Hello,

Few years ago my steering wheel started to shake/woble under breaking at higher speed. As the time went by it started happening at lower speed as well. Originally I had 300 mm discs, changed to 320 mm from ST. The problem was still present.

Last summer I changed my front and rear discs and front and rear break pads. Everything from ATE was installed. In first few thousand km's everything was fine, but then it started again.  I haven't overheated them or anything. Upon inspection, my mechanic says that everything is in order, but the problem is still there.

P. S. The steering wheel also vibrates at highway speeds (100 km/h and more). The tyres are brand new, the wheels are balances, the allignement is done.

Any help in the right direction is appreciated.

Sounds like a slightly sticky caliper.  Worked fine after it was disturbed, but is now becoming restrictive again.  Were the pads all worn evenly?

 

I think they were worn evenly. Can I check on sticky caliper by just removing the wheel?

Not an easy visual check unfortunately.  If you can get a brake roller test done at an MOT station, the results will show if you're getting an even brake application as well as any binding when released.

Years ago I had a wheel wobble and it turned out to be water in a front tyre making the balancing ineffective. Spinning the wheel, I could hear the water inside.

it must have come from a contaminated air line.