Sinister Diesel Fuel Injector Sleeve (Injector Cup) – 7.3L Powerstroke
Fits 1994–2003 Ford F-250 & F-350 Super Duty | 2000–2003 Ford Excursion
Key Features
• Precision-machined replacement injector sleeve (also known as injector cup)
• Prevents diesel fuel from leaking into the cooling system due to cracked or split factory sleeves
• Protects against coolant contamination, overheating, and reservoir overflow
• Direct-fit design for easy installation and a leak-free seal
• Built from premium, corrosion-resistant materials for long-term durability
• Ideal preventative replacement whenever injectors are serviced
Why Upgrade to the Sinister Diesel Injector Sleeve
The 7.3L Powerstroke is legendary for reliability, but one known weak point is the factory injector sleeves. When they crack or split, diesel fuel can leak directly into the cooling system — contaminating coolant, creating pressure in the reservoir, and leading to serious engine damage if not caught early.
At Sinister Diesel, we’ve tested multiple injector sleeve designs from leading manufacturers to identify which ones hold up best under heat, pressure, and vibration. The result is our premium-grade sleeve — machined from high-strength, corrosion-resistant material and precision-fit to seal perfectly every time. These are the same sleeves trusted in our in-house builds and proven through extensive real-world testing.
Whether you’re replacing injectors or performing preventative maintenance, this sleeve is the reliable fix that helps ensure your 7.3L Powerstroke runs clean and cool for years to come.
Product Description
The Sinister Diesel Fuel Injector Sleeve (Injector Cup) restores the critical seal between your injector and cylinder head, preventing diesel fuel from entering the coolant system. Each sleeve is precision-machined for an exact fit, providing superior sealing performance and long-term reliability under the harsh operating conditions of the 7.3L Powerstroke.
Installing these sleeves during any injector service is one of the best ways to prevent cross-contamination between your fuel and cooling systems. Protect your investment and maintain dependable performance with this precision-engineered upgrade from Sinister Diesel.
Kit Includes
• (1) Sinister Diesel Fuel Injector Sleeve (Injector Cup) – for one injector (eight required per engine)
Why Buy From Sinister Diesel
Since 2009, Sinister Diesel has been the trusted source for Powerstroke performance and reliability. Every part we offer is tested in-house and proven in real-world conditions to meet our exacting standards for quality, fitment, and durability. Backed by fast shipping, knowledgeable U.S.-based support, and thousands of satisfied customers, Sinister Diesel is the name you can depend on to keep your 7.3L Powerstroke performing its best.
