Questions and answers

We have a special instrument to measure hardness of polyurethane and rubber. Mainly, Shor method scale A is used to measure hardness; our parts are examined by quality control for this parameter. Most rubber parts have 65-unit hardness. When comparing parts made from different materials you may feel that polyurethane parts are softer. The thing is that polyurethane parts under compression (in the area of small deformations) have an elasticity module two times higher than rubber parts. For example, you can imagine as if you are compressing one spring (rubber) or a ball of springs (polyurethane). Polyurethane molecules work both for compression and for twisting (torsion) more efficiently and return to the original state faster than rubber molecules. That is why your feelings are subjective.

Bushings serve as hinges and flexible joints between suspension parts at the points where a vehicle chassis has to change its geometry to level the body in relation to road irregularities. They are specially designed for each car type to reduce noise and vibration, and they serve as a barrier between the road (vibration) and yourself.

Rubber is very good as vibration and noise absorber, cars without them would be much harder and noisier. Besides, rubber is less expensive and is widely available. In mass production of parts, rubber is most practically feasible and meets the warranty period specified by the maker.

The main factors are the cost, regular supply and marketing. Raw material for POLYURETHANE is approximately 10 times higher in price, and the production period is 90 times longer as compared with rubber.

Automobile makers purchase many components. If a major car maker decides to use polyurethane bushings in the whole range of cars produced, then it has to find a supplier capable to make polyurethane parts in million pieces a year. At present, we do not know such a company that could be capable to make polyurethane parts in time in hundred thousands and in a wide assortment for delivery to a car assembling conveyor. A 10 percent rise in cost of one part multiplied by millions decreases car competitiveness. Standard rubber parts meet warranty periods without serious damages during two or three years. Would you make your choice in favor of any specific car model based exclusively on the fact that polyurethane parts have been used in the suspension? Probably not.

The general answer is no. You can get the necessary information of special hinges on АККС web site. For off-road races such as Paris-Dakar and others, polyurethane bushings are widely used in suspensions.

Practically all rubber parts have been replaced on such vehicles with polyurethane, silicone, fluorelastomer and other expensive polymers.

IMHO: There are many automobile categories jointly termed as “sports, racing, records, buggy, prototypes, etc.” including the so called “formula” cars. Racing cars run on special tracks, and their suspension is furnished with all-metal hinges without free play for maximum hard (more correctly, accurate) steering control and suspension; such hinges do not provide comfort and absorption of noise and vibration, which is not essential for specially prepared tracks.

The service period of such hinges and bushings is counted in hours. But such construction is optimal for sports providing precise control of bolides at high speeds. It is not suitable for everyday trips.

However, rubber bushings are used on most serial “sports” cars presently made. Usually, their usage is conditioned by mass production. In most cases, owners of such cars tune them up for many parameters including suspension.

We deliberately abridge our answer because we are not experts in designing and constructing formula bolides, and suspension constructions may differ significantly depending on competition conditions and car categories.

If your car has any rubber bushings, which can be replaced with polyurethane parts according to our catalog, you will only improve suspension characteristics and performance.

Handling control and maintaining suspension geometry under extreme driving conditions is the result which you probably missed. The tires maintain a maximal while sharp acceleration, braking and in turns. You feel the car and its capabilities better. If we consider our roads extreme, then POLYURETHANE is what you need!

Our polyurethane parts improve behavior of a car on the road decreasing unwanted deformations in suspension and eliminating a “squeezing” effect inherent to rubber parts. It means that a suspension always performs in the mode provided for by designers. Correctly selected and installed polyurethane parts ALWAYS perform better, absorbing shocks, vibration and reducing noise in comparison with rubber. An important moment is a problem of quick wear of genuine rubber parts. Engineers and designers often take into account only road operation mode when designing …

In our practical work we came across not once with a situation when even new genuine parts required replacement after 15,000-20,000 km because of imperfect construction or operation of a car on unsuitable roads. Practically on all models made in Japan we can find such units where regular replacement of rubber parts is required. For the owners, this means loss of money and time.

Just the same cause was considered above, but with a different accent. If tires have better contact with the road, then you can control the car more accurately and tire wear is much less. After installation of POLYURETHANE parts, tire wear will reduce TWO times!

We do not assert that this is possible right for you as many factors exist that affect directly tire wear (wheel balancing and proper tire pressure, driving manner, toe-in and camber adjustment and other).

When visiting a tire-fitting shop you can see a lot of discarded tires with uneven tread wear. Especially, wear on inside or outside surface with an excellent tread condition in the center. In this case, low tire pressure was not a principal reason of wear; the answer is evident: in most occasions this happens due to worn-out rubber bushings.

To compensate loss of rubber parts properties, car makers recommend regular checks and adjustments of toe-in and camber in accordance with the operation instruction (in average, once every 10-20.000 thousand km).

We design all our products so that they can be installed by any qualified mechanic. Sometimes, it is more difficult to remove old rubber parts than to install new parts (when assembling/disassembling by oneself), these are the main problems. In each specific case we provide detailed comments on installation, if necessary.

At the designing stage, changes are made to a construction of genuine parts in order to maximally use ALL physical and mechanical properties of POLYURETHANE. Production technology allows for manufacturing parts from POLYURETHANE with slight external distinctions from OEM parts but preserving all geometrical coupling sizes of the original. We do not copy external forms of rubber parts as operating surfaces of rubber parts often have forms dictated by technological specifics of rubber casting.