Permatex Ultra Red 81630 is a high-temperature RTV silicone gasket maker designed to create custom gaskets or rejuvenate existing ones on automotive engines and exhaust systems. This advanced formula delivers reliable sealing performance where high heat and thermal cycling demand durability, making it ideal for header, manifold, turbocharger and slip-fit exhaust applications.
Unlike standard RTV red sealants, Ultra Red resists extreme temperatures and oil exposure while remaining sensor-safe and non-corrosive. Its low-odor formulation meets original equipment manufacturer (OEM) specifications and performs at the level of pre-cut OE silicone gaskets, giving technicians and DIY mechanics confidence when working on temperature-critical engine seals.
Features and Benefits
- High Temperature Resistance: Withstands up to 650°F (343°C) intermittent exposure, outperforming standard RTV red for demanding engine compartment repairs.
- Dual Purpose Formula: Functions as both a gasket maker to create new seals and a gasket dressing to condition original gaskets during reassembly.
- Sensor Safe and Non-Corrosive: Low-odor, non-corrosive design protects oxygen sensors and electronic engine components from damage during application and curing.
- Resists Oil: Resistant to engine oils and common shop fluids for long-lasting performance in wet engine environments.
- OEM Specified Performance: Meets performance specifications of original equipment silicone gaskets, ensuring reliability in factory-critical sealing areas.
Specifications
- Brand: Permatex
- Model: 81630
- Size: 3.35 oz
- Type: High-temperature RTV silicone gasket maker
- Maximum Temperature: 650°F (343°C) intermittent
- Sensor Safe: Yes
- Non-Corrosive: Yes
- Low Odor: Yes








