Rear Axle Problem

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JERRY LANDES
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Re: Rear Axle Problem

#31 Post by JERRY LANDES »

And yes I used Sway Away axles.

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David Baugh
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Re: Rear Axle Problem

#32 Post by David Baugh »

Thanks, Paul. I'll pick up a couple of those washers to see if it solves my problem, as well.

When I had my drums relined, I also had the splines tightened. As I understand it, the process involve crushing the steel hub. I suppose that could reduce the hub thickness enough to cause the clamping issue. I simply failed to put the two together.
When in doubt .... Gas it! 
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Jacques Lefriant
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Re: Rear Axle Problem

#33 Post by Jacques Lefriant »

Hi Jerry
Sway away axles were not meant to be installed in the VW/split case/356 differential. to make the axle more robust they used better material and increased the diameter by the paddle this may limit the movement of the axle up and down. this is not an issue if you use the Caddrobi diff.
Jon
There also is a flanged nut that VW uses but does no have the generous champher of the Porsche one.
j
 

Brad Ripley
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Re: Rear Axle Problem

#34 Post by Brad Ripley »

Sway-a-Way axles -- I know very little about those but Jacques does. I just wondered if the splined end was a little longer or something different compared to the stock Porsche.
Also, I don't know what Martin does to "tighten up" the spline insert.

Brad Ripley
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Re: Rear Axle Problem

#35 Post by Brad Ripley »

Not to put another drawing up, but it's right in the Workshop Manual, pg R63, which should help to see how this all works. Here's a detail of the nut and the spline interface.
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Rear axle assy detail.jpg

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Vic Skirmants
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Re: Rear Axle Problem

#36 Post by Vic Skirmants »

The Sway Away axles are too fat at the differential end. They are designed to be used with the later VW tunnel case trans. Bigger diff bearing.

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Paul Lima
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Re: Rear Axle Problem

#37 Post by Paul Lima »

Just to clarify the timeline a bit. First, I installed a newly rebuilt 741 transaxle. Second, the discovery that the axle nut was loose after driving only ~100 miles. Third, I assumed the problem was the slinger washer (next to the wheel bearing) being too soft and collapsing. Not an issue. Fourth, I concluded that the looseness of the spline fit might be the problem, and sent the drums to Martin Willis for tightening. The tightened splines made the drums feel right on installation, but again after 100 miles and a check, I found the one problem drum was again loose. And fifth, Martin suggested that the problem might be the axle nut bottoming on the axle spline so that not all the clamping force was being applied to the spline insert/drum. He suggested that this is not an unusual problem and had seen it several times before, suggested the washer. That seems to have ended the loose axle nut problem.

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Paul Lima
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Re: Rear Axle Problem

#38 Post by Paul Lima »

And to complement Brad's picture, here is one I color coded to help me see how it all goes together
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Rear Axle bearing seal 2017-05-21 16-35-15.png

Jon Bunin
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Re: Rear Axle Problem

#39 Post by Jon Bunin »

PaulLima wrote:... And fifth, Martin suggested that the problem might be the axle nut bottoming on the axle spline so that not all the clamping force was being applied to the spline insert/drum ...
Paul, if the axle nut was bottoming on the axle splines, there would be obvious evidence of that on the nut, of contact and damage where contact should not occur.
Examining the nut would have determined if this was happening.
Jon Bunin

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David Baugh
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Re: Rear Axle Problem

#40 Post by David Baugh »

Question: What is the purpose of the washer between the bearing and the bearing spacer? Doesn't seem that it would spin fast enough to act as a slinger.

Several weeks ago, I helped a friend with a seal on his 356C. The washer was missing, so we decided to do the other side, as well. No washer on that side, either.

Dave
When in doubt .... Gas it! 
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Paul Lima
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Re: Rear Axle Problem

#41 Post by Paul Lima »

That washer is there to keep as much oil as possible inside the bearing and axle, and provide a good sealing surface for the o-ring. There are a number of soft metal (VW) washers out there and they will collapse (see pix above in this thread). The Porsche part is very hard; you cannot bend it by hand.

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Neil Bardsley
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Re: Rear Axle Problem

#42 Post by Neil Bardsley »

David Jones wrote: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
I have recently had a issue since to what started this thread. Noise metal/metal coming from the right rear wheel. It went away after I changed the gearbox oil and adjusted the brakes. However, it's come back again after about 2 months of driving. It's most pronounced at slow speed and when turning. I too initially thought it was the wheel rubbing on the body but I checked on the arch/wheel. There isn't any clear wearing on either. The rear right wheel is the only axle nut I've had off. However, I checked yesterday and it's tight. When raised the wheel spins nicely with no noise. There isn't any lateral movement in the wheel. I have the older style axle nut and washer. I didn't notice a bevel on one side so maybe I installed that incorrectly?

Otherwise I would going to try and change the bearing but didn't want to spend $400 on one tool. There must be some alternatives?

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Vic Skirmants
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Re: Rear Axle Problem

#43 Post by Vic Skirmants »

If that washer is on wrong, you will have a tight nut, but a loose drum. Better check it.

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Neil Bardsley
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Re: Rear Axle Problem

#44 Post by Neil Bardsley »

Thank you Vic.

Would buy a kit like this work? I was thinking I should upgrade to the new combined washer/nut style? Plus this way I would have the bearing if the issue? If I understand correctly one of the washers from the VW kit is soft and shouldn't be used?

https://www.ebay.co.uk/itm/Wheel-bearin ... SwiIxZ91Pm

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Jacques Lefriant
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Re: Rear Axle Problem

#45 Post by Jacques Lefriant »

Hi has this issue been resolved 2 other problems can occur 1. the heavy washer #12 in the diagram is missing? or 2. there are VW axles that have much longer splines but that would be immediately apparent.
j
 

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