Good afternoon gentlemen. I have a 95 240 SX (110,000mi 5spd) with a couple nagging problems. My rearend (the cars'

) has started doing a rather havy jolt when taking off or stopping quickly. It's as if it's trying to catch up to the rest of the car. In fact, just lots more squeeks and noises from that area in general.
My other problem is my ac/heater now only work on full blast. Does anyone know if this is a costly fix?
TIA,Wilco