diff --git a/x-pack/plugin/transform/qa/multi-node-tests/src/javaRestTest/java/org/elasticsearch/xpack/transform/integration/TransformChainIT.java b/x-pack/plugin/transform/qa/multi-node-tests/src/javaRestTest/java/org/elasticsearch/xpack/transform/integration/TransformChainIT.java
index dcf9eb1ae92af..706f6bc2041e6 100644
--- a/x-pack/plugin/transform/qa/multi-node-tests/src/javaRestTest/java/org/elasticsearch/xpack/transform/integration/TransformChainIT.java
+++ b/x-pack/plugin/transform/qa/multi-node-tests/src/javaRestTest/java/org/elasticsearch/xpack/transform/integration/TransformChainIT.java
@@ -21,6 +21,7 @@
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
 import java.util.concurrent.TimeUnit;
 
@@ -163,7 +164,7 @@ private void testChainedTransforms(final int numTransforms) throws Exception {
 
         List<String> transformIds = new ArrayList<>(numTransforms);
         // Create the chain of transforms. Previous transform's destination index becomes next transform's source index.
-        String transformIdPrefix = "my-transform-" + randomAlphaOfLength(4).toLowerCase() + "-" + numTransforms + "-";
+        String transformIdPrefix = "my-transform-" + randomAlphaOfLength(4).toLowerCase(Locale.ROOT) + "-" + numTransforms + "-";
         for (int i = 0; i < numTransforms; ++i) {
             String transformId = transformIdPrefix + i;
             transformIds.add(transformId);