Why do we need suspension fluid?
Suspension fluids are just as vital to the smooth running of your vehicle as its mechanical components. Aside from hampering the inconvenience of vibration and jolts when driving, they also perform a number of duties which as a whole contribute to safe handling, longer life of parts, preventing rust, corrosion and failure of components of your suspension system.
Working requirements of suspension fluid
Suspension fluids need to provide this consistent damping over all terrains and road surfaces, across a wide temperature range. This is required over the service lifetime of the fluid, meaning that properties such as shear stability and oxidation resistance are important. The fluid also controls wear and friction between moving parts and seals, has a very low foam performance and rapid air release, as well as being compatible with all components in the system.
Suspension fluid viscosity
To provide consistent damping over a wide temperature range, the suspension fluid must have a high Viscosity Index (VI). The viscosity of high VI oils changes less with temperature, and thus their flow within the unit is more consistent. This delivers a consistent feel for the rider from the initial start to maximum temperature. High VI fluid is made by using naturally high VI base oils, but more importantly, by using a viscosity modifier or viscosity index improver. These are long-chain polymers that can shear (break down) in use unless you chose highly shear stable versions. These will maintain their VI and perform for the desired service interval.
Other important properties which are enhanced by base oil choice and performance additives include:
- Foaming tendency and stability
- Air release
- Oxidation resistance
- Wear protection
- Friction
- Seal compatibility
Suspension fluid weights
One of the biggest mistakes people make when choosing suspension fluid is to compare weights by manufacturer. However, oil weights are not standardised and each manufacturer labels their lubricants differently. As a result, comparing grades described similarly may result in two completely different viscosity fluids.
A better way of selecting suspension fluids is to use recognised systems such as SAE and ISO. These combined can help provide more accurate insight, although it is still difficult to compare fluids if their VI is different.
> FUCHS Silkolene suspension fluids use both SAE and ISO in their description to help with fluid selection. SAE defines the viscosity at high temperatures (100⁰C) and ISO does the same at 40⁰C.
Which suspension fluid do I need for my vehicle?
We understand that choosing the correct lubrication for your vehicle can be a complex task.
The > FUCHS Oil Chooser eliminates the guesswork allowing you to find the right product in under 1 minute. Simply enter your vehicle registration plate or make and model to discover lubricants relevant to your specific vehicle.
Alternatively, contact our team using the enquiry form below.
ANY QUESTIONS?
Here at FUCHS UK, our teams of experts are always on-hand to answer any of your questions. With years of experience in automotive lubrication you can trust that you’re in safe and knowledgeable hands.
NEED TECHNICAL HELP?
Speak to our technical team today to learn more about how FUCHS products can help you.