heard a strange sound coming from under the car at highway speed after driving about an hour. sounds like engine knocking except it was coming from the rear and underside of the car. the sound changed with different throttle settings. traffic was bad so i had to slow down and eventually stop for a moment. when i started forward again the sound was gone. after i parked i looked under the car and noticed the left rear wheel axel boot is leaking oil. there is also a clicking/rattling sound when i back up the car, this is a 84' 300cd. what do you think about this problem and what are the solutions...thanks.

Sound like the CV or Half Shaft are gone.
I would not just replace the boot. Usually need the Axel.
Charlie

if you do in fact need a 1/2 shaft, try a carquest rebuilt. i have 2 in my car and they are sofar performing well.

you could also do a search on 1/2 shafts here as many members have posted on the subject.

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1984 300D Turbo - 231k....totalled 11/30/07 RIP

did some searching on this forum. sounds like i have a bad 1/2 shaft, even if that isn't the source of the noise it still needs to be replaced as the boot is torn. the part new is expensive around $400, the rebuilds are much cheaper but it seems some people have had problems with the rebuilds. i thought i would replace both 1/2 shafts but if i go with the new one i will only replace the one bad one. i'll have to sleep on this one.

them rebuilt locally for about $120 each and they have fine ever since june of last year. If one boot is torn the other is sure to tear soon. It is not a hard or difficult job but while your are in there and have it all apart I think you may as well do them both. You would hate having to take it all apart again next month or year.

thebern

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1982 240D 313,000 (4 speed)
1984 300CD 172,483
1985 German Shepherd Dog -Lacey- R.I.P.11/04/05

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