What Is the Liquid in Liquid Filled Auto Gauges?

Liquid-filled gauges have many benefits.

Standard auto gauges have no liquid filling and are sufficient for daily use. Gauges in high-performance or heavy use vehicles are often filled with certain liquids to reduce shock and enhance accuracy.

Glycerin

Glycerin is the most commonly used gauge liquid as it is readily available in any pharmacy and provides reliable, basic performance. It is ideal for normal temperature ranges and standard equipment use and is low-cost being found in nature and the laboratory.

Silicone

Silicone liquid is less common and is used mainly in high temperature situations or when gauges are expected to withstand heat and cold thanks to its semi-metallic nature. Silicone liquids are man-made and formed when oxygen and silicon are combined with the aid of very high temperatures.

Insulating and Silicone Oils

Silicone blend oils and other insulating oils are even less common than silicone liquid and are found mainly in top-end racing rigs. These gauges are preferred by professional racers due to their blend of properties. They are able to withstand the most extreme of conditions like their silicone liquid cousins, but also have greater fluidity and freedom of movement for the gauge needles thanks to a lighter and more fluid oil/silicone blend.

References

• LENZ Fluid Power Specialist: Advantages of Liquid Filled Gauges
• Lab Commerce Inc: Liquid Filled Gauges
• No Shok Inc: Liquid Filled Pressure Gauges