Unfortunately, a LSD was not available for my car, but it really needs one. They were standard equipment on contemporaneous US model 560 SELs and 16Vs.

Don't know what specific market your car was sold in, but I know that certain equipment that was not available either optional or standard on US models was available on models sold in other markets.

A LSD is easy to check. Jack up one rear wheel and DOUBLE CHOCK the opposite front wheel. If you can turn the raised wheel by hand it's an open differential. If it's an LSD it will take a torque wrench on a lug nut to turn and a healthly LSD should require at least 40 lb-ft of breakaway torque.

Duke