Why not use bushing grease on a-arm bushings? Options

[Tdskip]

Hi guys - I know how it is commonly done including Ian’s great video. Is there a reason why not to use bushing grease instead of softsoap?

So you want the bushing NOT to move or rotate ones installed? I assume that is a reason but wanted to ask.

Thanks.

[Superhawk996]

There is a obviously a heated debate of poly vs. rubber. Each has it's place depending on whether you intend to use the car primarily on the street or whether you want to trade comfort and maintenace for decreased compliance.

But ask yourself this. Why is it that all major OEM's use rubber busings?

It is not simply money. Check under any new Porsche, Ferrari, Lamborghini, Audi, BMW, etc., you will find rubber bushings. Each OEM referenced could use polyurethane if it were simply the "smarter" choice. The fact is that rubber is simply superior when it comes to balancing all the conflicting trade-offs (ride, steering, NVH, durability, freedom from maintenance to name a few).

There is far more to a modern rubber bushing than meets the eye.

A rubber bushing can be designed to have a wide variety of characteristics via rubber durometer, section thickness, voids, bonding methods, physical construction methods affect it like axial pre-load by squeezing it into a "can", etc. Want dual durometer rubber in the same part? Dual durometer can, and, has been done. Rubber bushings can be tuned to a combination of static rates (simple deflection in any single axis), Dynamic rates (how does the rate respond to varying road frequency inputs). They can be designed to have incredibly high damping characteristics at a single freqency via tuned chambers that contain glycol (called hydro bushings).

Yes, I acknowledge that the 1970's era 914 bushing is indeed very simple, but, they were engineered for a purpose which was to optimize the balance between ride, handling, maintenace, and outright durability. You may shift any of the conflicting characteristics (like ride vs. handling) to gain an advantage, but, you will not find a better material than rubber to provide an optimal solution for general street use.