What might be the problem?

What causes single knock sound “only when braking” especially in low speed 20-30kph…Few weeks ago i was at the gaurage and mech did some work on tie rod and fix it back. We also changed arm bushes and the brake pads. What might be the issue?

Watu wa subaru

My humble DIY guide
Were the pads properly greased? Were they genuine? If you ain’t going to Vasha kesho, tear apart the whole front suspension tafta pole pole esp that part that you were changing those few weeks ago, the tie rod and arms et al. If Nyuma ni drum, jioshe vizuri, scrub with sandpaper, bleed them if you must, you should notice Handbrake itakua ngumu at first, but i believe the problem should be resolved.
Lastly go for Wheel alignment and balancing, also ensure pressure ni as recommended.
Next time give more details, Car make/Model year bla bla bla

I experienced this once some time back after changing the bushes. Mech aliniplay. Hakuchange bushes. He simply took the new bushes I had given him (probably sold them) and put some funny rubbers hapo. Thats the last time I used him

Angalia hapo kwa bushes

What model? Check stabilizer bushes, if your Jalopy has the tire attached below, angalia kama imekazwa properly, and drive with the mech askize.