Hello Habib,

That doesn't at all sound good. Have you checked the trans fluid level? Is the fluid pinky or foamy? If it's doing this while stationary and only in reverse then strikes me as an internal transmission problem. Maybe something worn out and starting to seize like a bearing. This is an automatic? Mileage on the car? Used for towing? Is it different/worse after driving a few miles? When was the last time the transmission was flushed? Synthetic fluid? Last time the pan was dropped to clean/replace the trans filter? If it was doing this only in motion then a bad driveshaft u-joint and/or center support bearing would be the main suspects. Broken transmission/engine mounts can make engine clunking and shuddering worse, but unlikely to be the source of your problem. Not a lot of people following here these days what with website availability problems, so consider reaching out on other forums like turbobricks and Volvo Facebook groups. I'd drain and drop the pan, looking carefully for grey sludge indicating metal wear, replace the trans filter, do a thorough trans flush and use synthetic of the recommended type, crossing my fingers that helps.
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now