diff --git a/src/autoreplace_cmd.cpp b/src/autoreplace_cmd.cpp
index 73f796cb73..654003e39e 100644
--- a/src/autoreplace_cmd.cpp
+++ b/src/autoreplace_cmd.cpp
@@ -815,6 +815,7 @@ CommandCost CmdSetAutoReplace(DoCommandFlag flags, GroupID id_g, EngineID old_en
 
 	if (Group::IsValidID(id_g) ? Group::Get(id_g)->owner != _current_company : !IsAllGroupID(id_g) && !IsDefaultGroupID(id_g)) return CMD_ERROR;
 	if (!Engine::IsValidID(old_engine_type)) return CMD_ERROR;
+	if (Group::IsValidID(id_g) && Group::Get(id_g)->vehicle_type != Engine::Get(old_engine_type)->type) return CMD_ERROR;
 
 	if (new_engine_type != INVALID_ENGINE) {
 		if (!Engine::IsValidID(new_engine_type)) return CMD_ERROR;