stamp on differential case

[1mastertech]

Over the past 12 months I've completed a bumper-to-bumper mechanical restoration of a 66 230SL.  The standard final drive ratio should be 3.75:1.  I believe that the whole rear axle in this car had been switched but I can't determine it's origin.  The (only) number stamp on the differential case is "4/10".  That's 4/10, not 4.10 (if there ever was a 4.10).  Does anyone know what model (sedan?) this rear axle came out of, or was this a special rear axle for the 230SL?  EPC says there were 4.08 and 3.69 options but that 3.75 was standard.

[Benz Dr.]

Some of the fin cars like 220Sb had a 4.10 rear axle ratio. Good for pulling out stumps or moving big rocks.

[1mastertech]

Thanks for the reply.  I'd like to look this up on EPC.  You're thinking that this rear axle came from one of the W110 cars?   Which 110 (W110.).  I'm surprised that everything appeared to fit so well.  (same track, etc.).  Any idea why MB used the convention of the "/" rather than a decimal point?

[66andBlue]

There is an axle for sale on eBay with this diff ratio, apparently from a 190SL:
http://www.ebay.com/itm/171152409240

EPC says there were 4.08 and 3.69 options but that 3.75 was standard.

This is somewhat misleading since, for example, the 4.08 ratio was standard for most cars with automatic transmission exported to the USA.

[ja17]

The axle assembly for a 190SL is different in many ways. Most noticeable is that it has no provision for a compensator spring like the later swing axles.  I think the 4:10 ratio was used in some of the W110 diesel finback sedans of the era.

[1mastertech]

Interesting information.  So this 4-speed manual  66 230SL might actually have a rear axle from an automatic export 230SL (or some W110 diesel?).  Too bad that MB wasn't using Data Cards back then.  And that a Master Inquiry, thru MBNA, for that era doesn't exist either.  Must be some internal documentation at Mercedes that lists the equipment installed with each VIN.  A Master Inquiry, for instance, shows the port of entry, the selling dealer, all warranty programs, all dealer service, component ID, and more.  A useful source for verifying drive train swaps, defective odometers, etc.

[66andBlue]

...  Too bad that MB wasn't using Data Cards back then.  ...

How did you arrive at that wrong idea?
See info on data card: http://www.sl113.org/wiki/DataCard/DataCards
So call the Classic center in Irvine and get the vdc for your car.
Also note that the 4/10 differential was never installed by the factory in any W113 car. If your car has one then it was done by a previous owner.