Volvo Repair: Wheel Vibrations and AC, wheel bearings, r 134

Question
I have a 1991 940se, and every time I press on the brakes the car starts to vibrating. What would cause this kind of result. Also, is it a good idea to convert from R-12 to R-134, and how would you do it.

Thank you

Answer
The pulsing effect you feel in your brake pedal and steering is probably due to your front discs.Over time they wear and distort,causing uneven braking...if you're doing the job yourself you should check out your wheel bearings and tie rod ends.....any play in these systems causes vibration...
be sure to check caliper to see if it works well....also make sure pads are free fitting in the caliper.

as far as a/c work....you need reclaiming of old and vacuum out system ...add new 134a...don't even think about doing this job...pay the 50 or $75 for someone else to do it.