Lift Pump functionality is a CRITICAL part of the fuel system on any diesel vehicle. The 6.5L is no exception.

There are different requirements depending on the year of the truck and what type of injection pump it uses.

• 5 PSI is the BARE MINIMUM

  • Factory Stanadyne spec, however, we always recommend more since factory specs cause high failure rates

• 10-14 PSI is the Quadstar Recommendation

  • We like to see >10 psi under all load demands, which stock lift pumps can't do

    • Any less and we see a reduction in performance

    • Any more is un-necessary, at any power level a DS4 pump is capable of

• 5 PSI Minimum

• < 10 PSI Maximum

  • The DB2 pump, in stock form, does not want to see more than single digit inlet pressure from the lift pump. Higher pressure will cause timing to advance undesirably

• We recommend upgrading any mechanical lift pump truck to an electric lift pump that can supply steady pressure and take all stress off the mechanical transfer pump that's inside the DB2 injection pump.