--- a/taskcluster/ci/legacy/tasks/builds/dbg_linux64-asan.yml
+++ b/taskcluster/ci/legacy/tasks/builds/dbg_linux64-asan.yml
@@ -21,10 +21,11 @@ task:
   extra:
     treeherder:
       groupSymbol: tc
       groupName: Submitted by taskcluster
       symbol: Bd
       machine:
         # see https://github.com/mozilla/treeherder/blob/master/ui/js/values.js
         platform: linux64
+      tier: 1
       collection:
         asan: true

--- a/taskcluster/ci/legacy/tasks/builds/dbg_linux64.yml
+++ b/taskcluster/ci/legacy/tasks/builds/dbg_linux64.yml
@@ -18,11 +18,12 @@ task:
     env:
       MH_CUSTOM_BUILD_VARIANT_CFG: 'debug'
 
   extra:
     treeherder:
       groupSymbol: tc
       groupName: Submitted by taskcluster
       symbol: B
+      tier: 1
       collection:
         debug: true
 

--- a/taskcluster/ci/legacy/tasks/builds/opt_linux64-asan.yml
+++ b/taskcluster/ci/legacy/tasks/builds/opt_linux64-asan.yml
@@ -21,10 +21,11 @@ task:
   extra:
     treeherder:
       groupSymbol: tc
       groupName: Submitted by taskcluster
       machine:
         # see https://github.com/mozilla/treeherder/blob/master/ui/js/values.js
         platform: linux64
       symbol: Bo
+      tier: 1
       collection:
         asan: true

--- a/taskcluster/ci/legacy/tasks/builds/opt_linux64.yml
+++ b/taskcluster/ci/legacy/tasks/builds/opt_linux64.yml
@@ -14,9 +14,9 @@ task:
 
   workerType: opt-linux64
 
   extra:
     treeherder:
       groupSymbol: tc
       groupName: Submitted by taskcluster
       symbol: B
-
+      tier: 2