The Official 356Talk Forum

What does the other side look like? Does it have a generous chamfer?

Yes it does; I don't understand why that wasn't enough, but I find than now, with the washer, there is no loosening of the nut.

Hi, Paul.

Could you please describe the "appropriate washer" that you have installed? Part #?

David the appropriate washer is probably no longer available. There used to be a washer and a nut but with the "B" the washer was integrated into the nut probably because people were putting the washer back on with the bevel out and thereby allowing the drum to come loose. The "B" nut has the washer integrated in to it. If you have still the original style switch to the new style next time you do your bearings/seals.
https://www.amazon.com/EMPI-Zinc-Stock- ... w+axle+nut

Hi, David.

I changed my car over to the later style flanged nut many years ago and all went well, until I had my rear drums reconditioned like Paul. Now I have an issue with the left rear that seems similar to Paul's. I note that Stoddard lists the A car washer, and was curious to know if that is the item that Paul used, and whether he placed it between the later style nut and the hub, or used the early nut as well. Or, was it some other washer that he used? Does the early washer have a deeper chamfer than the later flanged nut?

Examples of rear axle nuts removed from various 356 models.
There was only one Porsche part number for the B and C flanged nuts.

Did you use the additional washer on inside or outside of drum?

Michael Foster

The original nut and washer were a carry over from the VW rear axle and the washer went on the outside of the drum with the bevel facing away from the nut. I doubt your problem is the same as Paul Lima but if you swap the drums from side to side you would find out if the problem was the spline or the axle.

Here is the washer I used: https://www.mcmaster.com/#93162A380 ID is slightly bigger than the OD of the splines, and OD is slightly bigger than the nut flange. Rockwell C38 is plenty hard for this job. It is thin enough that the cotter key goes in without trouble.

Jon, art the two larger integral washer bolts stepped on the back so they mainly clamp on the splined insert and less on the drum? That is what it looks like, which would be the opposite of what solved Paul's problem.

Martin is correct. The problem appears to be that the axle nut was at least partially clamping on the axle spline and not so much on the drum. The washer (which I placed right under the axle nut) guarantees clearing the splines and putting all the clamping force on the drum where it belongs.

I cannot tell from Jon's pictures what is "up" and what is "down". My take on it is that the nut/washer should especially tighten down on the spline insert but maybe that is an optical illusion. And I don't know which part is really supposed to be clamped, so I am probably not correct about anything here.

Is the axel an original or a replacement Sway-a-Way?

Since you mention Martin having worked on the splines, are those inserts still within spec thickness? See below for factory drawing of the spline insert and general drawing of the drum x-section. Note the thickness of 48 plus/minus 0,15 .

Martin Benade wrote:I cannot tell from Jon's pictures what is "up" and what is "down".
My take on it is that the nut/washer should especially tighten down on the spline insert but maybe that is an optical illusion. And I don't know which part is really supposed to be clamped, so I am probably not correct about anything here.

Martin, the hex side of the nuts (top photo) face outward, the flanged side (bottom photo) face the drum.
You're correct, the contact surface of the later nuts is stepped away from the flange, and should only contact the splined steel insert of the drum.

Excellent information, Brad.

Brad you mentioned Sway Away replacement axels. Is there a problem using them? I'm asking because I just replaced my axels on the A coupe and have had a couple of issues.