--- a/testing/mozharness/configs/single_locale/alder.py
+++ b/testing/mozharness/configs/single_locale/alder.py
@@ -18,17 +18,16 @@
 
 import os
 
 config = {
     "nightly_build": True,
     "branch": "alder",
     "en_us_binary_url": "http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/latest-mozilla-central/",
     "update_channel": "nightly",
-    "latest_mar_dir": '/pub/mozilla.org/firefox/nightly/latest-mozilla-central-l10n',
 
     # l10n
     "hg_l10n_base": "https://hg.mozilla.org/l10n-central",
 
     # mar
     "mar_tools_url": os.environ.get(
         "MAR_TOOLS_URL",
         # Buildbot l10n fetches from ftp rather than setting an environ var

--- a/testing/mozharness/configs/single_locale/ash.py
+++ b/testing/mozharness/configs/single_locale/ash.py
@@ -18,17 +18,16 @@
 
 import os
 
 config = {
     "nightly_build": True,
     "branch": "ash",
     "en_us_binary_url": "http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/latest-mozilla-central/",
     "update_channel": "nightly",
-    "latest_mar_dir": '/pub/mozilla.org/firefox/nightly/latest-mozilla-central-l10n',
 
     # l10n
     "hg_l10n_base": "https://hg.mozilla.org/l10n-central",
 
     # mar
     "mar_tools_url": os.environ.get(
         "MAR_TOOLS_URL",
         # Buildbot l10n fetches from ftp rather than setting an environ var

--- a/testing/mozharness/configs/single_locale/date.py
+++ b/testing/mozharness/configs/single_locale/date.py
@@ -1,16 +1,15 @@
 import os
 
 config = {
     "nightly_build": True,
     "branch": "date",
     "en_us_binary_url": "http://archive.mozilla.org/pub/firefox/nightly/latest-mozilla-central",
     "update_channel": "nightly-date",
-    "latest_mar_dir": '/pub/firefox/nightly/latest-date-l10n',
 
     # l10n
     "hg_l10n_base": "https://hg.mozilla.org/l10n-central",
 
     # mar
     "mar_tools_url": os.environ.get(
         "MAR_TOOLS_URL",
         # Buildbot l10n fetches from ftp rather than setting an environ var

--- a/testing/mozharness/configs/single_locale/dev-mozilla-beta.py
+++ b/testing/mozharness/configs/single_locale/dev-mozilla-beta.py
@@ -1,19 +1,16 @@
 config = {
     "branch": "date",
     "nightly_build": True,
     "update_channel": "beta-dev",
 
     # l10n
     "hg_l10n_base": "https://hg.mozilla.org/releases/l10n/mozilla-beta",
 
-    # mar
-    "latest_mar_dir": "fake_kill_me",
-
     # repositories
     # staging beta dev releases use date repo for now
     "mozilla_dir": "date",
     "repos": [{
         "vcs": "hg",
         "repo": "https://hg.mozilla.org/build/tools",
         "branch": "default",
         "dest": "tools",

--- a/testing/mozharness/configs/single_locale/dev-mozilla-release.py
+++ b/testing/mozharness/configs/single_locale/dev-mozilla-release.py
@@ -1,13 +1,12 @@
 config = {
     "branch": "jamun",
     "nightly_build": True,
     "update_channel": "release-dev",
-    "latest_mar_dir": 'fake_kill_me',
 
     # l10n
     "hg_l10n_base": "https://hg.mozilla.org/releases/l10n/mozilla-release",
 
     # repositories
     # staging release uses jamun
     "mozilla_dir": "jamun",
     "repos": [{

--- a/testing/mozharness/configs/single_locale/mozilla-aurora.py
+++ b/testing/mozharness/configs/single_locale/mozilla-aurora.py
@@ -1,16 +1,15 @@
 import os
 
 config = {
     "nightly_build": True,
     "branch": "mozilla-aurora",
     "en_us_binary_url": "http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/latest-mozilla-aurora/",
     "update_channel": "aurora",
-    "latest_mar_dir": '/pub/mozilla.org/firefox/nightly/latest-mozilla-aurora-l10n',
 
     # l10n
     "hg_l10n_base": "https://hg.mozilla.org/releases/l10n/mozilla-aurora",
 
     # mar
     "mar_tools_url": os.environ.get(
         "MAR_TOOLS_URL",
         # Buildbot l10n fetches from ftp rather than setting an environ var

--- a/testing/mozharness/configs/single_locale/mozilla-beta.py
+++ b/testing/mozharness/configs/single_locale/mozilla-beta.py
@@ -1,14 +1,13 @@
 config = {
     "nightly_build": True,
     "branch": "mozilla-beta",
     "en_us_binary_url": "http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/latest-mozilla-beta/",
     "update_channel": "beta",
-    "latest_mar_dir": '/pub/mozilla.org/firefox/nightly/latest-mozilla-beta-l10n',
 
     # l10n
     "hg_l10n_base": "https://hg.mozilla.org/releases/l10n/mozilla-beta",
 
     # repositories
     "mozilla_dir": "mozilla-beta",
     "repos": [{
         "vcs": "hg",

--- a/testing/mozharness/configs/single_locale/mozilla-central.py
+++ b/testing/mozharness/configs/single_locale/mozilla-central.py
@@ -1,16 +1,15 @@
 import os
 
 config = {
     "nightly_build": True,
     "branch": "mozilla-central",
     "en_us_binary_url": "http://archive.mozilla.org/pub/firefox/nightly/latest-mozilla-central",
     "update_channel": "nightly",
-    "latest_mar_dir": '/pub/firefox/nightly/latest-mozilla-central-l10n',
 
     # l10n
     "hg_l10n_base": "https://hg.mozilla.org/l10n-central",
 
     # mar
     "mar_tools_url": os.environ.get(
         "MAR_TOOLS_URL",
         # Buildbot l10n fetches from ftp rather than setting an environ var

--- a/testing/mozharness/configs/single_locale/mozilla-release.py
+++ b/testing/mozharness/configs/single_locale/mozilla-release.py
@@ -1,14 +1,13 @@
 config = {
     "nightly_build": True,
     "branch": "mozilla-release",
     "en_us_binary_url": "http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/latest-mozilla-release/",
     "update_channel": "release",
-    "latest_mar_dir": '/pub/mozilla.org/firefox/nightly/latest-mozilla-release-l10n',
 
     # l10n
     "hg_l10n_base": "https://hg.mozilla.org/releases/l10n/mozilla-release",
 
     # repositories
     "mozilla_dir": "mozilla-release",
     "repos": [{
         "vcs": "hg",

--- a/testing/mozharness/configs/single_locale/try.py
+++ b/testing/mozharness/configs/single_locale/try.py
@@ -1,16 +1,15 @@
 import os
 
 config = {
     "nightly_build": False,
     "branch": "try",
     "en_us_binary_url": "http://archive.mozilla.org/pub/firefox/nightly/latest-mozilla-central",
     "update_channel": "nightly",
-    "latest_mar_dir": '/pub/firefox/nightly/latest-mozilla-central-l10n',
     "update_gecko_source_to_enUS": False,
 
     # l10n
     "hg_l10n_base": "https://hg.mozilla.org/l10n-central",
 
     # mar
     "mar_tools_url": os.environ.get(
         "MAR_TOOLS_URL",

--- a/testing/mozharness/mozharness/mozilla/building/buildbase.py
+++ b/testing/mozharness/mozharness/mozilla/building/buildbase.py
@@ -930,21 +930,16 @@ or run without that action (ie: --no-{ac
                 mach_env['UPLOAD_USER'] = mach_env['UPLOAD_USER'] % {
                     'stage_username': c['stage_username']
                 }
             if 'UPLOAD_SSH_KEY' in mach_env and 'stage_ssh_key' in c:
                 mach_env['UPLOAD_SSH_KEY'] = mach_env['UPLOAD_SSH_KEY'] % {
                     'stage_ssh_key': c['stage_ssh_key']
                 }
 
-        if self.query_is_nightly():
-            mach_env['LATEST_MAR_DIR'] = c['latest_mar_dir'] % {
-                'branch': self.branch
-            }
-
         # this prevents taskcluster from overwriting the target files with
         # the multilocale files. Put everything from the en-US build in a
         # separate folder.
         if multiLocale and self.config.get('taskcluster_nightly'):
             if 'UPLOAD_PATH' in mach_env:
                 mach_env['UPLOAD_PATH'] = os.path.join(mach_env['UPLOAD_PATH'],
                                                        'en-US')
 

--- a/testing/mozharness/scripts/desktop_l10n.py
+++ b/testing/mozharness/scripts/desktop_l10n.py
@@ -411,17 +411,16 @@ class DesktopSingleLocale(LocalesMixin, 
         }
         if config['branch'] == 'try':
             replace_dict.update({
                 'who': self.query_who(),
                 'revision': self._query_revision(),
             })
         upload_env = self.query_env(partial_env=config.get("upload_env"),
                                     replace_dict=replace_dict)
-        upload_env['LATEST_MAR_DIR'] = config['latest_mar_dir']
         # check if there are any extra option from the platform configuration
         # and append them to the env
 
         if 'upload_env_extra' in config:
             for extra in config['upload_env_extra']:
                 upload_env[extra] = config['upload_env_extra'][extra]
 
         self.upload_env = upload_env

--- a/testing/mozharness/scripts/fx_desktop_build.py
+++ b/testing/mozharness/scripts/fx_desktop_build.py
@@ -70,17 +70,16 @@ class FxDesktopBuild(BuildScript, TryToo
                     "%(objdir)s/dist/firefox-*",
                     "%(objdir)s/dist/fennec*",
                     "%(objdir)s/dist/seamonkey*",
                     "%(objdir)s/dist/thunderbird*",
                     "%(objdir)s/dist/install/sea/*.exe"
                 ],
                 'stage_product': 'firefox',
                 'platform_supports_post_upload_to_latest': True,
-                'latest_mar_dir': '/pub/mozilla.org/firefox/nightly/latest-%(branch)s',
                 'build_resources_path': '%(abs_src_dir)s/obj-firefox/.mozbuild/build_resources.json',
                 'nightly_promotion_branches': ['mozilla-central', 'mozilla-aurora'],
 
                 # try will overwrite these
                 'clone_with_purge': False,
                 'clone_by_revision': False,
                 'tinderbox_build_dir': None,
                 'to_tinderbox_dated': True,