diff --git a/selfdrive/car/__init__.py b/selfdrive/car/__init__.py
index 7f47abbf98..fe4bacd62f 100644
--- a/selfdrive/car/__init__.py
+++ b/selfdrive/car/__init__.py
@@ -1,6 +1,6 @@
 # functions common among cars
 from collections import namedtuple
-from dataclasses import dataclass, field
+from dataclasses import dataclass
 from enum import IntFlag, ReprEnum
 from dataclasses import replace
 
@@ -250,12 +250,12 @@ CarInfos = CarInfo | list[CarInfo]
 
 @dataclass(frozen=True, kw_only=True)
 class CarSpecs:
-  mass: float
+  mass: float  # kg, curb weight
   wheelbase: float
   steerRatio: float
-  centerToFrontRatio: float = field(default=0.5)
-  minSteerSpeed: float = field(default=0.)
-  minEnableSpeed: float = field(default=-1.)
+  centerToFrontRatio: float = 0.5
+  minSteerSpeed: float = 0.0
+  minEnableSpeed: float = -1.0
 
 
 @dataclass(order=True)
diff --git a/selfdrive/car/volkswagen/values.py b/selfdrive/car/volkswagen/values.py
index 3e4a742224..065a340928 100644
--- a/selfdrive/car/volkswagen/values.py
+++ b/selfdrive/car/volkswagen/values.py
@@ -112,17 +112,21 @@ class CANBUS:
 class VolkswagenFlags(IntFlag):
   STOCK_HCA_PRESENT = 1
 
+
 @dataclass
 class VolkswagenMQBPlatformConfig(PlatformConfig):
   dbc_dict: DbcDict = field(default_factory=lambda: dbc_dict('vw_mqb_2010', None))
 
+
 @dataclass
 class VolkswagenPQPlatformConfig(PlatformConfig):
   dbc_dict: DbcDict = field(default_factory=lambda: dbc_dict('vw_golf_mk4', None))
 
+
 @dataclass(frozen=True, kw_only=True)
 class VolkswagenCarSpecs(CarSpecs):
-  steerRatio: float = field(default=15.6)
+  steerRatio: float = 15.6
+
 
 class Footnote(Enum):
   KAMIQ = CarFootnote(
@@ -158,6 +162,7 @@ class VWCarInfo(CarInfo):
     if CP.carFingerprint in (CAR.CRAFTER_MK2, CAR.TRANSPORTER_T61):
       self.car_parts = CarParts([Device.threex_angled_mount, CarHarness.j533])
 
+
 # Check the 7th and 8th characters of the VIN before adding a new CAR. If the
 # chassis code is already listed below, don't add a new CAR, just add to the
 # FW_VERSIONS for that existing CAR.
@@ -353,6 +358,7 @@ class CAR(Platforms):
     specs=VolkswagenCarSpecs(mass=1505, wheelbase=2.84),
   )
 
+
 PQ_CARS = {CAR.PASSAT_NMS, CAR.SHARAN_MK2}
 
 # All supported cars should return FW from the engine, srs, eps, and fwdRadar. Cars