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D2 - Axles, Brakes, Suspension and Steering Brakes, Springs, shocks, steering racks, steering columns, suspension arms, wheel hubs etc.

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  #21  
Old 16th September 2019, 11:12 AM
MikkiJayne MikkiJayne is offline
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Well, these bushes are officially all gone now. None left in the UK, at the factory, or at Tradition

Time to talk to Fibet about making them...
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  #22  
Old 1st November 2019, 04:42 PM
spannerrash spannerrash is offline
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Does anyone know the difference between these two parts?
4D0 505 171L
4D0 505 171H

I have a genuine set of both In preparation for my rear suspension refurb and they look identical apart from the part numbers.

Just wondering if we can't get hold of 171L any more, can 171H be used instead? Assuming we can still get hold of them, haven't looked yet.
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  #23  
Old 1st November 2019, 04:46 PM
MikkiJayne MikkiJayne is offline
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The rubber inside them is a different shape as they move in slightly different ways. One of them is almost solid, whereas one of them has a bit of a recess in the centre to allow more movement, although I can't remember which is which.

I don't think there are any of either of them left now.

Curiously the C5 A6 has almost identical bushes with steel shells. It might be possible to use these instead, but there's only a year left of C5 parts so it doesn't help that much.
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  #24  
Old 1st November 2019, 05:00 PM
spannerrash spannerrash is offline
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Well done MJ, absolutely correct.

I had them both in my hands and didn't even see that.
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  #25  
Old 1st November 2019, 05:17 PM
spannerrash spannerrash is offline
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4D0 505 171H (the one with less rubber) is fitted into the rear wishbone. 171L fitted into the rear hub.

A strange question, I bought a pair of refurbished rear wishbones from ebay. de with new genuine bushes already fitted. I thought this would save time and also save the (hard to get) bushes I already have for future needs.

Problem is, they have fitted 4D0 505 171L (the one with more rubber) into the wishbone.

Is this worth a try, can anyone see any problems?

Or, should I just swap them for the correct ones?

Thanks Frank
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  #26  
Old 1st November 2019, 06:42 PM
MikkiJayne MikkiJayne is offline
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That's rather disappointing since its unlikely you'll get them out without destroying at least two of the four

I've often wondered whether that tiny difference is really that important or whether its just engineers nerding out a bit. The two joints do move differently though - the outer hub joint primarily rotates in a single axis along the joint. The wishbone joint rotates along its axis, but also in an arc perpendicular to its axis - you can see it if you move the wishbone up and down with the bolts loose. I think this arc is the reason for having less rubber in those inner bushes, so they can twist in a second axis.

From an engineering standpoint, having the all-rubber bushes in there would mean less compliance in the bush therefore it would increase the load on the aluminium housing in to which it is pressed. Whether or not that increased load would have any measurable impact is purely conjecture until someone tests it!
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  #27  
Old 2nd November 2019, 07:36 AM
spannerrash spannerrash is offline
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The picture below is of a second hand rear subframe I bought this summer as a spare. I think it demonstrates MJ's point of how the 171H Bushes (the ones in the bottom of the picture) would have to be more flexible. The fact that the two sets of bushes don't run perpendicular to each other means that one set or the other is going to have to flex in a side to side motion a little. As MJ has already stated.

My concern, if I were to fit the 171L bushes is that they would resist this movement more strongly (again, as MJ has already stated) but I suspect this would put extra strain on the subframe brackets that hold the bushes in place. This may cause it to flex. Not a good idea on a 17yr old subframe.

This is all just opinion and theory but I don't think I want to be the first one to try it out.

The Re-manufactured wishbones I have were only £200 (including the new bushes) and second hand wishbones are quite easy to come by. Consequently It may be worth cutting the hollow wishbones apart and trying to save the bushes. It seems at the moment that the bushes alone are worth more than my complete wishbone (with wrong bushes fitted) and are much harder to get hold of.

Or do I just fit the correct bushes and have done with it? I'll give it some thought.

What do you folks think to the second hand subframe by the way? I thought this was in amazing condition given its age. Only £150 delivered and came from Italy. I guess the donor car must have spent it's life in a dry climate.
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  #28  
Old 2nd November 2019, 09:11 AM
MikkiJayne MikkiJayne is offline
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You might be on to something, sacrificing the arms to save the bushes. Like you said, the arms are easy to get, the bushes impossible.

The subframe looks a damn sight better than most UK ones I've seen The subframe bushes are also NLA now so added bonus if they are still good.
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  #29  
Old 2nd November 2019, 09:42 AM
spannerrash spannerrash is offline
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Subframe is actually from a none s8 car (not really sure what engine size) so the bushes were wrong for my car.

I have already removed them and managed to get a full set (two different part numbers front and rear) from the USA.

I won't fit them yet until I'm sure I will need to use it.
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  #30  
Old 2nd November 2019, 10:19 AM
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moltuae moltuae is offline
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That subframe certainly looks to be in good condition ... but I'd give it a coat of POR-15 before fitting it to keep any rust at bay.

If you need to replace the rear diff support bracket bushes by the way, while the D2 bracket (4D0599285) is NLA, a new/good D3 bracket (4E0599285) should be easily obtainable, and is a direct replacement (as I found when I replaced my rear subframe a while ago).
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