Suspension Mounts - Rubber Vs Polyurethane

[mattross]

My rubber suspension mounts have failed, and the suspension place said it not uncommon in Mk3 golfs why not try polyurethane ones.

Anyone running polyurethane ones? what do you think of them?

[Water Boy]

Polyurethane is stiffer so it will give a harsher ride.

But in saying that the car will fell "tighter"

[h100vw]

Exactly which bushes are they saying are worn?

Having been in the VW modifying game since 1992, I am now more than ever, not convinced about polyurethane being the best medium for bushes on road cars.

Gavin

[mattross]

Upper and Lower Rubber mounts are worn... and compressed...

Why do you say that about the poly ones? Too harsh?

[h100vw]

That still doesn't really say what's gone.

Are they talking about the top mounts, which have the bearings in them?

Or maybe the wishbone bushes, of which the rear one would likely be shot away for sure.

The rear struts have rubber bushes at the top of the shock and inside the car. They get a bit soft looking but I don't reckon you'd notice the difference by fitting new ones.

Poly anywhere in the suspension, is likely to transmit road noise into the cabin to a degree.

I wouldn't but then I have done all this stuff in times gone by.

[kaanage]

Is that because of the NVH just affecting comfort or leading to parts breaking?
When I fitted poly bushes in my old Fiat, it was magical to drive, especially on the track, but I kept breaking suspension arms and mounts.

[mattross]

The top Front and rear Shock/Strut Mounts, with the bearings
REARS: The rubber is definately getting hard and i can see the line where they used to sit.
FRONTS: same deal, can see a few mil play in them... less than 3 years old too...

http://www.facebook.com/photo.php?pi...2&id=519165064
http://www.facebook.com/photo.php?pi...2&id=519165064

I had new rubber ones put in 3 years ago... and now the rear tyres are scrubbing out on the arches (never used too).... handling is also not as good as once before, and i get a little bit of what feels like rear wheel hunting/tracking in a rut???

The VW dealer said he has changes thousands of these and reckoned there is a desgin fault with them and rabbled about a class action against VW years ago because of them.... he suggested polys, so i asked the forum

I was thinking of upgrading to some coilovers with the polys...(or maybe pillow mounts)
The other alternative is to get heavy duty rubber ones (VR6)

All comments welcome

[rayray086]

I'd suggest going against polys for bushes where movement is required, e.g. the rear control arm bushes. There was an extensive thread on the Vortex in the Mk3 section about poly vs rubber and even in race applications, poly bushes/mounts are not the be-all, end-all solution. Bushes like the rear control arm one requires lateral movement in which the rubber provides to a certain degree, but still restrictive when it comes to suspension movement. However they're perfect for standard applications as service noise are kept to a minimum and comfort at a maximum (until the rubber disintegrates from the constant flexing). Polys on the other hand are harder and even more restrictive, not allowing the lateral movement the control arm requires when negotiating a corner. The best option here (in terms of race applications) would be a spherical ball bearing which provides the movement the control arm requires in a situation where weight transfer occurs.

Having said or that, I'm currently using heavy duty front rubber strut mounts, R32 solid rubber control arm (rear) bushing, poly steering rack mount, poly rear and front (BFI's stealth range) engine mounts, G60 solid rubber transmission mount and everything else stock OEM. I've changed out pretty much all the bushings/bearings/mounts except for the rear beam bushing, and have had rear poly strut mounts at one stage but changed them for stock ones again cos of the squeaking. I've got standard front strut mounts at home waiting for some a mod before they go in, but once they're done I'll be replacing the HD front rubber strut mounts. They've maintained their shape throughout the years (been about two years since I've bought them) and work very well, but they're bulky and I just want to replace them with mounts that help the car sit lower (don't mind me, I think a little different haha). My reason for choosing the stiffer R32 control arm rear mount was for more stability when driving straight, which I've noticed. At highway speeds it feels nice and firm.

My opinion is if you're gonna be keeping the car on the road and using it as a daily, just go for OEM rubber. Yes they're not a great design and they don't last as long as you want them to be, but at least you've got comfort. They're not crazy expensive and changing them every three years would just give you the incentive to check under the car more often. If you use the car for spirited drives too, some uprated rubbers are good like the heavy duty mounts and the solid rubber bushings. As for polys, I'd stay away unless the desired effect can only be achieved by polys (whatever that may be).

Edit: And the Vortex thread - VWVortex.com - Poly vs. Rubber Bushings

Edit 2: And another - VWVortex.com - Why (Rear) Poly Bushings Are Bad