i have a 230te estste 1991 the problem is that i keep getting engine oil in the hydrolic suspension tank i know this as i have drained it off back down to empty after doing this within a week the oil light is back on on the dash and the suspension tank is full i cant see how it is happening would like to know how the oil can get into the tank .refrence it being lumpy it just feels like there is too much air in the tyres have set them to the correct pressure and that dosnt make any difference even tried a little less but no difference is that better info for you ps it rear hydrolic suspension the front are springs amnd shock asorbers