Rear wheel drum splines worn or not

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Tim Splaine
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Re: Rear wheel drum splines worn or not

#16 Post by Tim Splaine »

Not sure of condition of other 3 as the car isn’t at my home.
I will get the guy to take some pictures.
One has missing studs but he can also supply these. Don't know why someone would remove them and if so have they damaged anything?
I may have another option in the UK but would involve removing the splines as the drum is dead. Does anyone know if A splines are the same as B splines ?

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David Jones
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Re: Rear wheel drum splines worn or not

#17 Post by David Jones »

Splines are the same on all the cars. They all used the same VW drive shafts. There were literally tens of millions made.
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Tim Splaine
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Re: Rear wheel drum splines worn or not

#18 Post by Tim Splaine »

Ok Dave. Thanks for that. I may have an option in the UK then.
Cheers, Tim

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Re: Rear wheel drum splines worn or not

#19 Post by David Jones »

You can use the VW swing axle drive shafts from early 50's to 66 all the same length. All VW drums were steel and smaller diameter. I wonder if it is possible to turn down a VW drum and shrink fit it into a Porsche drum bored out to accept it. How does Martin restore drum splines?
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Martin Benade
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Re: Rear wheel drum splines worn or not

#20 Post by Martin Benade »

I don’t think splines get swapped with used ones, I believe Martin’s method is to slightly crush the insert, tightening things up. But ask him.
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David Jones
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Re: Rear wheel drum splines worn or not

#21 Post by David Jones »

I wondered if it were possible as new VW rear drums are about $70 whereas new 356 rear drums are $3k apiece.
Of course replacing the centre would be pointless if the steel braking surface was not perfectly serviceable.
If I had known I would live this long I would have pushed the envelope a little harder.
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Tim Splaine
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Re: Rear wheel drum splines worn or not

#22 Post by Tim Splaine »

Ok something I havent hecked either on my car is the diameters of the linings. What's the minimum. I read from a guy selling some that it is 282mm. I don't have a pair in front of me, but this sounds too big. Or is it?
Thanks, Tim

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Re: Rear wheel drum splines worn or not

#23 Post by David Jones »

282 mm wear limit.
If I had known I would live this long I would have pushed the envelope a little harder.
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Tim Splaine
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Re: Rear wheel drum splines worn or not

#24 Post by Tim Splaine »

Thanks Dave, I maybe able to take a trip up to play with her tomorrow after work and bring one home, whilst checking out the other.
Tim

Tim Splaine
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Re: Rear wheel drum splines worn or not

#25 Post by Tim Splaine »

So what you are saying Dave, is , is it possible to buy a new VW drum at $70 and push out the spline to use in the 356. Is that right?
Sounds plausible and the best solution all round.
Tim

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Re: Rear wheel drum splines worn or not

#26 Post by David Jones »

The VW drum is a cast steel piece, one would have to machine the drum down to a size that could be accommodated by the steel insert of the Porsche drum. That procedure is above my pay grade.
If I had known I would live this long I would have pushed the envelope a little harder.
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Joris Koning
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Re: Rear wheel drum splines worn or not

#27 Post by Joris Koning »

I have no idea why one would gamble with buying some drums from the US unless they come from a reliable source when you can also just contact Paul and Mike @ PRS. I have bought drums in the past where the seller swore the splines were good…. They were not. Only way to really check is by inserting a known good axle and check.
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David Jones
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Re: Rear wheel drum splines worn or not

#28 Post by David Jones »

I agree with Joris, buying used drums from PRS is probably the best option.
If I had known I would live this long I would have pushed the envelope a little harder.
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Tim Splaine
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Re: Rear wheel drum splines worn or not

#29 Post by Tim Splaine »

Ok something I havent checked either on my car is the diameters of the linings. What's the minimum. I read from a guy selling some that it is 282mm. I don't have a pair in front of me, but this sounds too big. Or is it?
Thanks, Tim

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David Jones
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Re: Rear wheel drum splines worn or not

#30 Post by David Jones »

New is 280mm, wear limit is 282 mm.
If I had known I would live this long I would have pushed the envelope a little harder.
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