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I'm not a huge fan of urathane but I'm also not a huge fan of rubber, thats why I went all metal and bearings on my other car.
 

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Thanks for the info Peter!
 

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Discussion Starter #4
I'm not a huge fan of urathane but I'm also not a huge fan of rubber, thats why I went all metal and bearings on my other car.
I hear you. I know of only a couple of sources for aluminum subframe and diff bushes for the E39 M5. One is a guy on this board across the pond who wanted a pretty penny for them (well over $1k) and custom through Bob Kearns. According to Bob, the first version of the mounts were difficult to make and even more so to fit, so I know he is revising them. If I had my druthers, I'd be using aluminum rear diff mounts (I already have an aluminum front diff mount) and the 95A subframe mounts. But for now, it's Powerflex black all around!

Separately, I'll be interested to hear if anyone thinks the poly bushings for the rear arms are worthwhile. (Cue for Rob to commence a polemic against stiff and solid bushings and for Mike Hilal to accuse me of trying to create a 3000 lb. vibrator).

--Peter
 

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Once again Peter I am starting to question you commitment.

First, bushings are for Camrys not race cars and second you can't put a price on performance (and I rally mean "you") :rofl:
 

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Discussion Starter #6
Once again Peter I am starting to question you commitment.

First, bushings are for Camrys not race cars and second you can't put a price on performance (and I rally mean "you") :rofl:
Waning I know! I even think I've given up the hunt for an upgraded driveshaft! Blasphemy! And stock rear axles?! OMG. I am in the automotive wilderness.

--Peter
 

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At this point a Camry will probably run circles around your unfocused hodgepodge of partial commitment to performance built to a budget.
 

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Are these bushings going to reduce wheel hop for us that drag race?
Prob going to increase wheel burn.
:M5launch:
 
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Hey, look, I found a thread.

I think the polys are great for the subframe. They are merely isolators, they do not facilitate or guide any rotational motion, same with the Diff bushings. Now the control arms and other areas.....there is a very specific reason manufacturers go with rubber over poly in those areas....rubber can move in multiple axis and return to it's original shape....Poly can not. so in areas like the control arm where there is a compound movement made, poly bushings will simply deform and crack. That's why all of us hell bent on replacing the rubber bushings in the arms, go to spherical joints....because the motion is compound....if it was single axis rotation, we would simply put in a bronze bushing, or a conventional bearing.
 
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along the lines of what REKIII posted what is the lifespan of a poly bushing for a DD that sees snow & salt?

not having to set normal position on the suspension arms would be the no.1 reason for me switching to poly
 

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get this discussion going again



I'm strongly considering switching ALL bushings to poweflex when I swap out PSS9 for Konis; specifically:
#1
Part Number: PFF5-501Bx2

#2
Part Number: PFF5-502Bx2

#10
Part Number: PFR5-710-10Bx2

#11
Part Number: PFR5-711Bx2

#12
Part Number: PFR5-712Bx2

#13
Part Number: PFR5-713Bx2

the integral link [33326770749] also needs "Normal-Position" ?

#15 (maybe)
Part Number: PFR5-715Bx2

#16 (maybe)
Part Number: PFR5-716Bx2

my concern is with the maintenance on the bushings, people report squeaking and popping form the bushings. I suspect they apply only the single-serving of lube poweflex provides and when it squeezes out the noises begin.

any input as to how KOPR KOTE compares to M1 Synthetic Grease in terms of year round use (salt, snow, rain, winter, summer)
Kopr Kote
http://www.jetlubecanada.com/pages/kopr-kote.html


M1 Synthetic Grease?
http://www.autozone.com/greases-and-gear-oil/lubricant-grease/mobil-synthetic-grease/934751_0_0/



as for taking the bushings off anyone have a single kit that they know will work to remove the above listed bushings?

I emailed schmiedmann but they haven't replied

Schmiedmann - Back most rear sub-frame differential bush remover/installer special tool set (The work can be done directly on the car without removal of the differential)
Schmiedmann - Ball joint rear wheel carrier extractor/installer special tool (The work can be done directly on the car)

or something similar to SPC
Specialty Products Company | SPC Alignment | The Automotive Alignment Leaders
 

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You will not be happy with powerflex in position #'s 1,2,10,11, or 13.

All those points have multi direction motion requiring either rubber or a spherical bearing. The Powerflex or any polyurethane will not give the motion that is needed causing squeaking and eventually cracking of the bushing.
 

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Discussion Starter #18 (Edited)
Put differently, 3, 4, 20, 22, 25 and 26 are the only Powerflex bushings you should be considering. The others should be monoballs or solid or rubber, as the case may be.

--Peter
 

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You can use the powerflex where you are considering, it will stiffen the car, but it will get bad fast. I'm not even sure thesperical bushings are better than rubbers. I like them better, but they are not for everyone.
 
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