--- a/build/valgrind/valgrind.sh
+++ b/build/valgrind/valgrind.sh
@@ -22,17 +22,17 @@ cd $objdir
 if [ "`uname -m`" = "x86_64" ]; then
     _arch=64
 else
     _arch=32
 fi
 
 TOOLTOOL_MANIFEST=browser/config/tooltool-manifests/linux${_arch}/releng.manifest
 TOOLTOOL_SERVER=https://api.pub.build.mozilla.org/tooltool/
-(cd $srcdir; python /builds/tooltool.py --url $TOOLTOOL_SERVER --overwrite -m $TOOLTOOL_MANIFEST fetch ${TOOLTOOL_CACHE:+ -c ${TOOLTOOL_CACHE}}) || exit 2
+(cd $srcdir; ./mach artifact toolchain -v --tooltool-url $TOOLTOOL_SERVER --tooltool-manifest $TOOLTOOL_MANIFEST ${TOOLTOOL_CACHE:+ --cache-dir ${TOOLTOOL_CACHE}}) || exit 2
 
 # Note: an exit code of 2 turns the job red on TBPL.
 MOZCONFIG=$srcdir/browser/config/mozconfigs/linux${_arch}/valgrind make -f $srcdir/client.mk configure || exit 2
 make -j4 || exit 2
 make package || exit 2
 
 # We need to set MOZBUILD_STATE_PATH so that |mach| skips its first-run
 # initialization step and actually runs the |valgrind-test| command.