Ford Transit Custom 2018 knocking issue

[ihux]

Hi, I am currently enduring a knocking sound from my van’s front and rear arches when I drive over any uneven surface such as bumps, however if I was to lightly apply the breaks when travelling over the uneven surface the knocking does not seem to occur.

I have taken my van to a ford garage and it was booked in for a steering rack replacement however when it was on the ramp they found no fault with the steering rack of which they had originally identified.

I would greatly appreciate any feedback on this matter, thank you.