Product Description
Hamilton’s 1.45" tappets are a proven upgrade for Cummins valvetrains. The wider 1.45" footprint increases lobe contact area versus early 1.1" lifters to promote better lobe life with today’s low-zinc oils, and they clear the 12V fuel pump eccentric. Ideal for stock and performance cam profiles.
Fitment
- 1989–2016 Dodge/Ram Cummins 5.9L & 6.7L, 12V & 24V
- Direct replacement set; designed to work with Hamilton cast/steel cams
Note: Hamilton lists these as working with all 1989–2016 Cummins applications. Verify engine/trans year before ordering.
Cross-Reference / Alternatives
- Upgrade to DLC-coated billet tappets (performance/high spring pressure): Hamilton 07-T-002
- Pair with Hamilton cams: 07-C-178/208 Cast • 07-C-188/220 Cast • 07-C-188/220S Steel • 07-C-220/240 Steel
- Related valvetrain: Hamilton 07-S-003 103# Valve Springs • Hamilton 07-P-004 Pushrods • Hamilton 07-C-002 Bolt-On Cam Retainer • Hamilton 07-C-001 Zinc Additive
- OEM-style tappets (individual): Cummins 3931623 (1989–1998 12V) • Cummins 3942565 (1998.5–2002 24V)
FAQ
Why 1.45" tappets instead of 1.1"?The larger 1.45" face provides more cam lobe contact area, improving durability—especially with modern low-zinc oils—and avoids fuel pump eccentric interference on 12V engines.
Are these compatible with Hamilton performance cams?
Yes. They are designed to work with Hamilton cast and steel profiles like 178/208 and 188/220. For very high spring pressures/RPM, consider the DLC-coated 07-T-002.
Do I need to replace tappets when I change the cam?
Yes—always install fresh tappets with a new cam for proper break-in and longevity. Use Hamilton Zinc Additive during break-in.
Will these work on both 12V and 24V engines?
Yes. They’re listed for 1989–2016 Cummins 5.9L/6.7L 12V & 24V applications. Verify your exact year/engine before purchase.
