diff --git a/test/units/testsuite-55.sh b/test/units/testsuite-55.sh
index 379ea9e5697..f0837d22a3e 100755
--- a/test/units/testsuite-55.sh
+++ b/test/units/testsuite-55.sh
@@ -22,7 +22,13 @@ fi
 
 rm -rf /etc/systemd/system/testsuite-55-testbloat.service.d
 
-echo "DefaultMemoryPressureDurationSec=2s" >>/etc/systemd/oomd.conf
+# Configure oomd explicitly to avoid conflicts with distro dropins
+mkdir -p /etc/systemd/oomd.conf.d/
+echo -e "[OOM]\nDefaultMemoryPressureDurationSec=2s" >/etc/systemd/oomd.conf.d/99-oomd-test.conf
+mkdir -p /etc/systemd/system/-.slice.d/
+echo -e "[Slice]\nManagedOOMSwap=auto" >/etc/systemd/system/-.slice.d/99-oomd-test.conf
+mkdir -p /etc/systemd/system/user@.service.d/
+echo -e "[Service]\nManagedOOMMemoryPressure=auto\nManagedOOMMemoryPressureLimit=0%" >/etc/systemd/system/user@.service.d/99-oomd-test.conf
 
 mkdir -p /etc/systemd/system/systemd-oomd.service.d/
 echo -e "[Service]\nEnvironment=SYSTEMD_LOG_LEVEL=debug" >/etc/systemd/system/systemd-oomd.service.d/debug.conf