It was only 1.8 points clear of Taranaki runner up Rowan Huckstep, while Manukau driver Phillip Walton made a big comeback during the afternoon section, conceding less than half the total of the other Top 10 drivers, to get up to third overall.
Auckland's Scott Biggs, a two-time series runner up, came into the Manawatu round with momentum with two victories, but after leading from Huckstep and Auret respectively in the morning session, he picked up some costly points on the 18th hazard in the afternoon, which dropped him back to fourth.
In the six-round competition, drivers can remove their worst result from their final season tally, and while Auret had finished in the Top 5 at all the previous rounds, he was still technically trailing Biggs and Walton under that system.
He needed to get a victory and having achieved it with a wider points spread on Biggs and Walton, thanks to Huckstep, will certainly help.
"Definitely happy with that, it's a release [of tension], probably," said Auret.
"There was a couple of people between us and Scott - that pushes him back.
"The pressure's more on them – each result we can use.
"Everyone wants it so badly. They're desperate for it.
"If they have another shocker, they're gone."
Having been to the Mangamako Rd a couple of times previously for events, Auret said he was pleasantly surprised with the alterations the organisers had made.
"Normally it's far too easy. This time they put in some tough finishes to the hazards."
The team came through the day with no breakages, but did have one scary moment when Auret went full force up one obstacle and over-compensated on power.
"We decided to attack the bank at full speed and we just went straight up vertical."
It would not have taken much for the truck to rotate over and possibly cause serious damage, but Newton's Third Law stayed in their favour and their Chev 6 litre truck came back down on its tyres.
"Luckily we landed nicely. Hanging in the air for a fair while, a long time since I've been that high."
Of the other Whanganui connections competing in Rangiwahia, Grant Harrison finished fourth in C-Class and 20th overall with 347.36 penalty points, while Mike Gee-Taylor, who was one of the hosts, finished 21st in D-Class and 26th overall, with 403.4 points.
The fifth round of the series will be on March 24 in Taranaki, hosted by the Mt Egmont 4Wheel Drive Club, before Wanganui 4WD Club will host the final round on April 14.