diff --git a/java/com/google/gerrit/server/patch/PatchScriptFactory.java b/java/com/google/gerrit/server/patch/PatchScriptFactory.java
index 6fa14e1..96b23c8 100644
--- a/java/com/google/gerrit/server/patch/PatchScriptFactory.java
+++ b/java/com/google/gerrit/server/patch/PatchScriptFactory.java
@@ -26,21 +26,13 @@
 import com.google.gerrit.entities.Project;
 import com.google.gerrit.exceptions.StorageException;
 import com.google.gerrit.extensions.client.DiffPreferencesInfo;
-import com.google.gerrit.extensions.client.DiffPreferencesInfo.Whitespace;
 import com.google.gerrit.extensions.restapi.AuthException;
-import com.google.gerrit.metrics.Counter1;
-import com.google.gerrit.metrics.Description;
-import com.google.gerrit.metrics.Field;
-import com.google.gerrit.metrics.MetricMaker;
 import com.google.gerrit.server.CurrentUser;
 import com.google.gerrit.server.PatchSetUtil;
-import com.google.gerrit.server.change.FileInfoJsonExperimentImpl;
 import com.google.gerrit.server.edit.ChangeEdit;
 import com.google.gerrit.server.edit.ChangeEditUtil;
-import com.google.gerrit.server.experiments.ExperimentFeatures;
 import com.google.gerrit.server.git.GitRepositoryManager;
 import com.google.gerrit.server.git.LargeObjectException;
-import com.google.gerrit.server.logging.Metadata;
 import com.google.gerrit.server.notedb.ChangeNotes;
 import com.google.gerrit.server.patch.PatchScriptBuilder.IntraLineDiffCalculatorResult;
 import com.google.gerrit.server.patch.filediff.FileDiffOutput;
@@ -51,9 +43,7 @@
 import com.google.gerrit.server.project.NoSuchChangeException;
 import com.google.gerrit.server.project.ProjectCache;
 import com.google.gerrit.server.project.ProjectState;
-import com.google.inject.Inject;
 import com.google.inject.Provider;
-import com.google.inject.Singleton;
 import com.google.inject.assistedinject.Assisted;
 import com.google.inject.assistedinject.AssistedInject;
 import java.io.IOException;
@@ -88,27 +78,6 @@
         CurrentUser currentUser);
   }
 
-  /** These metrics are temporary for launching the new redesigned diff cache. */
-  @Singleton
-  static class Metrics {
-    final Counter1<String> diffs;
-    static final String MATCH = "match";
-    static final String MISMATCH = "mismatch";
-    static final String ERROR = "error";
-
-    @Inject
-    Metrics(MetricMaker metricMaker) {
-      diffs =
-          metricMaker.newCounter(
-              "diff/get_diff/dark_launch",
-              new Description(
-                      "Total number of matching, non-matching, or error in diffs in the old and new diff cache implementations.")
-                  .setRate()
-                  .setUnit("count"),
-              Field.ofString("type", Metadata.Builder::eventType).build());
-    }
-  }
-
   private final GitRepositoryManager repoManager;
   private final PatchSetUtil psUtil;
   private final Provider<PatchScriptBuilder> builderFactory;
@@ -130,8 +99,6 @@
 
   private ChangeNotes notes;
 
-  private final boolean runNewDiffCache;
-
   @AssistedInject
   PatchScriptFactory(
       GitRepositoryManager grm,
@@ -139,7 +106,6 @@
       Provider<PatchScriptBuilder> builderFactory,
       PatchListCache patchListCache,
       ChangeEditUtil editReader,
-      ExperimentFeatures experimentFeatures,
       PermissionBackend permissionBackend,
       ProjectCache projectCache,
       DiffOperations diffOperations,
@@ -165,10 +131,6 @@
     this.psb = patchSetB;
     this.diffPrefs = diffPrefs;
     this.currentUser = currentUser;
-
-    this.runNewDiffCache =
-        experimentFeatures.isFeatureEnabled(FileInfoJsonExperimentImpl.NEW_DIFF_CACHE_FEATURE);
-
     changeId = patchSetB.changeId();
   }
 
@@ -179,7 +141,6 @@
       Provider<PatchScriptBuilder> builderFactory,
       PatchListCache patchListCache,
       ChangeEditUtil editReader,
-      ExperimentFeatures experimentFeatures,
       PermissionBackend permissionBackend,
       ProjectCache projectCache,
       DiffOperations diffOperations,
@@ -205,10 +166,6 @@
     this.psb = patchSetB;
     this.diffPrefs = diffPrefs;
     this.currentUser = currentUser;
-
-    this.runNewDiffCache =
-        experimentFeatures.isFeatureEnabled(FileInfoJsonExperimentImpl.NEW_DIFF_CACHE_FEATURE);
-
     changeId = patchSetB.changeId();
     checkArgument(parentNum > 0, "parentNum must be > 0");
   }
@@ -246,11 +203,7 @@
           }
           bId = edit.get().getEditCommit();
         }
-        return runNewDiffCache
-            ? getPatchScriptWithNewDiffCache(git, aId, bId)
-            : getPatchScriptWithOldDiffCache(git, aId, bId);
-      } catch (PatchListNotAvailableException e) {
-        throw new NoSuchChangeException(changeId, e);
+        return getPatchScript(git, aId, bId);
       } catch (DiffNotAvailableException e) {
         throw new StorageException(e);
       } catch (IOException e) {
@@ -268,15 +221,7 @@
     }
   }
 
-  private PatchScript getPatchScriptWithOldDiffCache(Repository git, ObjectId aId, ObjectId bId)
-      throws IOException, PatchListNotAvailableException {
-    PatchScriptBuilder patchScriptBuilder = newBuilder();
-    PatchList list = listFor(keyFor(aId, bId, diffPrefs.ignoreWhitespace));
-    PatchListEntry content = list.get(fileName);
-    return patchScriptBuilder.toPatchScriptOld(git, list, content);
-  }
-
-  private PatchScript getPatchScriptWithNewDiffCache(Repository git, ObjectId aId, ObjectId bId)
+  private PatchScript getPatchScript(Repository git, ObjectId aId, ObjectId bId)
       throws IOException, DiffNotAvailableException {
     FileDiffOutput fileDiffOutput =
         aId == null
@@ -304,17 +249,6 @@
     return Optional.of(getCommitId(psb));
   }
 
-  private PatchListKey keyFor(ObjectId aId, ObjectId bId, Whitespace whitespace) {
-    if (parentNum == 0) {
-      return PatchListKey.againstCommit(aId, bId, whitespace);
-    }
-    return PatchListKey.againstParentNum(parentNum, bId, whitespace);
-  }
-
-  private PatchList listFor(PatchListKey key) throws PatchListNotAvailableException {
-    return patchListCache.get(key, notes.getProjectName());
-  }
-
   private PatchScriptBuilder newBuilder() {
     final PatchScriptBuilder b = builderFactory.get();
     b.setDiffPrefs(diffPrefs);
diff --git a/javatests/com/google/gerrit/acceptance/api/revision/RevisionDiffIT.java b/javatests/com/google/gerrit/acceptance/api/revision/RevisionDiffIT.java
index eadd259..ba35096 100644
--- a/javatests/com/google/gerrit/acceptance/api/revision/RevisionDiffIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/revision/RevisionDiffIT.java
@@ -2865,13 +2865,11 @@
     DiffInfo diffInfo = gApi.changes().id(cId).current().file(symlink).diff(initialRev);
     assertThat(diffInfo.content).hasSize(1);
     assertThat(diffInfo).content().element(0).linesOfB().containsExactly("new content");
-    // TODO(ghareeb): remove conditional assertion when new diff cache is fully rolled out.
-    assertThat(diffInfo.changeType)
-        .isEqualTo(useNewDiffCache ? ChangeType.REWRITE : ChangeType.ADDED);
+    assertThat(diffInfo.changeType).isEqualTo(ChangeType.REWRITE);
   }
 
   @Test
-  public void renameDeleteByJgit_isIdentifiedAsRewritten6() throws Exception {
+  public void renameDeleteByJgit_isIdentifiedAsRewritten() throws Exception {
     String target = "file.txt";
     String symlink = "link.lnk";
     PushOneCommit push =
@@ -2908,9 +2906,7 @@
             "rename to link.lnk");
     assertThat(diffInfo.content).hasSize(1);
     assertThat(diffInfo).content().element(0).commonLines().containsExactly("content");
-    // TODO(ghareeb): remove conditional assertion when new diff cache is fully rolled out.
-    assertThat(diffInfo.changeType)
-        .isEqualTo(useNewDiffCache ? ChangeType.REWRITE : ChangeType.RENAMED);
+    assertThat(diffInfo.changeType).isEqualTo(ChangeType.REWRITE);
   }
 
   @Test