Index: usr.sbin/bsdinstall/scripts/auto
===================================================================
--- usr.sbin/bsdinstall/scripts/auto
+++ usr.sbin/bsdinstall/scripts/auto
@@ -447,6 +447,43 @@
 	esac
 }
 
+check_wheel() {
+
+	WHEEL_MEMBERS=$(chroot $BSDINSTALL_CHROOT pw group show wheel)
+	if [ "$WHEEL_MEMBERS" = "wheel:*:0:root" ]; then
+		SSH_ENABLE=$(sysrc -n -f $BSDINSTALL_TMPETC/rc.conf.services sshd_enable)
+		if [ "$SSH_ENABLE" = "YES" ]; then
+			exec 3>&1
+			WHEEL_QUESTION=$(dialog --backtitle "FreeBSD Installer" \
+			    --title "Configuration Validation" --no-cancel --menu \
+			    "You have enabled SSH but not added any users to the wheel group. You will not be able to gain administrative privileges as a regular user if the user is not in the wheel group." 0 0 0 \
+				"Add User" "Add a user to the system" \
+				"Invite User" "Add an existing user to the wheel group" \
+				"Continue Anyway" "No remote root access" 2>&1 1>&3)
+			exec 3>&-
+
+			f_dprintf "%s: check_wheel: %s" "$0" "$WHEEL_QUESTION"
+			case "$WHEEL_QUESTION" in
+			"Add User")
+				bsdinstall adduser
+				check_wheel
+				;;
+			"Invite User")
+				bsdinstall wheelinvite
+				check_wheel
+				;;
+			"Continue anyway")
+				;;
+			esac
+		fi
+	fi
+}
+
+# Remind the user if they forgot to add a user to the wheel group (if SSHd is enabled)
+if f_interactive; then
+	check_wheel
+fi
+
 # Allow user to change his mind
 finalconfig
 
Index: usr.sbin/bsdinstall/scripts/wheelinvite
===================================================================
--- /dev/null
+++ usr.sbin/bsdinstall/scripts/wheelinvite
@@ -0,0 +1,39 @@
+#!/bin/sh
+#-
+# Copyright (c) 2018 Allan Jude <allanjude@freebsd.org>
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+#
+# $FreeBSD$
+
+clear
+echo "FreeBSD Installer"
+echo "========================"
+echo
+echo -n "User to invite to the wheel group: "
+read invite_user
+echo
+f_dprintf "%s: wheelinvite: %s" "$0" "$invite_user"
+if [ -n "$invite_user" ]; then
+	chroot $BSDINSTALL_CHROOT pw group mod wheel -m $invite_user
+fi