Well, he did say:
"Have an intermittent whining coming from the rear end".

Then he said:
"It's a high pitched whining and it went away when I backed up. ??"

Now maybe I should have asked the 20 questions. like when did this start? how long has it been doing it? low speed, high speed? Is there oil in the Diff? has it been leaking?

We don`t know if it is the diff., could be an axle starting to complain. once the oil is drained, we will maybe know something, is it clear, or have pretty sparkles in it? It could be the pinion bearing/shaft. grab the Diff flange and see if their is movement up/down.

Maybe this is his only car, and he needs it to putz around town to work or to PNP for another rear end. I mentioned no long trips, maybe I should have said, stay off the freeway, no high speed driving.

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

Charlie, I took this to mean he had the option of letting it sit until he had a chance to fix it... Usually if a car is a person's only car they mention it by now.
So, if he has that option.... the safe bet is to try to fix it without driving it.

" yeah, speaking as one who has had a pinion bearing fail on the highway... fixing before it fails is much better option... "-- Vstech

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1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/diesel-discussion/10414-help-i-need-check-stretch.html

http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

evap fin cleaning:

http://www.peachparts.com/shopforum/diesel-discussion/156207-photo-step-step-post-showing-w123-evaporator-removal-1983-240d-1982-300td.html?highlight=evaporator

A/C thread

http://www.peachparts.com/shopforum/diesel-discussion/297462-c-recommendations-mb-vehicles.html

I stand behind my disclaimer:

__________________
I know you think you understand what you thought you heard me say,
But what you think you heard me say, is not really what I ment.


It is how we decipher what we read, and from our past experiences as to how we respond to what we read or hear.

Not every noise is, abandon ship, man the boats before she blows.

ok I`ll shut up before I get torpedoed.

Charlie

__________________
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

Most whining noises from the Diff are low oil and/or excessive wear. I would let it sit until you could at least drain and inspect the oil. Only then can you make an educated decision whether to drive as is or repair.
On a company provided truck our company mechanic forgot to put gear oil back in after a service. I drove it about two miles. Whining, more like screaming. added oil and it worked but never was quiet again. We sold the truck at auction

JB welding a 14mm nut & bolt inside the diff plug didn't work.
Propane torch didn't work. I ended up using Charlie's suggestion and
pulling the entire diff plate off of a 300D at the PNP.
Good thing I took my four foot breaker bar to snap open the diff plug there
before removing the plate. I needed the breaker bar for the 22mm nuts
holding on the diff mount, as well.
I also put in a new differential mount while as it was the perfect time for that.



Thanks Charlie--although it did take longer than 30 minutes to do the job.

The manual says my diff takes 1 litre and that's what came out.
Very dark but no visible metal. Refilled with Lucas synthetic closer to 1.3 litres.

It was getting late so I just took it around the block. No whine so far.

Yeah, I let it sit since I heard the noise, not wanting to take any chances
and carpooled with my wife as the MB is my daily driver.

Hopefully this will be the end of it.
Thanks all for the help.

Jeff

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1984 300SD 300,000 miles--two tank WVO setup
2.88 diff & 500SEL anti-squat rear end