Rubbery steering wheel feel over bumps

[cornershop]

I’m in the process of getting the bushes fitted by my local and recommended specialist (SSG automotive, ottershaw).

Powerflex black in the front lower lateral arm rear Bush.
Powerflex purple in the upper wishbones
Lemforder lower shock bushes.
The banana arms had been replaced earlier this year with Lemforder items

I’ve just commissioned SSG to do similar on the rear, so will be a couple of weeks before I can test drive:
New Lemforder lower wishbones, with PF black in the front receptor
New Lemforder upper wishbones, with PF purples to be fitted.
New Lemforder lower shock bushes

Q to those that have fitted poly bushes - is future re-lubrication a requirement, or are they fit and forget? I.e. do they get squeaky after a while?

[J44EAG]

The above spec is the best compromise. In that respect, its as good as you can get for a road car. The PF Blacks in those locations will help directional stability with the added bonus that the steering will be much more "pointy" than you will have experienced to date.

As regards fitting the PF bushes, use loads of copper grease within the bush when fitting. That usually comes as part of the kit.

It is essential that the central compression tube fitted into the bush, over hangs the bush by around half a mm. Slight machining of the drop arm bush material may be required to ensure the bush material does NOT bind on the body shell mounting points. Once fitted, the mechanic must ensure that the drop arms have full and free movement between the fully up position of the arm to the fully down position. The arms should fall under their own weight.

Note a PF bush functions completely differently to the Metalastic type which will be removed. In the Metalastic OE types, the outer tubular shell, the rubber bush material and the central compression tube are all bonded together. As the arms rise and fall when the suspension is in use, a torsional wind up load is exerted on the rubber bush material. Bolts are tightened with the weight of the car on the floor. In service, tremendous stress is exerted on the rubber bush. No wonder it gives up by about 60k miles! With the PF bush, the compression tube revolves as the suspension rises and falls. There is no torsional windup effect so the poly-urethane bush is un-stressed in service. Grease helps to stop squeaks and provides lubrication. Any squeak should be investigated....ie for lack of sufficient grease or binding of the bush within the body shell mounting point. Essentially though, PF bushes are fit carefully and then effectively forget.

Provided your garage grease well and ensure the bush is not tight in the body shell mounting, you should have a problem free fit.

Mike

[cornershop]

Thanks Mike

I am hopefully collecting my car today after all of the bush replacement work

Will report my findings after a lengthy test drive

[jeremy156]

Shirish, you never came back with your results - did you find the improvement you were hoping for?

Jeremy

[cornershop]

Shirish, you never came back with your results - did you find the improvement you were hoping for?

Jeremy

Hello - no it didn’t fix the rubbery feel, but sharpened responses nicely without introducing NVH.

Rubbery feel was sorted with new height sensors all round - I figure the car was running higher than it should have been due to faulty sensors.

[J44EAG]

Sensors are usually problem free in service. I`ve not heard of a failure ever....They either work or they don`t. It should be noted that the offside front sensor becomes redundant after about the first year of manufacture, ie about MY04 onwards. It is then there really just to act as electronic "completeness". Only the near side sensor acts to provide levelling on the front. Not a lot of people know that. Sensors should be checked for mechanical soundness after about 100K miles of use. The knuckle joints can begin to fall to bits. However, they do seem to keep going even when about to mechanically disintegrate.

Running high or low can be electronically adjusted using a dealer level diagnostic unit. When I first bought my own car, running heights were all over the place. Whilst having an initial sort out at Tom Lenthals establishment, we also tackled the wonky look to the car. Firstly we levelled the car on a flat surface to standard ride height, then I had 10mm taken off the ride height electronically. That surprisingly had quite a marked effect just on its own.

Mike