190e mercedes , where and how to adjust reverse band ,car goes in drive, but wobbles in reverse,

How do I check the grease in the rear end of my 1991 mercedes 190e

You don't state if it is automatic or manual. For the manual: Looking forwards down the car towards the engine the gear box has three levers on its left hand side. The lever at the rear of the engine is for gear 5 and reverse. From this lever there is a link (metal rod) running back to beneath the gear stick. To adjust this link you need to put the car on a ramp and unclip the link from the gearstick mechanism (three levers side by side). Do not unclip all the links at the same time as it is not obvious which link goes back on which lever!! The clevis on the end of the link can be adjusted by rotating it to either shorten it or lengthen it. There is a locking nut behind the clevis to set the adjustment when completed. Lubricate and clip the link back in place. The 'wobble in reverse' sounds like either a) broken link on the back suspension b) worn subframe bushes c) loose differential mounts (two bushes at the back and one bolt into the subframe on the left/front. If you car is automatic sorry for all this manual stuff, but I would still check out the mechanics of the rear end. Also check out transmission fluid levels, low levels lead to slippage within the torque converter. Another good indication of low fluid is gutless performance coupled with poor fuel economy !!