--- a/taskcluster/ci/fetch/toolchains.yml
+++ b/taskcluster/ci/fetch/toolchains.yml
@@ -209,17 +209,17 @@ grcov-osx-x86_64:
   treeherder:
     symbol: grcov-osx-x86_64
   run:
     using: fetch-url
     url: https://github.com/mozilla/grcov/releases/download/v0.2.3/grcov-osx-x86_64.tar.bz2
     sha256: 3db4ef6c0dfaf35d39c9cacf19c60c482dae9413b5fe3bf343fa26667451c893
     size: 919638
 
-grcov-win-i686:
+grcov-win-x86_64:
   description: grcov binary release
   treeherder:
-    symbol: grcov-win-i686
+    symbol: grcov-win-x86_64
   run:
     using: fetch-url
-    url: https://github.com/mozilla/grcov/releases/download/v0.2.3/grcov-win-i686.tar.bz2
-    sha256: 87c3c22cd1bb99d9c41b6a6f9e20b6c655a580021776f1a532297f5e8315ad9b
-    size: 919079
+    url: https://github.com/mozilla/grcov/releases/download/v0.2.3/grcov-win-x86_64.tar.bz2
+    sha256: baede397959ec6f5e0c9630c8e9e1e59ebe723ec95acea9bb204511a886e0f2f
+    size: 1009309

--- a/taskcluster/taskgraph/transforms/tests.py
+++ b/taskcluster/taskgraph/transforms/tests.py
@@ -724,17 +724,17 @@ def enable_code_coverage(config, tests):
             test['optimization'] = None
 
             # Add a fetch task for the grcov binary.
             if 'linux' in test['build-platform']:
                 test['fetches'] = ['grcov-linux-x86_64']
             elif 'osx' in test['build-platform']:
                 test['fetches'] = ['grcov-osx-x86_64']
             elif 'win' in test['build-platform']:
-                test['fetches'] = ['grcov-win-i686']
+                test['fetches'] = ['grcov-win-x86_64']
 
             if 'talos' in test['test-name']:
                 test['max-run-time'] = 7200
                 if 'linux' in test['build-platform']:
                     test['docker-image'] = {"in-tree": "desktop1604-test"}
                 test['mozharness']['extra-options'].append('--add-option')
                 test['mozharness']['extra-options'].append('--cycles,1')
                 test['mozharness']['extra-options'].append('--add-option')