Mercedes prepares ADUO as reliability crisis deepens
"The fact is that our reliability was simply not good enough"
Mercedes is reportedly preparing an upgraded ADUO power unit for Monza as reliability problems and renewed performance pressure threaten its strong start to the 2026 season.
The revised power unit is understood to feature changes to the combustion chamber, turbocharger and Petronas fuel, despite Mercedes initially planning to move away from further ADUO development and focus on 2027.
FIA found Red Bull-Ford to possess the strongest internal combustion engine, although the legality and application of ADUO remains contentious.
Max Verstappen confirmed Red Bull is still discussing the issue with the FIA. "You mentioned the engine," he said.
"Well, I would love to have some ADUO as well. Yeah, somehow. But that’s... I don’t know."
"We’ll see. We’ll have another look after the break."
As for Mercedes, it could introduce its upgrade at the Italian GP, but championship leader Kimi Antonelli has already reached the permitted limit of four power units and would therefore take a grid penalty.
Ferrari is also reportedly preparing an ADUO upgrade along with a new low-downforce rear wing for Monza.
Sky Deutschland pundit Ralf Schumacher says Mercedes can no longer afford to delay its next major upgrade.
"When we talk about upgrades, I found it interesting what Toto Wolff said," he said. He immediately let it be known that they have to look at the budget ceiling."
"That’s very interesting. Apparently they are already tight on cash, although I can hardly believe that in July or August."
"Wolff also pointed to Ferrari earlier and said he could not explain how they could continue to upgrade. Mercedes urgently needs to introduce an upgrade."
Reliability is an equally serious concern, with Antonelli and George Russell already using their fourth engines.
Russell required a replacement in Hungary after a water leak was detected following Q3, and Wolff admitted the damaged unit was "quite badly damaged" and may not be recoverable.
Wolff remains hopeful Mercedes can avoid penalties by returning to previously used components, but acknowledged Monza may become the logical place to introduce another engine.
"There’s one (race) that’s very special for Kimi, but it seems like a good place to take an engine change penalty," said the Mercedes boss.
"So I have to talk to (father) Marco about whether we want to take the penalty in Monza. We could take the pressure off his shoulders by starting from the back," Wolff joked.
"But the fact is that our reliability was simply not good enough. Whether we accept a penalty or not remains to be seen."