I now have around 150 miles on my freshly (last year) restored '71 240.  The differential seems quite noisy so I checked the oil level (finger tip reaches oil), then drained it.  No sign of metal filings or debris on the magnet.  I drained it into a four-litre ice cream pail and it only filled it to 15% capacity.  I put in new hypoid lube, but in a 1 litre bottle I've still got 700 ml left with the diff filled right up to the edge of the fill plug.  the FSM says it takes approximately one litre, or .21 gallon.    Just to make sure the oil wasn't all backed up in the diff casing, I left the rear of the car on jack stands and lowered the front.  Very little difference.  I've still got well under half a litre in the car.

I see there was some discussion on this topic in 2011, and people emphasized that actual capacity can vary depending on casting irregularities, but in the case of my car, the difference seems somewhat greater than a casting variation.  Any thoughts?
 

Thanks,

My R200 took almost three litres...

My R200 took almost three litres...

 And that was before you found the leak!? :P 

Seriously though - that’s quite a lot!!

 

 Here’s a screen shot of the FSM

 

 

It was a bone dry CLSD from an 83 so that might be why.

I’ll have to go check what I wrote down.

Stole a measuring cup from Mama.  What I drained from the seemingly full diff was 16 fl. oz = .47 litre.

I have no idea where to put the other .53 litre.  

8 hours ago, Richard McDonel said:

Stole a measuring cup from Mama.  What I drained from the seemingly full diff was 16 fl. oz = .47 litre.

I have no idea where to put the other .53 litre.  

That is really strange, quite often when you empty the diff there will be be far less than a litre because over the years it splashes out of the plastic breather cap on the top of the cover but not being able to get that full litre in is pretty weird I think.  The only way you are going to solve it is to unbolt the cover and have a look, The paper gaskets are cheap and still available but something like Permatex gasket maker work just as well. Hard to believe casting irregularities could take up half a litre of space.

10 hours ago, wheee! said:

My R200 took almost three litres...

That's because you have that gorgeous finned cover with all the extra oil capacity.

 

Oops I completely forgot about the extra capacity of the cover.

 
Oops I completely forgot about the extra capacity of the cover.

Is that the AZC kit? Looks good.

AZC with TTT LCA’s

AZC with TTT LCA’s

Thanks, very nice.

Hey guys,

What socket are you all using to get off the fill plug? I cant seem to find one that i can fit properly as the plug is square not hex and also it hits the moustache bar.

Also is it normal for the plugs to be this far out?

 

thanks

 

Ash

I cheated and filled through the breather.