Lifting the car by the transmission cross member could cause the cross member to bend. This might throw the alignment of the tranny/driveshaft out of kilter, possibly damage the flex disk.
Since the car vibrates when the rear wheels are turning even with the engine off, I suspect a driveline component failure. Flex disk, center bearing, alignment or even a bent drive shaft or a combination of all these.
Yes, if the flex disk is now bad, driving it could cause the drive shaft to come loose and beat the tunnel. If that happens, yes, you will have a bang up time when the air bag goes off. And yes, if all that happens, expect the insurance company to scrap the old girl.
I don't think the failure on the 560 I got had anything to do with lifting, it was simply the flex disk gave out at speed. Made a nasty mess of the tranny and tunnel but nothing an able DIYer can't fix
. Current standing: Tranny back together, replacement drive shaft in, tunnel repaired and sealed inside and out, replacement shifter in hand (waiting for installation), blown crash sensor out, replacement waiting to go in and lastly for today - complete set of 15" alloys, with Goodyear Eagles sitting in the back of the truck. Soon as my FastLane shipment arrives I can button up the drive shaft (new flex disk) and install the shifter (shift rod bushings). So close to being able to move her under her own power - too bad I'm going on vacation in two days.
'73 280SEL 4.5 (9/72)- RIP
Only 8,173 units built from 5/71 thru 11/72
'02 CLK320 Cabriolet - wifey's mid-life crisis
2012 VW Jetta Sportwagon TDI...at least its a diesel
Non illegitemae carborundum.