Lubricating poly bushes

[Omerta]

Recommended or not, and if so what with? I've done some googling and found arguments each way, and one article that suggested lubricating every fitting except ARBs.

The vehicle is a Cerbera that is being rebuilt as a road legal competition car with PowerFlex poly bushes all round. I don't want to be hearing squeaks on every bump...

Cheers

[Mr2Mike]

They need lubricating or they will squeak all the time. In fact they will probably start squeaking at some stage anyway. Use silicone grease, mineral based greases can degrade the polyurethane.

[Omerta]

Thanks

[Avocet]

My Powerflex bushes arrived with a sachet of something that looked like "copperslip" grease. I'm not sure if that's what it was though.

[taznuv]

I had my GTV rear suspension rebushed with poly bushes and the sqeaking drove me nuts, the place that sold them to me said they'd not had any other complaints...

[chevy-stu]

I have poly bushes all round and the squeaking is rather excessive. Good tip about the Silicone spray from Halfrauds.
I'll try that so I stop sounding like grandmas rusty old bed when i go over a speed hump... !


(interesting comments on a US car forum I frequent say you should not use poly bushes on and reciprocating parts like wishbones, suspension arms etc.. as they 'bind and stop free movement, ok on roll bars)

[Avocet]

This is all very depressing! Mine have behaved faultlessly since they were fitted (although the car does few miles and usually in the dry). Mine were extremely hard compared to rubber ones. There was nowhere near as much "wind-up" in the material and they came with an inner steel sleeve that was supposed to do the pivoting. The sleeve was a fairly loose fit in the inside of the bush. I assumed the intention was that the polyurethane would never be expected to "twist" like the rubber does?

[Mr2Mike]

Avocet said:

I assumed the intention was that the polyurethane would never be expected to "twist" like the rubber does?

You get a bit of both generally, the sleeve (or crush tube) is usually a tight enough fit that for small deflections the polyurethane distorts, and for large deflections the sleeve turns within the bush.

I'm certainly not convinced that poly bushes are the wonderful things the manufactures say they are, or claims about their longevity. The harder the material the better they seem to work, but then you might as well go for nylon (if motion only in single axis) which at least is a decent bearing surface.

[Avocet]

These were pretty loose. The internal sleeve would fall out under its own weight if I turned them on end. That said, they compressed a bit when pushed into their outer housings but it was still easy to rotate the inner sleeve with just figer pressure.

[PhillipM]

Not a particular fan of polybushes - well, off the shelf ones at least - but I've found the best stuff for them is Silkolene's Techwax which is a 'dry' motorcycle chain lube, fantastic stuff.