Currently my automatic sedan has a cat back exhaust and intake, nothing else. Just recently I started to experience shift flare above 4k rpm in the higher gears, only after I added the exhaust. Could a change this small be the cause? It's a solid second or two before it finds the next gear, similar to missing a shift with a manual transmission. I'll be taking it to the dealer Monday but was curious if just having the tranny flushed and topped off has actually helped anyone with this issue. I have also heard the dealership may just reflash the car and that fixes it? Seems almost too good to be true. Thoughts?