Car #55 continues to sport major backing from Castrol but now features more block colour, as well as a hint of the oil brand's iconic ‘tic tac' livery from 2002 and 2003 on the bonnet.
The 2023 Repco Supercars Championship season will be Randle's second as a full-timer, after finishing 23rd in the standings last year.
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The 2020 Super2 Series winner said, “2022 was definitely a rollercoaster of year for myself, we had some great moments, and also plenty of challenging ones as well.
“I certainly learnt a lot and I am really keen to take those lessons into this next generation of cars and move forward.
“I felt like we were really starting to show our potential at the back end of the season so I'm looking forward to continuing that momentum with my engineer Ray [Lau] and the whole Car #55 crew.
“It's exciting to be a part of this next generation car, it should be great for the fans to see the close racing on track and hopefully they'll see the Castrol Racing Mustang back at the top.”
The #55 Mustang will be the second Gen3 car out of Tickford to have its shakedown, which is set to get underway in hours.
It will be joined at Winton by the #6 Mustang of Cameron Waters, which will officially be put through a test day after being shaken down by the two-time Bathurst 1000 pole-sitter in recent days.
Randle added, “I have been working very hard over the off-season and the team has been putting in maximum effort in preparing the new cars and working on how we can get on top of them. I feel I'm as prepared as I can be.
“With these new regulations, it will be interesting to see each team's approach.
“Newcastle will undoubtedly be a great event to have back and it will be a learning curve for everyone, making it a great opportunity for it to be anyone's game.
“I'd love to get some great results to reward the team and also our loyal partners and members.”