2.47:1 or 2.88:1 Axle for 116.120: - Page 4 - PeachParts Mercedes-Benz Forum

Doktor Bert · #46 06-02-2011, 02:20 PM

Quote:

Originally Posted by DeliveryValve

Lots Of technical Data..

Thanks for this. very, very much appreciated!!!!!!

Doktor Bert · #47 09-29-2012, 11:57 AM

Quote:

Originally Posted by DeliveryValve

Yes with the seal, and 116 and 126 axles interchange. You should be able to use either the 116 or 126 mount. You may have to flip it in order for it to work.

Ok, have the 126 differential but don't want to undertake this until I have a complete understanding of what I need to make the swap.

YOKE: This is easy. I have one and the shop has the socket. Set preload to 8/10 in/lbs. Done.

AXLES: All I have are W116 axles (from my 116) will they work, or not???

SEALS: To use 126 or 116 seals in the 126 2.47 differential??? From what Delivery Valve wrote, I assume that I will put W116 axle seals in the 126 Diff???

Sorry to ask so many questions, but being this is my sole daily driver, I need to work this out carefully before I pull it down.

Regards,

Robert

Stretch · #48 09-29-2012, 12:18 PM

What are the part numbers stamped into the differential casings?

A quick look on the Russian EPC on EverythingBenz - Mercedes-Benz Forum and Web Search Using Google shows that a common part number for the casing is 123 350 22 20 <=

Here's a screen shot for the W126 300SD (first gen!) look for part number 10 in the picture

And here's one for the W116 300SD this time the casing is part number 11

If you have the 123 part number on both of your differential casings I reckon you've got a better chance of cross compatibilty

Doktor Bert · #49 09-29-2012, 01:37 PM

Will check later today. Thanks!

Doktor Bert · #50 10-04-2012, 10:49 PM

Ok,

My 2.47 housing is marked 126 351 10 01 and appears to be of the correct, external configuration for a W116, in terms of the mounting points. The axle flanges, part #83 in the above diagram, are marked with a '126' part number and this differential does NOT have the counterweights, or large 'rings' that I have seen on some differentials. The axles at the diff are small in diameter.

The yoke is also rather small, measuring only about 3-3/4" center to center.

This would seem to be the diesel style yoke, would it not????

As I recall, I was told to simply knock '116'

Thoughts??????

Stretch · #51 10-05-2012, 08:31 AM

I can't tell with this Russian EPC what the difference between these differential housings is.

The 2.47 diff seems to have been fitted to the 380SEC and 500SEC models 126.043 and 126.044 chassis. I'm not sure if it was fitted to cars with smaller engines - I don't think so though...

I think you're probably going to have to "suck it and see"...

Is there a noticable difference in weight between the two differentials?

Could one be made from aluminium? (I'm just thinking about 126 SEC aluminium trailing arms - wild guess)

Stretch · #52 10-05-2012, 08:38 AM

Oh I forgot to mention about axles. In the W123 FSM there's a list of how much oil should be put in each axle can when you rebuild them. Some of the 107 / 126 / 116 models have a larger oil quantity - but not all of them. I think (and I'm only guessing at this 'cos I haven't been able to confirm it yet) that more oil means bigger axle can.

Taking this one step further - if you know from which chassis the differential came from you have a bit of a guess (based on my assumption - eeek!) to whether you should have a large axle can or a small one...

...er perhaps!

(Sorry this is all a bit up in the air - there are lots of assumptions here - but I'm trying to think of a solution!)

cho · #53 10-05-2012, 08:50 AM

Quote:

Originally Posted by Army

The 2.47 diff seems to have been fitted to the 380SEC and 500SEC models 126.043 and 126.044 chassis. I'm not sure if it was fitted to cars with smaller engines - I don't think so though...

I think you're probably going to have to "suck it and see"...

Is there a noticable difference in weight between the two differentials?

Could one be made from aluminium? (I'm just thinking about 126 SEC aluminium trailing arms - wild guess)

correct

2.47 was reserved for gassers SEC,SEL..... 2.24 was the
also version present in gen2 (I still have mine

) 2.88 was first diesel diff later
bumped to 3.07.

in due my search for proper diff I have not seen any aluminum one but then again...who knows....

other bloke that converted his SEC to diesel (over here) has gen 1 car and he went with w123 diff (3.46 and 617 non turbo as I recall...) with no major readjustments......

.

Frank Reiner · #54 10-05-2012, 12:42 PM

For purposes of distinguishing between the two diffs that are the subject of this thread, we need to understand that they are identified by the diameter of the ring gear. The 2.47 has a ring gear diameter of 210mm, the 2.88 has a ring gear diameter of 185mm. All other dimensions of the two series are proportional. Hence, the 185 is narrower than the 210, and the axle shafts for the 185 are longer when used in any given chassis. Further, Gen 2 W126 inboard CV joints are of the bolt-on "Lobro" pattern, while the older style MB tripod joint was retained at the outboard ends. Flex discs are of different diameters. There is, however, an area of commonality; the mounting bolt pattern to the sub-frame, and the rear mount. Quick identification can be made by the location of the vent; the 210 vent is on the main casting, the 185's is on the rear cover.

Doktor Bert · #55 10-05-2012, 02:48 PM

The yoke is also rather small, measuring only about 3-3/4" center to center.

This would seem to be the diesel style yoke, would it not????

Frank Reiner · #56 10-05-2012, 06:46 PM

Dr. Bert:

The yoke that you have just mentioned is used on all 185mm diffs; it is common to all 4,5, and 6 cyl. applications 114/115, 116, 123, 126, and quite likely some 124 and later applications.

Stretch · #57 10-06-2012, 03:24 AM

Quote:

Originally Posted by Frank Reiner

Dr. Bert:

The yoke that you have just mentioned is used on all 185mm diffs; it is common to all 4,5, and 6 cyl. applications 114/115, 116, 123, 126, and quite likely some 124 and later applications.

So in other words - are you saying there's no such thing as a diesel yoke?

Stretch · #58 10-06-2012, 03:31 AM

Quote:

Originally Posted by Frank Reiner

For purposes of distinguishing between the two diffs that are the subject of this thread, we need to understand that they are identified by the diameter of the ring gear. The 2.47 has a ring gear diameter of 210mm, the 2.88 has a ring gear diameter of 185mm. All other dimensions of the two series are proportional. Hence, the 185 is narrower than the 210, and the axle shafts for the 185 are longer when used in any given chassis. ...

Do you know if there is a relationship between the length of the axles and diameter of the axle cans?

Quote:

Originally Posted by Frank Reiner

... Further, Gen 2 W126 inboard CV joints are of the bolt-on "Lobro" pattern, while the older style MB tripod joint was retained at the outboard ends. Flex discs are of different diameters. There is, however, an area of commonality; the mounting bolt pattern to the sub-frame, and the rear mount. Quick identification can be made by the location of the vent; the 210 vent is on the main casting, the 185's is on the rear cover.

Now there's a fantastic tip!

Doktor Bert · #59 10-06-2012, 10:22 AM

I spoke with John, who originated the W116 Dif into W126 thread, and he cleared up a few things for me.

Doktor Bert · #60 10-06-2012, 10:23 AM

Quote:

Originally Posted by Frank Reiner

Dr. Bert:

The yoke that you have just mentioned is used on all 185mm diffs; it is common to all 4,5, and 6 cyl. applications 114/115, 116, 123, 126, and quite likely some 124 and later applications.

Good news here as this yoke should be a direct bolt-in for my W116 Diesel flex coupler.