Fitting annular axles to 300D with isokinetic axles

[Graham]

We will likely be installing GSP annular axles on our 85 300D soon. I am not totally happy about this, but it may be easiest and least expensive way. As I understand it, they should fit. However, I have also read something about problems with fit-up at the diff face.

Can anyone who has done this advise what we might run into?

Should axles be installed in one piece, or separated at flanges first?

PS: I will re-boot old axles as spares.

[Shern]

Not sure what isokinetic axles are (perhaps you mean homokinetic?) but I can tell you about annular. I've never understood the forum reluctance to installing them.
With a cheap Homokinetic axle, you're stuck opening the diff to replace it. Not so with a cheap annular axle. Totally mitigates the risk of using something other than a $400 a side rebuilder.

RE: installation, I encountered no issues.
The spacers already in the diff were adequate. Certainly no need to separate.
The one thing I'd suggest however, is to retorque each bolt connecting the two pieces of the unit(axle to flange?). After a few months of driving mine were almost finger loose. I noticed a thin spray of grease at the axle union. I'm fortunate to have caught it when I did. No issues since, though I do check them periodically.

[Graham]

Originally Posted by Shern

Not sure what isokinetic axles are (perhaps you mean homokinetic?) but I can tell you about annular. I've never understood the forum reluctance to installing them.
With a cheap Homokinetic axle, you're stuck opening the diff to replace it. Not so with a cheap annular axle. Totally mitigates the risk of using something other than a $400 a side rebuilder.

RE: installation, I encountered no issues.
The spacers already in the diff were adequate. Certainly no need to separate.
The one thing I'd suggest however, is to retorque each bolt connecting the two pieces of the unit(axle to flange?). After a few months of driving mine were almost finger loose. I noticed a thin spray of grease at the axle union. I'm fortunate to have caught it when I did. No issues since, though I do check them periodically.

Thanks. Yes homokinetic. (Some call them isokinetic though! Used more for exercising body parts)

What make of axles did you use?

if I understand,
- you re-used the same spacer your homo axles had originally?
- you installed in one piece
- you retorqued each bolt. (using Loctite? What torque?)
- re-used existing diff seals?

I recall you previously used the 3M 5200 that I used. Did it ever fail? Mine has worked well, but there are now new cracks on larger diameter end near inner can where it maybe flexes more. Could re-seal, but seems it is now time for new axles or boots!

[Shern]

Originally Posted by Graham

Thanks. Yes homokinetic. (Some call them isokinetic though! Used more for exercising body parts)

What make of axles did you use?

I believe they were DSS -whatever the brand is here on pelican parts.

if I understand,
- you re-used the same spacer your homo axles had originally?

Yes

- you installed in one piece

Yes

- you retorqued each bolt. (using Loctite? What torque?)

I applied loctite but I doubt it made it through the bore without coming off in the grease. I have m10 bolts, so I torqued to 70nm. The value is different for m12 bolts, however. Info is in this post: http://www.peachparts.com/shopforum/diesel-discussion/405072-annular-axle-seeping.html

- re-used existing diff seals?

Sure did


I recall you previously used the 3M 5200 that I used. Did it ever fail? Mine has worked well, but there are now new cracks on larger diameter end near inner can where it maybe flexes more. Could re-seal, but seems it is now time for new axles or boots!

I did, and where I applied it, it never failed.
The inner can is where I neglected =)

[Graham]

Great - Thanks for help.

I will check if seals are leaking, otherwise re-use if we can't get them locally quickly.

[Frank Reiner]

Originally Posted by Graham

We will likely be installing GSM annular axles on our 85 300D soon. I am not totally happy about this, but it may be easiest and least expensive way. As I understand it, they should fit. However, I have also read something about problems with fit-up at the diff face.

Can anyone who has done this advise what we might run into?

Should axles be installed in one piece, or separated at flanges first?

PS: I will re-boot old axles as spares.

The great installation advantage of the annular CV-joint axles is that they can be separated.
The inboard stub axles are first installed into the center section (diff), the end play checked and corrected if necessary, the rear cover reinstalled, the mount re-attached to the chassis, and the center section re-filled with lube.
The outboard sections (with both CV-joints) are then installed in the wheel hubs, and the inboard joints bolted to the stub axles.
With one-piece axles they must be compressed ~ 3" (or more) to clear the splines for removal or re-installation.
With two-piece axles they need be compressed less than 1" for R&R.

[vwnate1]

You'll need to remove the old shims from the inner ends of the old axles .

I too had the damned inner CV joint come loose whilst driving, I was dm,ned lucky that it fell apart as I was coasting to a stop light .

I searched lots of junkyards until I found original German annular axles and re booted them at home using the factory boot kits .

[Graham]

Originally Posted by Frank Reiner

The great installation advantage of the annular CV-joint axles is that they can be separated.
The inboard stub axles are first installed into the center section (diff), the end play checked and corrected if necessary, the rear cover reinstalled, the mount re-attached to the chassis, and the center section re-filled with lube.
The outboard sections (with both CV-joints) are then installed in the wheel hubs, and the inboard joints bolted to the stub axles.
With one-piece axles they must be compressed ~ 3" (or more) to clear the splines for removal or re-installation.
With two-piece axles they need be compressed less than 1" for R&R.

Thanks Frank. Installing stubs first is what I 'thought' should be done, and is why I asked. It seems quite a number of DIYers haven't done that and perhaps that is why the bolts come loose? The manufacturer perhaps assumes they will be taken apart for installation, so doesn't torque them or apply Loctite at factory?

Another question comes to mind. Original boots lasted 30 years, but it seems aftermarket ones may start cracking after 5 or so years. Seeing it is relatively easy to change boots on the annular axles, it would be nice if the OE boots would fit. Maybe that is too much to ask for

Has anyone compared the diameters of the Chinese (GSP in my case) with those of the OE homokinetic or Annular axles?

[Graham]

Originally Posted by vwnate1

I searched lots of junkyards until I found original German annular axles and re booted them at home using the factory boot kits .

This is something I am "thinking" about when time comes to re-boot my existing axles as spares for 107 & 123.

But they are homokinetic, so it seems they would need a can removed, one joint pressed off, boots installed, joint reinstalled and then new can crimped on.

Anyone here done this and documented it?
Anyone have a picture of a crimping tool that has worked?

I met one guy that had done at least 3 cars this way, but I have lost touch with him. I think he used Kent's method.

[Shern]

Originally Posted by Frank Reiner

The great installation advantage of the annular CV-joint axles is that they can be separated.
The inboard stub axles are first installed into the center section (diff), the end play checked and corrected if necessary, the rear cover reinstalled, the mount re-attached to the chassis, and the center section re-filled with lube.
The outboard sections (with both CV-joints) are then installed in the wheel hubs, and the inboard joints bolted to the stub axles.
With one-piece axles they must be compressed ~ 3" (or more) to clear the splines for removal or re-installation.
With two-piece axles they need be compressed less than 1" for R&R.

Whoops...

[Graham]

Originally Posted by Shern

Whoops...

Not to worry I guess the Chinese don't supply instructions But you dodged the bullet anyway!

I do like the idea of installing the stub first. That allows end play to be checked more easily. Then bolts to be torqued an Loctited.

I also think I will put in new seals. Might as well as they don't cost too much.

[Diesel911]

Originally Posted by [COLOR=red

Shern;4068018]Not sure what isokinetic axles are (perhaps you mean homokinetic?) but I can tell you about annular. I've never understood the forum reluctance to installing them. [/COLOR]
With a cheap Homokinetic axle, you're stuck opening the diff to replace it. Not so with a cheap annular axle. Totally mitigates the risk of using something other than a $400 a side rebuilder.

RE: installation, I encountered no issues.
The spacers already in the diff were adequate. Certainly no need to separate.
The one thing I'd suggest however, is to retorque each bolt connecting the two pieces of the unit(axle to flange?). After a few months of driving mine were almost finger loose. I noticed a thin spray of grease at the axle union. I'm fortunate to have caught it when I did. No issues since, though I do check them periodically.

I am not following your logic here. Since he previously removed the stock homokinetic axles the Differential is already opened. Also the new annular axles may need different spacers to set the up properly.

Once the annular axles are properly installed you will not need to go into the Differential to remove the axles as you can leave the flanges installed.

The reluctance to use the Chinese annular axles is because unless you remove the bolts and install them with a thread locker like Loctite they often come apart on the road some where.

The other issue is will the GSM annular axle flanges fit other manufacturers annular axles. There is no guarantee of that.

[Diesel911]

Originally Posted by Graham

Thanks. Yes homokinetic. (Some call them isokinetic though! Used more for exercising body parts)

What make of axles did you use?

if I understand,
- you re-used the same spacer your homo axles had originally?
- you installed in one piece
- you retorqued each bolt. (using Loctite? What torque?)
- re-used existing diff seals?

I recall you previously used the 3M 5200 that I used. Did it ever fail? Mine has worked well, but there are now new cracks on larger diameter end near inner can where it maybe flexes more. Could re-seal, but seems it is now time for new axles or boots!

If you got new axles direct from Mercedes reusing the old spacers does not guarantee a fit.
On the Chinese axles people have in some cases slid on the spacers and found that the spacers will not go up flush aging the housing as they are supposed to due to the way the axle was machined and it hanging up on the inside diameter of the Spacer.

You won't know till you get your axles and see.

[Graham]

Originally Posted by Diesel911

If you got new axles direct from Mercedes reusing the old spacers does not guarantee a fit.
On the Chinese axles people have in some cases slid on the spacers and found that the spacers will not go up flush aging the housing as they are supposed to due to the way the axle was machined and it hanging up on the inside diameter of the Spacer.

You won't know till you get your axles and see.

I don't fully understand how the stub axles hang up on the spacers.Have you had this experience yourself? Friend who is helping me with this has a lot of old axles with spacers, so perhaps we can at least try one on new axles before pulling the axles out of my car. Maybe they need to be reamed out a little?

So far as thickness is concerned, VSTech said at one time that the spacers match the diff housing and that the axles all have the same insert length. At least with MB axles. My concern, is that after installing the stub, we may decide we needs different thickness spacers. Wonder how easy those are to get! They come in 9 sizes from 0.7mm to 1.5mm in 0.1mm increments. They may be common to a number of cars, but I get the feeling they may also be 2+ weeks delivery from Germany If lucky, some of the old ones may work. Or we will have to have them made or ground down.

A lot of owners have exchanged axles, so it can't be that bad.

[vwnate1]

I buy the annular boots from the M-B Classic Center, you have to be careful to get the boot kit without the crimp on cans .

The narrow clamps they include are tricky to install even with the correct tool .

FWIW, I bought and am still using the cheapo $10 clamp tool although a dull pair of dykes works fine .