Thread: Braking issue with my D4

Originally Posted by cruiseh

Any chance its just a gearbox downshift thing? ive noticed mine has noticable downshifts if braking lightly, especially if in sport mode.

Originally Posted by Barraman

Hmmmm, now that is a possibility! I have only recently started to use Sport mode. Will drive it in Drive to see if it still does it. Thanks!

And therein lies the beauty of a forum like this!

Problem solved - it doesnt happen in “Drive”, only in “Sport” mode . Its the gearbox downshifting under firm breaking !!!

Cool, the transmission ECU is an adaptive control module in that it learns how you drive. I had a similar clunk befote i serviced the transmission valve body (a whole other saga) but on almost all gears, except 6th to 5th (downshifting), yet it would hold 5th far too long when upshifting.

Put a Sonnax kit though the valve body, new fluid and filter, no more clunks and super smooth shifting.

I still get a noticeable bump from 2 to 1st, but that's inherent to the transmission because 1st is such a high ratio. Also, in sports mode, the transmission will go into 1st, under normal or D mode, it always starts in 2nd