Due to having a higher density, Viton has the widest temperature range of -40°F to over 400°F (-40°C to over 240°C) making it a perfect choice for higher temperature applications. Viton® also has the largest range of chemical resistance, i.e., it is resistant to silicone oil and grease, mineral/vegetable oil and grease, aliphatic, aromatic, and chlorinated hydrocarbons, non-flammable hydraulic fuels as well methanol fuels, and more.
When selecting spark plugs for vehicles, it is essential to consider factors such as compatibility, heat range, electrode design, and material composition. High-quality spark plugs, including iridium spark plugs, are designed to withstand the demanding conditions of automotive operation, providing reliable ignition and combustion. Choosing reputable suppliers and manufacturers known for producing high-quality spark plugs is crucial to ensure the reliability and longevity of these critical components in the vehicle's ignition system.
Regular maintenance and inspection of the valve cover gasket are essential to avoid such issues. If a leak is detected, replacing the 4.0 valve cover gasket should be done promptly to prevent further complications. It is a relatively inexpensive fix compared to the cost of ignoring the problem and allowing it to escalate into more extensive engine damage. - Apply a small amount of gasket sealant or grease on the threads to facilitate installation and prevent leaks.mm

What are Oil Seals?
DIN
Silicone compounds or “VMQ” offers a wide range of traditional operating temperatures starting at -60°C to 200°C (-140°F to 392°F).
Applications However, proper installation and maintenance of TC oil seals are crucial for their effective functioning