diff --git a/src/ride/track.c b/src/ride/track.c
index b1c03c105a..cfeee024c7 100644
--- a/src/ride/track.c
+++ b/src/ride/track.c
@@ -3036,6 +3036,8 @@ int save_track_design(uint8 rideIndex){
 		return 1;
 	}
 
+	path_set_extension(path, "TD6");
+
 	save_track_to_file(RCT2_ADDRESS(0x009D8178, rct_track_td6), path);
 
 	ride_list_item item = { .type = 0xFC, .entry_index = 0 };