Transmission not shifting to 4th or 5th after using Mazda M3 fluid for one change

[juniorsenior]

I have since flushed the transmission out with Mazda M-V and it will occasionally shift to 4-5 while in Drive, other times it will sit in 3rd or 4th at like 4k rpms at the same speed. I can shift into 'manual' and change the gears or I can activate cruise control and it will upshift. This problem did not occur before I touched the fluid.

Should I continue flushing? Could there be a solenoid problem?

Thanks all

 

[teetee1]

At how many miles was the changed and has it been changed before? It sounds like the friction plate did not get enough friction, common reason not to do the flush on a already worn-out transmission.

 

[juniorsenior]

I changed it at approximately 100k, and it was changed before (thought I only got the car at 85k with fresh looking fluid in it).

Do I just live with it? Will the transmission fail or just need to be "manually" shifted into 4 and 5 and be fine?