McLaren is having to wait at least another race to get hold of fresh Mercedes engines, despite other customers introducing them at Formula 1’s British Grand Prix.

Mercedes started rolling out new power units in Austria last weekend, on top of modified batteries, with works drivers George Russell and Kimi Antonelli the first to get hold of them.

While the latest version does not feature any performance upgrades that Mercedes is allowed under ADUO (Additional Development and Upgrade Opportunities), it does include reliability improvements.

These allow Mercedes to run it more confidently which, alongside typical gains that come from new engines that are not suffering from end-of-life degradation, were suggested by Mercedes boss Toto Wolff to have given it a minor power boost.

Speaking last weekend, Wolff said: “With that comes less mileage, comes a little bit more spiciness. But there was no upgrade in it, and at the moment there's no upgrade planned.”

Following its successful introduction by Mercedes in Austria, the latest specification power unit has started to be rolled out to Mercedes’ customers at Silverstone this weekend – but will not be running in all cars.

Alpine is fitting a fresh internal combustion engine (ICE) and turbo to both Pierre Gasly and Franco Colapinto's cars, which will be their third of the season.

At Williams, Carlos Sainz is to have a new ICE following the failure that put him out in Austria last weekend.

Williams’ other driver Alex Albon is sticking with what he has for now as he only fitted his most recent power unit in Spain, having been forced into the change as a consequence of a crash he had with Oscar Piastri in Canada.

It has emerged, however, that while McLaren had previously been on a similar timeline to the other Mercedes squads in moving onto its second power units in Miami, it will not be following suit in moving onto the latest specification just yet.

The team has not explained the reason why, but it is understood to be related to the fact that it has been told there is still mileage left in its current engine so there is no need to swap over just yet.

This is a consequence of its early season reliability woes, including its double did not start in China, which has left it behind on distance covered.

Decisions on the timing of the introduction of new power unit components are taken jointly by manufacturers and customers and influenced by a host of factors which includes availability of parts, mileage impact and team desires. 

There is also an accepted understanding that the works team will get priority over customers.

Based on mileage completed during the 2026 season, McLaren is adrift of other squads. 

Alpine, which has been moved across to the new power units this weekend, has completed more than 1200km extra distance so would be more in need of a change.

If McLaren adds a good chunk of distance onto its power units over Silverstone this weekend then it will almost certainly move to its third power units at the next race in Belgium.

TOTAL DISTANCE COVERED IN 2026 SO FAR

1. FERRARI 12,235km
2. MERCEDES 11,548km
3. ALPINE 11,165km
4. HAAS 10,912km
5. RED BULL 10,486km
6. RACING BULLS 10,327km
7. MCLAREN 10,267km
8. AUDI 10,053km
9. WILLIAMS 10,040km
10. CADILLAC 8121km
11. ASTON MARTIN 7932km

Works team versus customers

The staggered introduction of fresh power units comes in the wake of suggestions earlier in the year about works squads having an advantage with the current rules set.

The complex nature of the 2026 regulations has given manufacturers an advantage because they have been much further on with their understanding of exploiting them than customers.

And while that prompted some concerns from partner squads earlier in the year, Williams team boss James Vowles thinks differences in knowledge have started to close.

“That gap is closing now,” he said. “If you look compared to Melbourne and Shanghai, then probably what you're seeing around other tracks is the gap is closing between what we're able to extract and what they're able to extract as a result of it.

“And to be super clear, that is on us as an organisation. It's a matter of learning that we're having to do as a result of it.”

Vowles said he fully understood the reliability headaches Mercedes was facing, as he played down any talk of it making life difficult for customers.

“Mercedes are the best at doing this,” he said. “I maintain that. I have no questions or doubts about it in this circumstance. The reliability will improve. I'm confident of that as well. And the ways of working will improve as well.

“There is not an express interest in making our life difficult. It's just a very complex power unit and it takes a while to understand it all.”