Hamilton has been driving Mercedes’ chassis number six all season, with Bottas now taking on that base and the Briton switching to chassis number four instead.
Bottas underwent another chassis change earlier in the year in the aftermath of his enormous crash with George Russell in Imola, but the team have kept spare chassis bases from last season to carry over if needed.
Mercedes team principal Wolff was clear that the move was made to ensure the cars do not rack up too many miles and lose performance over the course of the season.
“We swap parts around all the time, and this is part of the planning – to carry over chassis for a second season so we’re not accumulating millions of miles on one. Basically, it’s part of the plan,” the Austrian told Sky Sports F1 after second practice.
“But it’s good to get the feedback and if it calms the driver’s mind, we have a spare chassis which is a brand new one – we can always do that.”
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Bottas was faster than the seven-time World Champion in both free practice sessions on Friday, with the Briton complaining that “there’s something not right with the car” to race engineer Pete Bonnington during FP2.
But while the Mercedes team principal was quick to dismiss any ideas of a lack of performance on one chassis compared to the other, he said he would take the drivers’ feelings into account and, if they do not feel comfortable in their cars, he will ensure their chassis is swapped again.
“It was the chassis that was splendid [for Bottas] in Monaco, that qualified Valtteri right in [the] front,” Wolff added.
“But you never know [if there are differences], you listen to the engineers who said it’s all tested and stiff, there shouldn’t be any difference.
“But if the driver feels that it’s not, then it’s definitely not worth trying to make a point here and you just need to change.”
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