--- a/testing/taskcluster/tasks/tests/b2g_emulator_xpcshell.yml
+++ b/testing/taskcluster/tasks/tests/b2g_emulator_xpcshell.yml
@@ -2,16 +2,17 @@
 $inherits:
   from: 'tasks/test.yml'
 task:
   metadata:
     name: '[TC] XPCShell'
     description: XPCShell test run
 
   payload:
+    maxRunTime: 6000
     command:
       - entrypoint
       - >
         python ./mozharness/scripts/b2g_emulator_unittest.py
         --config-file ./mozharness/configs/b2g/emulator_automation_config.py
         --config-file ./mozharness_configs/emulator_override.py
         --download-symbols ondemand
         --test-suite xpcshell

--- a/testing/taskcluster/tasks/tests/b2g_emulator_xpcshell_chunked.yml
+++ b/testing/taskcluster/tasks/tests/b2g_emulator_xpcshell_chunked.yml
@@ -2,16 +2,17 @@
 $inherits:
   from: 'tasks/test.yml'
 task:
   metadata:
     name: '[TC] XPCShell'
     description: XPCShell test run {{chunk}}
 
   payload:
+    maxRunTime: 6000
     command:
       - entrypoint
       - >
         python ./mozharness/scripts/b2g_emulator_unittest.py
         --config-file ./mozharness/configs/b2g/emulator_automation_config.py
         --config-file ./mozharness_configs/emulator_override.py
         --download-symbols ondemand
         --test-suite xpcshell