I am driving Mazda 3 2008 with 115K mileage, now I am facing with weird issues while driving my car, every time I reached gear 4 with 80kph to 100kph speed it shifts automatically to gear 3 or gear 2, or even I'm on 60kph speed on gear 3 it change to gear 2 and I feel like the it consumes more petrol than usual driving.
I didn't experience this issue before, can anyone advice me on how and where to fix this issue? I'm planning to bring my car to Mazda Service Center but I'm also thinking of different service center coz Mazda might rip me off with the charges.
Your advice would be much appreciated.