diff --git a/dvc/fs/base.py b/dvc/fs/base.py
index 4ab79a3fdc..b9aaeeff25 100644
--- a/dvc/fs/base.py
+++ b/dvc/fs/base.py
@@ -43,7 +43,6 @@ class FileSystem:
     REQUIRES: ClassVar[Dict[str, str]] = {}
     _JOBS = 4 * cpu_count()
 
-    CHECKSUM_DIR_SUFFIX = ".dir"
     HASH_JOBS = max(1, min(4, cpu_count() // 2))
     LIST_OBJECT_PAGE_SIZE = 1000
     TRAVERSE_WEIGHT_MULTIPLIER = 5
@@ -218,12 +217,6 @@ def reflink(self, from_info, to_info):
 
     # pylint: enable=unused-argument
 
-    @classmethod
-    def is_dir_hash(cls, hash_):
-        if not hash_:
-            return False
-        return hash_.endswith(cls.CHECKSUM_DIR_SUFFIX)
-
     def upload(
         self,
         from_info,
diff --git a/dvc/objects/db/__init__.py b/dvc/objects/db/__init__.py
index cabff21372..97ca9492ce 100644
--- a/dvc/objects/db/__init__.py
+++ b/dvc/objects/db/__init__.py
@@ -46,7 +46,6 @@ def get_index(odb) -> "ObjectDBIndexBase":
         hashlib.sha256(
             odb.fs.unstrip_protocol(odb.fs_path).encode("utf-8")
         ).hexdigest(),
-        odb.fs.CHECKSUM_DIR_SUFFIX,
     )
 
 
diff --git a/dvc/objects/db/base.py b/dvc/objects/db/base.py
index 46c2693e94..485a412742 100644
--- a/dvc/objects/db/base.py
+++ b/dvc/objects/db/base.py
@@ -372,17 +372,22 @@ def gc(self, used, jobs=None, cache_odb=None, shallow=True):
                     entry_obj.hash_info.value for _, entry_obj in tree
                 )
 
+        def _is_dir_hash(_hash):
+            from dvc.hash_info import HASH_DIR_SUFFIX
+
+            return _hash.endswith(HASH_DIR_SUFFIX)
+
         removed = False
         # hashes must be sorted to ensure we always remove .dir files first
         for hash_ in sorted(
             self.all(jobs, self.fs_path),
-            key=self.fs.is_dir_hash,
+            key=_is_dir_hash,
             reverse=True,
         ):
             if hash_ in used_hashes:
                 continue
             fs_path = self.hash_to_path(hash_)
-            if self.fs.is_dir_hash(hash_):
+            if _is_dir_hash(hash_):
                 # backward compatibility
                 # pylint: disable=protected-access
                 self._remove_unpacked_dir(hash_)
diff --git a/dvc/objects/db/index.py b/dvc/objects/db/index.py
index e928123520..4dc952a640 100644
--- a/dvc/objects/db/index.py
+++ b/dvc/objects/db/index.py
@@ -1,7 +1,7 @@
 import logging
 import os
 from abc import ABC, abstractmethod
-from typing import TYPE_CHECKING, Iterable, Optional, Set
+from typing import TYPE_CHECKING, Iterable, Set
 
 from ..errors import ObjectDBError
 
@@ -14,7 +14,9 @@
 class ObjectDBIndexBase(ABC):
     @abstractmethod
     def __init__(
-        self, tmp_dir: "StrPath", name: str, dir_suffix: Optional[str] = None
+        self,
+        tmp_dir: "StrPath",
+        name: str,
     ):
         pass
 
@@ -50,7 +52,9 @@ class ObjectDBIndexNoop(ObjectDBIndexBase):
     """No-op class for ODBs which are not indexed."""
 
     def __init__(
-        self, tmp_dir: "StrPath", name: str, dir_suffix: Optional[str] = None
+        self,
+        tmp_dir: "StrPath",
+        name: str,
     ):  # pylint: disable=super-init-not-called
         pass
 
@@ -80,7 +84,9 @@ class ObjectDBIndex(ObjectDBIndexBase):
     INDEX_DIR = "index"
 
     def __init__(
-        self, tmp_dir: "StrPath", name: str, dir_suffix: Optional[str] = None
+        self,
+        tmp_dir: "StrPath",
+        name: str,
     ):  # pylint: disable=super-init-not-called
         from diskcache import Index
 
@@ -92,10 +98,6 @@ def __init__(
         self.fs = LocalFileSystem()
         self.index = Index(self.index_dir)
 
-        if not dir_suffix:
-            dir_suffix = self.fs.CHECKSUM_DIR_SUFFIX
-        self.dir_suffix = dir_suffix
-
     def __iter__(self):
         return iter(self.index)
 
@@ -106,9 +108,6 @@ def dir_hashes(self):
         """Iterate over .dir hashes stored in the index."""
         yield from (hash_ for hash_, is_dir in self.index.items() if is_dir)
 
-    def is_dir_hash(self, hash_: str):
-        return hash_.endswith(self.dir_suffix)
-
     def clear(self):
         """Clear this index (to force re-indexing later)."""
         from diskcache import Timeout
diff --git a/tests/unit/remote/test_base.py b/tests/unit/remote/test_base.py
index 8156645712..b61c5532a5 100644
--- a/tests/unit/remote/test_base.py
+++ b/tests/unit/remote/test_base.py
@@ -135,11 +135,3 @@ def test_list_paths(dvc):
         walk_mock.assert_called_with(
             posixpath.join(path, "00", "0"), prefix=True
         )
-
-
-@pytest.mark.parametrize(
-    "hash_, result",
-    [(None, False), ("", False), ("3456.dir", True), ("3456", False)],
-)
-def test_is_dir_hash(hash_, result):
-    assert FileSystem.is_dir_hash(hash_) == result
diff --git a/tests/unit/remote/test_index.py b/tests/unit/remote/test_index.py
index 8195daf3d0..272aff5fa6 100644
--- a/tests/unit/remote/test_index.py
+++ b/tests/unit/remote/test_index.py
@@ -16,11 +16,6 @@ def test_init(dvc, index):
     assert str(index.index_dir) == os.path.join(dvc.tmp_dir, "index", "foo")
 
 
-def test_is_dir_hash(dvc, index):
-    assert index.is_dir_hash("foo.dir")
-    assert not index.is_dir_hash("foo")
-
-
 def test_roundtrip(dvc, index):
     expected_dir = {"1234.dir"}
     expected_file = {"5678"}