Its very simple, if the car is LHD, gain access to the LHS gear box cover by removing a wheel and protective shield, draing oil before opening a cover which is attached by four bolts.
once the cover is off, you will find one nut (may be 24mm) loose, either replace the nut or tight it. close the cover and replanish the oil. as this is the common defect, hopefully this will work.
Nadir
October 2007