expecting any significant impact on petrol supply," he said.
It is unclear how many Melbourne petrol stations are serviced by the trucks.
Major collision investigation unit detective inspector Bernie Rankin said police were running tests to establish the reason part of the tanker was able to come loose.
"That will all be part of a our report for the coroner," he said, adding that all heavy vehicle operators had an obligation to maintain safe standards.
Police have asked that anyone who witnessed the crash to contact Crime Stoppers on 1800 333 000.
with Beau Donelly