diff --git a/docs/libcurl/opts/CURLOPT_MAXLIFETIME_CONN.md b/docs/libcurl/opts/CURLOPT_MAXLIFETIME_CONN.md
index b29e61a2c3..8c1fbf82f8 100644
--- a/docs/libcurl/opts/CURLOPT_MAXLIFETIME_CONN.md
+++ b/docs/libcurl/opts/CURLOPT_MAXLIFETIME_CONN.md
@@ -35,16 +35,18 @@ connection to have to be considered for reuse for this request.
 
 libcurl features a connection cache that holds previously used connections.
 When a new request is to be done, libcurl considers any connection that
-matches for reuse. The CURLOPT_MAXLIFETIME_CONN(3) limit prevents
-libcurl from trying too old connections for reuse. This can be used for
-client-side load balancing. If a connection is found in the cache that is
-older than this set *maxlifetime*, it is instead marked for closure.
+matches for reuse. The CURLOPT_MAXLIFETIME_CONN(3) limit prevents libcurl from
+trying too old connections for reuse. This can be used for client-side load
+balancing. If a connection is found in the cache that is older than this set
+*maxlifetime*, it is instead marked for closure.
 
-If set to 0, this behavior is disabled: all connections are eligible for reuse.
+If set to 0, this behavior is disabled: all connections are eligible for
+reuse.
 
 # DEFAULT
 
-0 seconds (i.e., disabled)
+24 hours (since 8.17.0). Before that, the default was 0 seconds (i.e.,
+disabled)
 
 # %PROTOCOLS%
 
diff --git a/lib/url.c b/lib/url.c
index 45d44bac73..283da6d68b 100644
--- a/lib/url.c
+++ b/lib/url.c
@@ -488,7 +488,7 @@ CURLcode Curl_init_userdefined(struct Curl_easy *data)
   set->upkeep_interval_ms = CURL_UPKEEP_INTERVAL_DEFAULT;
   set->maxconnects = DEFAULT_CONNCACHE_SIZE; /* for easy handles */
   set->conn_max_idle_ms = 118 * 1000;
-  set->conn_max_age_ms = 0;
+  set->conn_max_age_ms = 24 * 3600 * 1000;
   set->http09_allowed = FALSE;
   set->httpwant = CURL_HTTP_VERSION_NONE
     ;
diff --git a/lib/urldata.h b/lib/urldata.h
index cf181af641..a0ee614da8 100644
--- a/lib/urldata.h
+++ b/lib/urldata.h
@@ -1390,9 +1390,9 @@ struct UserDefined {
   void *progress_client; /* pointer to pass to the progress callback */
   void *ioctl_client;   /* pointer to pass to the ioctl callback */
   timediff_t conn_max_idle_ms; /* max idle time to allow a connection that
-                           is to be reused */
+                                  is to be reused */
   timediff_t conn_max_age_ms; /* max time since creation to allow a
-                            connection that is to be reused */
+                                 connection that is to be reused */
   curl_off_t filesize;  /* size of file to upload, -1 means unknown */
   long low_speed_limit; /* bytes/second */
   long low_speed_time;  /* number of seconds */