hello,

im in the market to purchase a 300d with 143k miles, and i found one in a dealership 3 hours away from my home.

now i asked the person to take some pics of the undercarriage and this picture in particular caught my attention, he states that the car does not leak but on the picture it shows some sort of concentration of oil in the rear axe, could this be leaking? and how difficult is to fix it?

i am familiar with the engine part of the car but i never got the chance to work on anything else then the engine so my knowledge in the 300d is very basic.

any opinion is welcome.
thank you.

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Looks like a weep of lube from the differential, or could be a leaking boot on a rear axle. Rear axle boot leak = replace the entire axle assembly, not too difficult or expensive. Leaking differential = 3x or more difficult to replace vs. an axle, no idea how much to simply fix a leaking seal, but I suspect that could also be very difficult/expensive.

I'm guessing that it is a very slow differential leak, if at all, and you can simply live with it for a long time. Might also be result of over-filled differential, which burped out the excess from the vent.

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Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC

This is my experience only, so take it with caution.

If the axle or pinion seal leaks then you would find oil stain on the control arms as the oil spins out when car is in motion. Both control arms look bone dry so I would discount the seal. I think the leak is from the back face plate seal. It is simple to fix since you may have to replace the diff fluid. Drain the diff, make sure you can open the fill plug first, remove the 8 holding bolts and reseal with RTV. Refill and you should be good to go.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

Not to dismiss a leaky rear axle/differential, but it seems like the "pumpkin" can sometimes be a catch all for leaks forward of the firewall as well.

Sounds strange, but if you're driving down the road with an oil leak those droplets can get blown back and land on the rear diff housing.

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1974 240D "Boldie" 170K.- New timing chain/freshly rebuilt IP/replaced valve seals/injectors/upgraded stereo/new Bilsteins with Yokohamas/fresh paint and rocker panels plus lots of welds.

Looks to me like the plate on the rear of the differential is leaking, though not badly, could be as simple as tightening the bolts in the plate a little. Usually if the axle seals in the differential are leaking it will throw grease all over the under side which doesn't seem to be happening. The plate on the rear of the diff doesn't use a gasket, just some RTV sealant. I wouldn't worry about it too much if that is the only thing leaking. The pinion seals for the axles aren't too hard to replace. The driveshaft pinion seal is a little more complicated but since the front doesn't seem to be wet in the pic I wouldn't assume it's leaking.

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Every thing looks more or less dry except for the Diff cover seeping some. not a big deal, looks normal for a 143K mile vehicle. the boots look dry from the picture.

what I see would not be a deal breaker for me on a purchase.

There is the vent on the top of the Differential. If it gets plugged up and won`t let the pressure build up from heat, then it could push some oil from around the rear cover. just a matter of unscrewing the vent and washing it out. most all differentials have one.


Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

thank everyone.

i inspected the car this weekend, it turns out that the car had no motor oil, also it did not have a air filter and the air filter cabin was full of oil, the turbo didnt work ...so much going on.

ended up not buying it at all.

here is the ebay listing, it looked promising. Mercedes-Benz : 300-Series Mercedes-Benz : 300-Series | eBay

then again thank you.