London: Red Bull will switch Sebastian Vettel`s chassis for next week`s Turkish Grand Prix after finding a defect in the car he used in Monaco last weekend, team boss Christian Horner said.
Horner told reporters that the change was being made as a precautionary measure.
"We found the chassis had a minor defect," he said. "It looks as if it is an issue that deteriorated during the race in Monaco."
Vettel`s Australian team mate Mark Webber has won the last two grands prix in Spain and Monaco, with Vettel runner-up in the Mediterranean principality.
The German is second overall in the championship, level on points with Webber but behind 2-1 on race wins. Webber has started the last two races on pole position.
Horner said the problem with the chassis was detected in the post-race inspection back at the factory and tallied with comments Vettel had made about his car`s handling during the last race.
He said the chassis that the 22-year-old would now use at Istanbul Park was not new but one that had been raced earlier in the season.
Webber finished second to world champion Jenson Button in Turkey last year, with Vettel third.
The Red Bull drivers will be favourites to win this year, with the team already leading the constructors` championship.