I have recently bought an '88 420SEL for my daughter; while it had only 75,000 miles and had not been driven much in the last few years (a grandparents' car), it did have a creaking sound in the front when going slowly over bumps. I have had the various joints lubricated and replaced all four shocks with OEM Bilsteins. The creaking is much lessened, but now I am getting a mild bumping sound ("budubba, budubba")when applying the brakes on a coasting stop, going slowly over speed bumps and on low speed turning. The noise does not appear on harder braking. Any suggestions would be appreciated - is the caster support rod joint the culprit?