diff --git a/wire-gson-support/src/main/java/com/squareup/wire/MessageTypeAdapter.java b/wire-gson-support/src/main/java/com/squareup/wire/MessageTypeAdapter.java
index 728993eaf4..d7f0eea700 100644
--- a/wire-gson-support/src/main/java/com/squareup/wire/MessageTypeAdapter.java
+++ b/wire-gson-support/src/main/java/com/squareup/wire/MessageTypeAdapter.java
@@ -32,10 +32,6 @@
 import okio.Buffer;
 import okio.ByteString;
 
-import static com.squareup.wire.FieldEncoding.FIXED32;
-import static com.squareup.wire.FieldEncoding.FIXED64;
-import static com.squareup.wire.FieldEncoding.LENGTH_DELIMITED;
-import static com.squareup.wire.FieldEncoding.VARINT;
 import static com.squareup.wire.WireField.Label;
 import static java.util.Collections.unmodifiableMap;
 
@@ -44,18 +40,6 @@ class MessageTypeAdapter<M extends Message<M, B>, B extends Message.Builder<M, B
 
   private final Class<M> messageType;
 
-  enum UnknownFieldType {
-    VARINT, FIXED32, FIXED64, LENGTH_DELIMITED;
-
-    public static UnknownFieldType of(String name) {
-      if ("varint".equals(name)) return VARINT;
-      if ("fixed32".equals(name)) return FIXED32;
-      if ("fixed64".equals(name)) return FIXED64;
-      if ("length-delimited".equals(name)) return LENGTH_DELIMITED;
-      throw new IllegalArgumentException("Unknown type " + name);
-    }
-  }
-
   // 2^64, used to convert sint64 values >= 2^63 to unsigned decimal form
   private static final BigInteger POWER_64 = new BigInteger("18446744073709551616");
 
@@ -172,7 +156,7 @@ private void emitUint64(Long value, JsonWriter out) throws IOException {
         continue;
       }
 
-      parseUnknownField(in, builder, Integer.parseInt(name));
+      in.skipValue();
     }
 
     in.endObject();
@@ -195,34 +179,6 @@ private Object parseValue(Label label, Type valueType, JsonElement valueElement)
     }
   }
 
-  private void parseUnknownField(JsonReader in, B builder, int tag) throws IOException {
-    in.beginArray();
-    UnknownFieldType type = UnknownFieldType.of(in.nextString());
-    while (in.peek() != JsonToken.END_ARRAY) {
-      switch (type) {
-        case VARINT:
-          long varint = in.nextLong();
-          builder.addUnknownField(tag, VARINT, varint);
-          break;
-        case FIXED32:
-          int fixed32 = in.nextInt();
-          builder.addUnknownField(tag, FIXED32, fixed32);
-          break;
-        case FIXED64:
-          long fixed64 = in.nextLong();
-          builder.addUnknownField(tag, FIXED64, fixed64);
-          break;
-        case LENGTH_DELIMITED:
-          ByteString byteString = ByteString.decodeBase64(in.nextString());
-          builder.addUnknownField(tag, LENGTH_DELIMITED, byteString);
-          break;
-        default:
-          throw new AssertionError("Unknown field type " + type);
-      }
-    }
-    in.endArray();
-  }
-
   private Object readJson(Type valueType, JsonElement element) {
     return gson.fromJson(element, valueType);
   }
diff --git a/wire-gson-support/src/test/java/com/squareup/wire/GsonTest.java b/wire-gson-support/src/test/java/com/squareup/wire/GsonTest.java
index 5b2388f7ca..df49a03ce5 100644
--- a/wire-gson-support/src/test/java/com/squareup/wire/GsonTest.java
+++ b/wire-gson-support/src/test/java/com/squareup/wire/GsonTest.java
@@ -277,9 +277,10 @@ public void testGson() {
     String json = gson.toJson(allTypes);
     assertThat(json).isEqualTo("{" + JSON_BASE + JSON_UNKNOWN_FIELDS + "}");
 
+    AllTypes allTypesWithKnownFields = allTypes.withoutUnknownFields();
     AllTypes parsed = gson.fromJson(json, AllTypes.class);
-    assertThat(parsed).isEqualTo(allTypes);
-    assertThat(parsed.toString()).isEqualTo(allTypes.toString());
-    assertThat(gson.toJson(parsed)).isEqualTo(gson.toJson(allTypes));
+    assertThat(parsed).isEqualTo(allTypesWithKnownFields);
+    assertThat(parsed.toString()).isEqualTo(allTypesWithKnownFields.toString());
+    assertThat(gson.toJson(parsed)).isEqualTo(gson.toJson(allTypesWithKnownFields));
   }
 }