diff --git a/core/src/main/java/org/elasticsearch/cluster/metadata/MetaDataIndexUpgradeService.java b/core/src/main/java/org/elasticsearch/cluster/metadata/MetaDataIndexUpgradeService.java
index 44b65c7f8c9..9b9a56dee32 100644
--- a/core/src/main/java/org/elasticsearch/cluster/metadata/MetaDataIndexUpgradeService.java
+++ b/core/src/main/java/org/elasticsearch/cluster/metadata/MetaDataIndexUpgradeService.java
@@ -113,49 +113,10 @@ public class MetaDataIndexUpgradeService extends AbstractComponent {
         IndexMetaData newMetaData = upgradeLegacyRoutingSettings(indexMetaData);
         newMetaData = addDefaultUnitsIfNeeded(newMetaData);
         checkMappingsCompatibility(newMetaData);
-        newMetaData = upgradeSettings(newMetaData);
         newMetaData = markAsUpgraded(newMetaData);
         return newMetaData;
     }
 
-    IndexMetaData upgradeSettings(IndexMetaData indexMetaData) {
-        final String storeType = indexMetaData.getSettings().get(IndexStoreModule.STORE_TYPE);
-        if (storeType != null) {
-            final String upgradeStoreType;
-            switch (storeType.toLowerCase(Locale.ROOT)) {
-                case "nio_fs":
-                case "niofs":
-                    upgradeStoreType = "niofs";
-                    break;
-                case "mmap_fs":
-                case "mmapfs":
-                    upgradeStoreType = "mmapfs";
-                    break;
-                case "simple_fs":
-                case "simplefs":
-                    upgradeStoreType = "simplefs";
-                    break;
-                case "default":
-                    upgradeStoreType = "default";
-                    break;
-                case "fs":
-                    upgradeStoreType = "fs";
-                    break;
-                default:
-                    upgradeStoreType = storeType;
-            }
-            if (storeType.equals(upgradeStoreType) == false) {
-                Settings indexSettings = Settings.builder().put(indexMetaData.settings())
-                        .put(IndexStoreModule.STORE_TYPE, upgradeStoreType)
-                        .build();
-                return IndexMetaData.builder(indexMetaData)
-                        .version(indexMetaData.version())
-                        .settings(indexSettings)
-                        .build();
-            }
-        }
-        return indexMetaData;
-    }
 
     /**
      * Checks if the index was already opened by this version of Elasticsearch and doesn't require any additional checks.
diff --git a/core/src/test/java/org/elasticsearch/index/store/IndexStoreBWCTests.java b/core/src/test/java/org/elasticsearch/index/store/IndexStoreBWCTests.java
deleted file mode 100644
index e53358c6631..00000000000
--- a/core/src/test/java/org/elasticsearch/index/store/IndexStoreBWCTests.java
+++ /dev/null
@@ -1,83 +0,0 @@
-/*
- * Licensed to Elasticsearch under one or more contributor
- * license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright
- * ownership. Elasticsearch licenses this file to you under
- * the Apache License, Version 2.0 (the "License"); you may
- * not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *    http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing,
- * software distributed under the License is distributed on an
- * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
- * KIND, either express or implied.  See the License for the
- * specific language governing permissions and limitations
- * under the License.
- */
-package org.elasticsearch.index.store;
-
-import com.carrotsearch.randomizedtesting.generators.RandomPicks;
-import org.apache.lucene.store.*;
-import org.apache.lucene.util.Constants;
-import org.elasticsearch.Version;
-import org.elasticsearch.action.admin.indices.settings.get.GetSettingsResponse;
-import org.elasticsearch.cluster.metadata.IndexMetaData;
-import org.elasticsearch.common.settings.Settings;
-import org.elasticsearch.index.shard.ShardId;
-import org.elasticsearch.index.shard.ShardPath;
-import org.elasticsearch.test.ESSingleNodeTestCase;
-import org.elasticsearch.test.ESTestCase;
-
-import java.io.IOException;
-import java.nio.file.Path;
-import java.util.Arrays;
-import java.util.Locale;
-
-/**
- */
-public class IndexStoreBWCTests extends ESSingleNodeTestCase {
-
-
-    public void testOldCoreTypesFail() {
-        try {
-            createIndex("test", Settings.builder().put(IndexStoreModule.STORE_TYPE, "nio_fs").build());
-            fail();
-        } catch (Exception ex) {
-        }
-        try {
-            createIndex("test", Settings.builder().put(IndexStoreModule.STORE_TYPE, "mmap_fs").build());
-            fail();
-        } catch (Exception ex) {
-        }
-        try {
-            createIndex("test", Settings.builder().put(IndexStoreModule.STORE_TYPE, "simple_fs").build());
-            fail();
-        } catch (Exception ex) {
-        }
-    }
-
-    public void testUpgradeCoreTypes() throws IOException {
-        String type = RandomPicks.randomFrom(random(), Arrays.asList("nio", "mmap", "simple"));
-        createIndex("test", Settings.builder()
-                .put(IndexStoreModule.STORE_TYPE, type+"fs")
-                .put(IndexMetaData.SETTING_VERSION_CREATED, Version.V_1_7_0)
-                .build());
-
-        client().admin().indices().prepareClose("test").get();
-        client().admin().indices().prepareUpdateSettings("test").setSettings(Settings.builder()
-                .put(IndexStoreModule.STORE_TYPE, type + "_fs").build()).get();
-        GetSettingsResponse getSettingsResponse = client().admin().indices().prepareGetSettings("test").get();
-        String actualType = getSettingsResponse.getSetting("test", IndexStoreModule.STORE_TYPE);
-        assertEquals(type + "_fs", actualType);
-
-        // now reopen and upgrade
-        client().admin().indices().prepareOpen("test").get();
-
-        getSettingsResponse = client().admin().indices().prepareGetSettings("test").get();
-        actualType = getSettingsResponse.getSetting("test", IndexStoreModule.STORE_TYPE);
-        assertEquals(type+"fs", actualType);
-    }
-
-}