Aluminum DIESEL Cap and DEF Cap for 2019-2021 Dodge Ram 6.7L - Tight

Our review of the Aluminum DIESEL Cap and DEF Cap focuses on fit and protection for the 2019-2021 Dodge Ram 6.7L models. This cap is for owners who need a direct replacement that matches the latest Ram fuel filler style with three vertical plastic posts; the single biggest reason to consider it is the combination of an airtight seal and a durable anodized billet aluminum construction that keeps contaminants out of the diesel system.

Key Features

• Vehicle Specific Fit: Designed only for 2019-2021 Dodge Ram 1500, 2500 and 3500 diesel trucks with three vertical posts at the filler, so buyers get a precise fit when the vehicle matches those years and filler posts.
• Airtight Protection: The cap seals tightly to keep out dust, water, rain and snow, helping to protect the fuel system from contamination and costly repairs.
• Durable Construction: Machined from anodized billet aluminum for long-term resistance to weathering and the daily wear of filling the tank.
• Magnetic Convenience: A permanent neodymium magnet holds the cap to the truck while filling, reducing the chance of dropping the cap on the ground.
• Complete Kit: The product ships with the housing and the part number XJ-1258 reference, providing the components needed for immediate swap-in on compatible trucks.

Who It's For

This cap is best for owners of 2019 through 2021 Dodge Ram 6.7L diesel pickups (1500, 2500, 3500) who have the three vertical plastic posts at the fuel filler and want an aluminum, permanently magnetic replacement that looks and feels more durable than stock plastic. It suits technicians, fleet owners, and DIYers who prioritize a tight seal and corrosion-resistant material.

It is not for owners of Dodge Ram models made before 2019 or trucks without the three vertical posts at the filler; those buyers should look for a cap explicitly listed for their year and filler style. Also, if a softer, nonmagnetic cap is preferred for easier handling, this magnet-equipped cap may not be ideal.

Pros & Cons

Pros

• Precision fit for the stated 2019-2021 Ram models, giving confidence in compatibility.
• Strong protection against dust and water thanks to the airtight design.
• Durable anodized billet aluminum construction that resists long-term exposure.
• Magnet holds the cap to the truck while filling, improving convenience.

Cons

• Magnet strength and ease of removal receive mixed feedback; some users find it holds too tightly or is harder to put back on.
• Not compatible with Dodge Ram models prior to 2019 or fillers without three vertical posts.

Specifications

Product Name	Aluminum DIESEL Cap and DEF Cap
Fitment	2019-2021 Dodge Ram 6.7L 1500/2500/3500
Fuel Filler Style	Three vertical plastic posts at filler
Material	Anodized billet aluminum
Feature	Permanent neodymium magnet
Included Components	Comes with housing
Part Number	XJ-1258

Our Verdict

The Aluminum DIESEL Cap and DEF Cap is a practical, value-minded replacement for 2019-2021 Dodge Ram 6.7L owners who need a secure, long-lasting cap that resists the elements and looks better than stock plastic. It is good value for those who match the exact filler style, though buyers should be aware the magnet can be strong and may affect ease of handling.

Frequently Asked Questions

Will this cap fit my Ram?
It fits only 2019-2021 Dodge Ram 6.7L trucks with three vertical plastic posts at the fuel filler; it is not compatible with models before 2019.

Does the magnet hold the cap while filling?
Yes, a permanent neodymium magnet is included to hold the cap to the truck while filling, though some users report it can feel very secure and take extra effort to remove.

What does the kit include?
The package includes the aluminum cap and housing as supplied under part number XJ-1258 for immediate replacement installation.