I've got a new steering rack and my steering and/or general front end handling is getting worse now with intermittent steering wheel vibration on highway and heavy vibration while braking - is there anything in particular I should be looking for? I'm going to jack up the car and crawl under there this weekend while its sunny and warm out.

Complete front-end brake job & new steering rack within the last 12 months.

I am planning on ordering a complete poly bush kit for the front end anyway to match my new rear racing spec bushings/cage mounts but it wasn't a priority until this recent issue.

 

Some things to check:

• Brake rotors warp very quickly. I have had recent experience of a friend's car with brand new ones, fitted to less than 1 thou runout at the rim, warping and juddering after 2000 miles. Check them for runout.
• Check the pads are seated properly and wearing evenly
• Check the wheel bearings are adjusted up properly
• Balljoints can go home very quickly too. Carefully check top and bottom and the ones on the steering arm/rack ends. Check for tightness and the actual ball not having play in its socket
• Check toe setting and wheel balance
• Check also that the camber shins are in the top wishbone/balljoint fixings. If a garage did this work they might have lost them. If any have been left out, put one thick and one thinner one each side of the balljoint as a starting place. Even one of the four missing can produce steering oddities as I recently experienced myself.

Even a loose rack will not per se cause juddering of the wheels; but obviously the fixings and rack centralising via the centralising hole must be checked when the alignment is checked.
Good luck.