I had changed the transmission oil a while ago (about 1.5years), and as time flew by and life slowed down recently I've had more time to devote to doing a full round of fluid changes again (with the exception of the oil, I kept that around the 5k mark). In that time I've put on over 50k miles. So I checked the transmission oil and it was dark.

question is, since I've started changing out the fluid the shifting seems a lot more "firm" or "stiff" or possibly another description is "harder shifts". Is this normal? I don't remember this happening the last time around.