You can measure from the snap ring groove back to the machined face on the axle with a Machinists Ruler. The rulers normally go down to 64ths of an inch.
See the diagram where to measure.

What you would be doing is measuring the New Axles and comparing them to the old Axle measurements. That will give you an approximation as to if you need different sized spacers or not.

I can't say about Canada but here in the US you can go to any large hardware store and find a small pocket ruler that will go down to 64ths of an inch.

Attached Thumbnails

 

__________________
84 300D, 82 Volvo 244Gl Diesel

Why use 64ths of an inch? These are Mercedes!, and like us in Canada, MB uses the metric system

Two things:
- I can't measure the existing axles while they are still in the car!
- Your diagram doesn't show the measurement needed correctly. Snap ring groove is at the end, not where red arrow points.

Otherwise all good

Actually, we have a pile of used axles at friends place. When next there, I am going to compare the new GSP axles to those. The GSPs measure 64+/- mm from spacer face to the nearest side of the circlip groove.

__________________
Graham
85 300D,72 350SL, 98 E320, Outback 2.5

I can only speak of what I know about and fractional equivalents and decimals can be converted mathematically to any units you desire.

Just like when I did the front wheel bearing end play I used an inch type dial indicator. Later I bought a metric for the sake of convince one the inch one worked.

__________________
84 300D, 82 Volvo 244Gl Diesel

Only shims I have found to be available are 32x45. 32x43 would be better. The outer edge of teh contact face is about 43mm.
Looking at diagram, it does look like a slightly larger diameter would not interfere with anything, but shim would not be fully supported. It is item 27 in diagram. An ID of 32mm might catch on the radius that can be seem in the pic below. Edge could be rounded a bit. I guess.

If nothing else, learning more about the old car

__________________
Graham
85 300D,72 350SL, 98 E320, Outback 2.5

A larger outside diameter shim will likely not be able to pass through the Differential Seal.

__________________
84 300D, 82 Volvo 244Gl Diesel

I have a pile from other cars and mix and match till I find the right spacing. It doesn't hurt anything to run without the shims, but you will sometimes get a clunk out of the rear end during shifts.

Good point. The 32x45mm OD generic shims are same OD as the axle boss, so presumably would just work. But you are right - larger would be a problem unless the seal could be installed on the axle instead of in the diff.

__________________
Graham
85 300D,72 350SL, 98 E320, Outback 2.5

A few moments spent on a bench grinder with a fine wheel can reduce the OD to below the diameter of the seal surface.

May have to do something like that if existing are not right thickness, although 45mm should work.

One thing I found, was that the spacers for the W123 (0.7-1.5mm) are thinner than the ones for the 107 (something like 2.5-3.2mm). Axles otherwise pretty much same.

I did check distance from face that spacer contacts to nearest edge of the circlip groove for my new GSP axles as well as for 4 other original W123 original axles. They were all pretty much the same - just over 64mm. If so, the original spacers should hopefully be OK.

__________________
Graham
85 300D,72 350SL, 98 E320, Outback 2.5

I agree.

__________________
84 300D, 82 Volvo 244Gl Diesel

If shim rings can't be found, or only ones with too large an ID are available, this guy shows how to make them. Of course you need a retired Swiss engineer with a machine shop next door

https://www.youtube.com/watch?v=lGsA_q4guwM

https://www.youtube.com/watch?v=CbtCGEJ9z8I

So, far, I have found some 32x45 shims, but only in large quantities from wholesalers. I don't think we will need any, but did find the videos interesting. Neat way of making them.

__________________
Graham
85 300D,72 350SL, 98 E320, Outback 2.5

G:

1.25" x 1.75" in many thicknesses are readily available in small quantities; these diameters can be adjusted with a die grinder/Dremel tool, and a bench grinder.
The vendors can mail them to you via USPS-Canada Post.

All a bit theoretical now, because GSP axles appear to be same dimension as similar OEs, so original spacers should work.

If I do need them, I would have to buy them in Canada. I just received an oil cooler line that was shipped from Ca on June 25 by USPS! Covid doesn't help.

1.75" OD is good (44.45mm). I don't think I would choose a die grinder to accurately open up 1.25" to 32+ mm in such thin material. There are no doubt other ways of doing it (one in the second video above). I have lathe & mill available next door.

Another factor to consider, is the material spacers are made from. Presume they are hardened steel with a machined surface? Anyone checked to see if they are hardened steel?

Our 32x43 size does not match DIN 988 specs exactly. Maybe they were specially made for MB. However the DIN 32x45 are actually 32.08-32.33 ID and 44.67-44.92 OD which would be good if they could be found in suitable thicknesses. These looked promising until I found that they wanted to charge $57 to ship two packs valued $28 to me by ground!
This company has what is needed, but is in Europe and shows no prices.

That's enough! - May be of use down the road for someone.

__________________
Graham
85 300D,72 350SL, 98 E320, Outback 2.5

Existing spacers worked with GSP axles, so we can call of the search

We hadn't paid attention to the otehr end. There we had to cut the spacer tubes 3mm shorter than they were. Hard to understand why, but only way to get the axles tight in hubs.

__________________
Graham
85 300D,72 350SL, 98 E320, Outback 2.5

Thanks!

__________________
hellodear.in downloadthoptv.com