diff --git a/src/TwitterOAuth.php b/src/TwitterOAuth.php
index 5a7d7979..72e8faab 100644
--- a/src/TwitterOAuth.php
+++ b/src/TwitterOAuth.php
@@ -240,17 +240,21 @@ public function get(string $path, array $parameters = [])
     /**
      * Make POST requests to the API.
      *
-     * @param string $path
-     * @param array  $parameters
-     * @param bool   $json
+     * @param string    $path
+     * @param array     $parameters
+     * @param bool|null $json
      *
      * @return array|object
      */
     public function post(
         string $path,
-        array $parameters = [],
-        bool $json = false,
+        array $parameters = [],x
+        bool|null $json = null,
     ) {
+        if (is_null($json)) {
+            $json = $this->useJsonBody();
+        }
+
         return $this->http('POST', self::API_HOST, $path, $parameters, $json);
     }
 
@@ -270,17 +274,21 @@ public function delete(string $path, array $parameters = [])
     /**
      * Make PUT requests to the API.
      *
-     * @param string $path
-     * @param array  $parameters
-     * @param bool   $json
+     * @param string    $path
+     * @param array     $parameters
+     * @param bool|null $json
      *
      * @return array|object
      */
     public function put(
         string $path,
         array $parameters = [],
-        bool $json = false,
+        bool|null $json = null,
     ) {
+        if (is_null($json)) {
+            $json = $this->useJsonBody();
+        }
+
         return $this->http('PUT', self::API_HOST, $path, $parameters, $json);
     }
 
@@ -467,6 +475,19 @@ private function extension()
         ][$this->apiVersion];
     }
 
+    /**
+     * Default content type for sending data.
+     *
+     * @return bool
+     */
+    private function useJsonBody()
+    {
+        return [
+            '1.1' => false,
+            '2' => true,
+        ][$this->apiVersion];
+    }
+
     /**
      * @param string $method
      * @param string $host