Peugeot 407 2.0HDi TF-80SC gearbox feels strange

[FarokJanos]

Hello!

I have bought a Peugeot 407 2.0HDi made in 2007 which has the Aisin TF-80SC (AM6) gearbox.
Overall the shifting quality is very very nice, so much better than the AL4, but the downshift from 6 to 5 feels very strange, especially when the gas pedal is not pressed during the downshift:

6 to 5 downshift begins -> RPM drops to 1000 -> maximum ~0.3 seconds later it goes back to normal (between 1500 and 1800) -> 5th gear engages and everything is fine.

What could be the issue? All the upshifts and downshifts are smooth except the scenario which i have described. I do not know when the ATF was replaced by the prev. owner but I have already booked two appointments at my mechanic for 2 ATF replacements with 1 month period between the 2 changes so the ATF will be changed.

Thanks for any tips what could cause this behavior.

[mickthemaverick]

Have you had the two oil changes yet and if so how are the 6-5 changes?