I have an 08 mazda 3 with roughly 77,000 miles. 5 speed auto trans. Just recently the CEL came on as well as the AT light, the car would not shift higher than third gear. Took to the dealer, was due for a transmission flush so I had them do that there while diagnosing my problem. Fluid was dark. The mechanic stated he got an occasional code of P0753, shift solenoid A malfunction. After my flush I was on my way with a brand new feeling transmission. Drove it about 50 miles till the problems came back. It's scheduled to go back Friday to get that solenoid replaced. My question is, should I be planning on dropping cash here for a new transmission or should I feel confident it's a solenoid issue? I just can't keep dropping $300 at a time on a transmission that may be junk!