Felipe Nasr will receive a new chassis at this weekend's Russian Grand Prix after the youngster's complaints across the opening three rounds of the season.
Nasr has so far trailed team-mate Marcus Ericsson in 2016, finishing 15th in Australia, 14th in Bahrain before slumping to 20th in China.
Nasr has been uncomfortable with the handling of Sauber's C35, and requested the change for this weekend's race.
"Yes I can confirm I do get a new chassis, although you have to remember an F1 car is made of many components and it is just one part of it," he said.
"It’s a sensible step from the team to discover further these issues that I'm having, these handling issues [I've had] since we put the car on track in Australia.
"We’ve been having this strange behaviour, very unpredictable to drive the car, and let’s see how the weekend goes."
Nasr finished sixth in Russia last year, having also finished on the podium in GP2 at Sochi, and is planning to use that previous good form as a reference.
"There’s so many places to look at and for this we need the resources, we need time, the cars haven’t been back at the factory," he explained.
"It’s good to have a full look at every detail if we could but I am sure they [Sauber] are doing everything they can, it’s a good step to see if there’s anything wrong with the chassis.
"It was great here last year, I had one of my best races in F1, it's a track I like, so at least I have this good reference in my mind."