VEVOR Coolant Pressure Tester Kit, 47Pcs Radiator Vacuum Refill Kit with 3 Metal Adapters, Universal Fit, Automotive Cooling System Pressure Tester Tool, with Pressures Pump & Aluminum-Plastic Filler

The kit includes vacuum refill tools, which are highly recommended for the 6.4L engine to prevent air pockets from forming in the cylinder heads during a coolant change. Using the manual pump, you should pressurize the system to the PSI rating stamped on your original radiator cap (usually 18-21 PSI) to check for leaks. Because this is the comprehensive 47-piece version, it contains the specialized adapters required for the wide cooling systems found on heavy-duty Dodge and Ram trucks.

This 47-piece kit is a universal set, but for your Ram 2500 with the 6.4L HEMI, you will specifically use the threaded aluminum or plastic adapters that match the radiator neck or coolant expansion tank. Most 6.4L Ram models utilize a standard threaded pressure cap; look for the adapter in the kit that matches the diameter and thread pitch of your factory cap.