Aftermarket coolant caps and thermostats are hit-n-miss contingent on both the manufacturer of the vehicle and the replacement part. Can't say whether the 3psi difference between the two radiator caps warrant replacing, however, am more concerned about its ability to hold and release pressure as intended. As stated, the correct part number for the G8 V6 is 92205634.
#NEVER GIVE UP
#AUDACITY OF HOPE
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