Gounon, a three-time Bathurst 12 Hour winner, will partner the Groves in a Mercedes-AMG GT3.
The Gulf 12 Hours takes place at the Yas Marina Circuit, home of the Formula 1 Abu Dhabi Grand Prix.
This year’s race is set for December 15 and entries are invite-only.
Grove Racing will race under the 2 Seas Motorsport banner.
Gounon has never raced alongside the Groves and said the 12-hour race is a long time coming.
“I am very happy to be back with the guys at 2 Seas Motorsport,” said the factory Mercedes-AMG driver.
“We came together and did a great job last year in Abu Dhabi, securing the Intercontinental GT Challenge title, so it’s a pleasure to be back.
“I’m also really pleased to join the Grove family for this event. We have been working hard for some time to make it possible to race together, so I am delighted that we have been able to make this all come together for the Gulf 12 Hours.
“Really looking forward to a fun weekend with everyone and hoping we can bring some silverware home to sign off the year.”
This year’s Gulf 12 Hours marks the first time the Groves have returned to Abu Dhabi since Stephen’s high-speed crash in 2023.
“Yas Marina Circuit is one of my favourite tracks, and returning for the Gulf 12 Hours, in the premier GT race, is an incredible way to close out the year,” said Stephen Grove.
“The Mercedes-AMG has been fantastic, and we’ve learned a lot about how to maximise its performance this season.
“I’m excited to utilise all that knowledge to forge a strong result at the Gulf 12 Hours.
“Beginning our partnership with 2 Seas Motorsport is another thrilling aspect, and their meticulous preparation of the car has been impressive.
“It’s also a privilege to team up with a driver of Jules’ calibre, and I’m eager to learn as much as possible from him.
“He’s an incredible professional and there will be high value in observing his preparation, as well as his technique and outright speed throughout the weekend.”