Volvo Repair: 240 rattle, volvo 1989, control arm bushing

Question
Greetings- I hope you can help- this one has my longtime mechanic stumped.
Volvo 1989 240 GL- there is a rolling rattle that seems to be coming from the front drivers side wheel- but it only rattles when on an uneven or bumpy road. this does not impact the ride or control- but is driving me crazy. My mechanic has replace the front shocks and strut as well as i belive tie rod and has welded other parts only to have the rattle return. he did say something about removing a head or header something...
can you shed any light on this?
thanks so much,
Patti  

Answer
I would check that the engine crossmember is tight where it bolts to the car chassis.other possibility is a bad ball joint.or loos lower control arm bushing where it fits into the bushing holder.I am not sure what he means by head or header.also the heat shields on the exhaust often rattle.