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Hi have a question about powerflex are they worth buying and if yes wich bushes should i buy first ?
 

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I put power flex lower rear bushes in mine it made ride better and steering more precise along with the 4 wheel alignment. However they were noisy as hell once the silicone grease dried out
 

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I put power flex lower rear bushes in mine it made ride better and steering more precise along with the 4 wheel alignment. However they were noisy as hell once the silicone grease dried out
I had that same problem with the fronts. Sounded like a tramps mattress


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I put power flex lower rear bushes in mine it made ride better and steering more precise along with the 4 wheel alignment. However they were noisy as hell once the silicone grease dried out
I identify with the first part of this, but not the latter. The rear arm movement is not that great and power flex developed the bushes on my car. Then field tested with some of their trusted agents. I recently had my rear wheel bearings replaced on my Q4 and it is incredible how quiet the back end is. I need to do the front wheel bearings soon as they make the car sound like a front wheel drive version.

As I said my initial observations were, one could forget about the back end as it was so well planted and tangibly makes the steering more precise in bends. And to re - iterate, the trailing arms, and in particular the large replacement power flex bush, do not travel very far, so if something is squeaking, I can't see them being the problem.
 

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I identify with the first part of this, but not the latter. The rear arm movement is not that great and power flex developed the bushes on my car. Then field tested with some of their trusted agents. I recently had my rear wheel bearings replaced on my Q4 and it is incredible how quiet the back end is. I need to do the front wheel bearings soon as they make the car sound like a front wheel drive version.

As I said my initial observations were, one could forget about the back end as it was so well planted and tangibly makes the steering more precise in bends. And to re - iterate, the trailing arms, and in particular the large replacement power flex bush, do not travel very far, so if something is squeaking, I can't see them being the problem.
it was 100% the problem with mine as I got some silicone spray in there and the noise went until they dried up again. They defo had grease when installed as I bought the housing with bushes fitted from autolusso and could see the grease betweeen the 2 parts
 

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How many tramps mattresses have you been sleeping on?
Too many to recall. It’s a weekend sport

Back to the squeaking, it has been recognised by many and I recall jabawokjay drilling his arms and inserting a bleed nipple to address the tramps mattress....




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Too many to recall. It’s a weekend sport

Back to the squeaking, it has been recognised by many and I recall jabawokjay drilling his arms and inserting a bleed nipple to address the tramps mattress....




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We are talking 159 here, aren’t we?

Been out and about today again and not a peep. My bushes have been fitted 3 - 4 years and no hint of squeaks.

The large bush’s travel is so little, compared to front bushes and those fitted to 156’s, I just don’t get it!

If I remember rightly, there is a bolt through the central S.S. pin. I could understand it if there was a lot of rear suspension travel, but on mine there just isn’t.
 

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I had front lowers fitted recently by Autolusso. I queried the squeaking after reading about it on here and was told only the uppers had that issue. No problems as yet...
 

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You know that's not true.....if it was just a case of getting better geometry or handling all the manufacturers would all fit poly....but they have to consider lots of other things...cost, comfort, manufacturing ease...and most important NVH....but lots of us will put up with a little more of that to get a sharper handing car. I doubt plastic (poly) bushes are much if any cheaper to make than rubber ones.
 

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I had the poly aka plastic bushes in the lower rear arms on both my 159 for 30k plus and in my Brera for around 20k with no noise or negatives.
Steering felt more precise and the tyres wore evenly, its the upper arm bushes that have the squeaking issue.
 

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You know that's not true.....if it was just a case of getting better geometry or handling all the manufacturers would all fit poly....but they have to consider lots of other things...cost, comfort, manufacturing ease...and most important NVH....but lots of us will put up with a little more of that to get a sharper handing car. I doubt plastic (poly) bushes are much if any cheaper to make than rubber ones.
As a suspension designer I can confirm that your thoughts are rubbish. I have contributed many posts on plastic bushes. The first thing you ought to note is that plastic is much cheaper than rubber so if it worked you know it would be used. The complex bushes in today's cars are designed with many attributes. Sticking in a lump of plastic destroys carefully tested compliance and movement. You destroy self steering, you destroy anti dive, you destroy alignment etc etc. The plastic bush is just something that fits the hole and often not even this is achieved. Squeaking comes from incorrect sizing of the hole which either allows too much movement or too little (it's forced in). Fitting non compliant plastic does not improve handling; it just fools you by making the steering tighter while washing the car out wide because the wheels are not in optimum contact with the tarmac.
Finally, there is not a single manufacturer that fits plastic. And some of those are producing cars that are aimed at track use. If it improved handling they would use them.
 

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That really does sound like a load of theoretical nonsense written by someone who had thought about it a lot...but never actually felt the chalk and cheese difference of the same two cars...one stock and the other polyed. Sharper, faster turn in due to more accurate geometry that stays where it should be. I don't know why you keep saying they are cheaper...polyurethane is about 10 times the cost of rubber and more difficult to shape. It will be noisier and possibly stiffer feeling but a price worth paying for many. Like rubber there are different compounds with some offering a softer compound for street use that, although not holding everything as tight as the harder ones is still better than rubber. Most rally or race cars don't use rubber bushes they use poly...some even use solid metal...the excessive NVH not being much of an issue there!

This is from a poly bush supplier...I know you will say they are bound to be biased but it gets the point across and there are lots of independent features online that day much the same. I realise they are not for you...but they will be on my car (as I've done on cars in the past with absolutely no negative effects) when mine wear out.

Why don't manufacturers fit them from new?

Cost, availability and marketing. Polyurethane, as a raw material is about ten times the cost of rubber plus it is more expensive and slower to process. Car manufacturers buy a lot of components. If Ford decided to use polyurethane bushes in their range of cars they would need to find a supplier capable of making literally millions of bushes a year. There is no company in the world (even EPTG Ltd) who could make those sort of quantities. Cars are all about marketing. As long as the standard rubber bushes work without serious failure for two or three years then the manufacturer is happy. Would fitting of polyurethane bushes make you buy one car in preference to another make? Probably not.
 

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I bought a 159 2.4jtdm 2007 4 years ago with 105k km and it was eating the tyres, lasting about 7-8k km with heavy wear on the inside edge even with rotating them. Got Powerflex front lower rear bushes done by my local indie (about 500nzd/250 gbp all in) and toe adjusted with a touch to positive and they last about 18-20k km now and the steering is better, no squeaks and not too harsh. Done 160k km now.
Ps. great car, power, economy, style, comfort.
 

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To be fair and pre-empt OEs reply!.....most of that the wear reduction will be losing the toe when they did the geometry..the bushes will help of course but the the 159s had way too much toe out from new and many members have similar results on stock bushes...just by changing the alignment.
 

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Yeah, I tried mucking about with alignment but the flex in the original rubber bushes pushed the toe out anyway. It wasn't until I got my guy to put in the poly that the tyre wear improved. I would mention that I have the earlier narrower bushes, so the later wider ones may be slightly better.
 

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The main issue with the standard bushes isnt the material they are made from but that they are void bushes which allow too much movement so with the alignment set correctly or even to a revised setting as soon as the wheel is under braking or acceleration load it moves rearwards and gives a lot more toe out.
This has been discussed many times and although oe is correct in his theory that is assuming that the design and development of these bushes was without error, and we all know that many other parts of the cars had design faults so it is fair to assume that so the bushes may not be correct.
Its a simple case of the poly or plastic whatever you want to call them bushes do improve on a bad design and without any reported downsides.
 

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Just on a point of accuracy...under acceleration you gain toe in ...not toe out...that why most front drivers have toe out as stock...so that it straightens out under acceleration (the driven wheels trying to pull forward).....opposite is true of rear drive cars which are typically set up toe in as the front wheels get pushed back under throttle..
 
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