I took my car (a '93 bmw 325i, 151K miles) to get serviced. I had all fluids changed, and when i drove out, there was a bit of a intermittent thumping sound in the rear center of my car. It doesn’t happen all the time and appears to happen only when I am in 1st gear, when I turn while in 1st gear, or while I am going backwards and turning in 1st gear.
Does anyone know why this might be happening and if it will be expensive?
Did this start immediately after you had it serviced, if so I would take it back to them ASAP? Are you sure they refilled the differential fluid?
Also, have then check the u-joints on the driveshaft. After 151K, they may be worn out.