diff --git a/frontend/src/components/shared/Sidebar.tsx b/frontend/src/components/shared/Sidebar.tsx
index d82d233..b4e0e36 100644
--- a/frontend/src/components/shared/Sidebar.tsx
+++ b/frontend/src/components/shared/Sidebar.tsx
@@ -1,7 +1,6 @@
-import { useState, useMemo } from 'react';
+import { useMemo } from 'react';
 import {
   Box,
-  Collapse,
   Drawer,
   IconButton,
   List,
@@ -23,8 +22,6 @@ import {
   AdminPanelSettings,
   Settings,
   Menu as MenuIcon,
-  ExpandMore,
-  ExpandLess,
   LocalShipping,
   BugReport,
   BookOnline,
@@ -37,31 +34,17 @@ import { useNavigate, useLocation } from 'react-router-dom';
 import { useQuery } from '@tanstack/react-query';
 import { useLayout, DRAWER_WIDTH, DRAWER_WIDTH_COLLAPSED } from '../../contexts/LayoutContext';
 import { usePermissionContext } from '../../contexts/PermissionContext';
-import { vehiclesApi } from '../../services/vehicles';
 import { preferencesApi } from '../../services/settings';
 
 export { DRAWER_WIDTH, DRAWER_WIDTH_COLLAPSED };
 
-interface SubItem {
-  text: string;
-  path: string;
-}
-
 interface NavigationItem {
   text: string;
   icon: JSX.Element;
   path: string;
-  subItems?: SubItem[];
   permission?: string;
 }
 
-const adminSubItems: SubItem[] = [
-  { text: 'Information', path: '/admin?tab=0' },
-  { text: 'System Mitteilungen', path: '/admin?tab=1' },
-  { text: 'Tool Zugriff', path: '/admin?tab=2' },
-  { text: 'Daten', path: '/admin?tab=3' },
-];
-
 const baseNavigationItems: NavigationItem[] = [
   {
     text: 'Dashboard',
@@ -125,18 +108,12 @@ const baseNavigationItems: NavigationItem[] = [
     text: 'Bestellungen',
     icon: <LocalShipping />,
     path: '/bestellungen',
-    subItems: [
-      { text: 'Übersicht', path: '/bestellungen?tab=0' },
-      { text: 'Lieferanten', path: '/bestellungen?tab=1' },
-      { text: 'Katalog', path: '/bestellungen?tab=2' },
-    ],
     permission: 'bestellungen:view',
   },
   {
     text: 'Interne Bestellungen',
     icon: <Build />,
     path: '/ausruestungsanfrage',
-    // subItems computed dynamically in navigationItems useMemo
     permission: 'ausruestungsanfrage:view',
   },
   {
@@ -149,19 +126,12 @@ const baseNavigationItems: NavigationItem[] = [
     text: 'Buchhaltung',
     icon: <AccountBalanceIcon />,
     path: '/buchhaltung',
-    subItems: [
-      { text: 'Übersicht',       path: '/buchhaltung?tab=0' },
-      { text: 'Transaktionen',   path: '/buchhaltung?tab=1' },
-      { text: 'Konten',          path: '/buchhaltung?tab=2' },
-      { text: 'Haushaltspläne',  path: '/haushaltsplan' },
-    ],
     permission: 'buchhaltung:view',
   },
   {
     text: 'Issues',
     icon: <BugReport />,
     path: '/issues',
-    // subItems computed dynamically in navigationItems useMemo
     permission: 'issues:view_own',
   },
 ];
@@ -170,7 +140,6 @@ const adminItem: NavigationItem = {
   text: 'Admin',
   icon: <AdminPanelSettings />,
   path: '/admin',
-  subItems: adminSubItems,
 };
 
 const adminSettingsItem: NavigationItem = {
@@ -190,13 +159,6 @@ function Sidebar({ mobileOpen, onMobileClose }: SidebarProps) {
   const { sidebarCollapsed, toggleSidebar } = useLayout();
   const { hasPermission } = usePermissionContext();
 
-  // Fetch vehicle list for dynamic dropdown sub-items
-  const { data: vehicleList } = useQuery({
-    queryKey: ['vehicles', 'sidebar'],
-    queryFn: () => vehiclesApi.getAll(),
-    staleTime: 2 * 60 * 1000,
-  });
-
   const { data: preferences } = useQuery({
     queryKey: ['user-preferences'],
     queryFn: preferencesApi.get,
@@ -205,88 +167,22 @@ function Sidebar({ mobileOpen, onMobileClose }: SidebarProps) {
 
   const menuOrder: string[] = (preferences?.menuOrder as string[] | undefined) ?? [];
 
-  const vehicleSubItems: SubItem[] = useMemo(
-    () => {
-      const items: SubItem[] = [
-        { text: 'Übersicht', path: '/fahrzeuge?tab=0' },
-      ];
-      (vehicleList ?? []).forEach((v) => {
-        items.push({
-          text: v.bezeichnung ?? v.kurzname,
-          path: `/fahrzeuge/${v.id}`,
-        });
-      });
-      if (hasPermission('fahrzeuge:edit')) {
-        items.push({ text: 'Einstellungen', path: '/fahrzeuge?tab=1' });
-      }
-      return items;
-    },
-    [vehicleList, hasPermission],
-  );
-
   const navigationItems = useMemo((): NavigationItem[] => {
-    const fahrzeugeItem: NavigationItem = {
-      text: 'Fahrzeuge',
-      icon: <DirectionsCar />,
-      path: '/fahrzeuge',
-      subItems: vehicleSubItems.length > 0 ? vehicleSubItems : undefined,
-      permission: 'fahrzeuge:view',
-    };
-
-    // Build Ausrüstungsanfrage sub-items dynamically based on permissions (tab order must match Ausruestungsanfrage.tsx)
-    const ausruestungSubItems: SubItem[] = [];
-    let ausruestungTabIdx = 0;
-    if (hasPermission('ausruestungsanfrage:create_request')) { ausruestungSubItems.push({ text: 'Meine Anfragen', path: `/ausruestungsanfrage?tab=${ausruestungTabIdx}` }); ausruestungTabIdx++; }
-    if (hasPermission('ausruestungsanfrage:approve')) { ausruestungSubItems.push({ text: 'Alle Anfragen', path: `/ausruestungsanfrage?tab=${ausruestungTabIdx}` }); ausruestungTabIdx++; }
-    if (hasPermission('ausruestungsanfrage:view')) { ausruestungSubItems.push({ text: 'Katalog', path: `/ausruestungsanfrage?tab=${ausruestungTabIdx}` }); ausruestungTabIdx++; }
-
-    // Build Issues sub-items dynamically (tab order must match Issues.tsx)
-    const issuesSubItems: SubItem[] = [
-      { text: 'Meine Issues', path: '/issues?tab=0' },
-      { text: 'Zugewiesene', path: '/issues?tab=1' },
-    ];
-    if (hasPermission('issues:view_all')) {
-      issuesSubItems.push({ text: 'Alle Issues', path: '/issues?tab=2' });
-    }
-    if (hasPermission('issues:edit_settings')) {
-      issuesSubItems.push({ text: 'Einstellungen', path: `/issues?tab=${issuesSubItems.length}` });
-    }
-
-    // Build Checklisten sub-items dynamically (tab order must match Checklisten.tsx)
-    const checklistenSubItems: SubItem[] = [
-      { text: 'Übersicht', path: '/checklisten?tab=0' },
-    ];
-    if (hasPermission('checklisten:manage_templates')) {
-      checklistenSubItems.push({ text: 'Vorlagen', path: '/checklisten?tab=1' });
-    }
-    checklistenSubItems.push({ text: 'Historie', path: `/checklisten?tab=${checklistenSubItems.length}` });
-
     const items = baseNavigationItems
       .map((item) => {
-        if (item.path === '/fahrzeuge') return fahrzeugeItem;
-        if (item.path === '/ausruestung') {
-          const ausruestungSubs: SubItem[] = [
-            { text: 'Übersicht', path: '/ausruestung?tab=0' },
-          ];
-          if (hasPermission('ausruestung:manage_types')) {
-            ausruestungSubs.push({ text: 'Einstellungen', path: '/ausruestung?tab=1' });
-          }
-          return ausruestungSubs.length > 0 ? { ...item, subItems: ausruestungSubs } : item;
-        }
+        // Ausrüstungsanfrage is visible if user has any of the three relevant permissions
         if (item.path === '/ausruestungsanfrage') {
-          const canSeeAusruestung =
+          const canSee =
             hasPermission('ausruestungsanfrage:view') ||
             hasPermission('ausruestungsanfrage:create_request') ||
             hasPermission('ausruestungsanfrage:approve');
-          return { ...item, subItems: ausruestungSubItems, permission: canSeeAusruestung ? undefined : 'ausruestungsanfrage:view' };
+          return { ...item, permission: canSee ? undefined : 'ausruestungsanfrage:view' };
         }
-        if (item.path === '/issues') return { ...item, subItems: issuesSubItems };
-        if (item.path === '/checklisten') return { ...item, subItems: checklistenSubItems };
         return item;
       })
       .filter((item) => !item.permission || hasPermission(item.permission));
 
-    // Apply custom menu order: items in menuOrder are sorted to their index; rest keep relative order
+    // Apply custom menu order
     if (menuOrder.length > 0) {
       items.sort((a, b) => {
         const aIdx = menuOrder.indexOf(a.path);
@@ -299,20 +195,7 @@ function Sidebar({ mobileOpen, onMobileClose }: SidebarProps) {
     }
 
     return hasPermission('admin:view') ? [...items, adminItem, adminSettingsItem] : items;
-  }, [vehicleSubItems, hasPermission, menuOrder]);
-
-  // Expand state for items with sub-items — auto-expand when route matches
-  const [expandedItems, setExpandedItems] = useState<Record<string, boolean>>({});
-
-  const isExpanded = (item: NavigationItem) => {
-    if (expandedItems[item.path] !== undefined) return expandedItems[item.path];
-    // Auto-expand when the current route matches
-    return location.pathname === item.path || location.pathname.startsWith(item.path + '/');
-  };
-
-  const toggleExpand = (path: string) => {
-    setExpandedItems((prev) => ({ ...prev, [path]: !isExpanded({ path } as NavigationItem) }));
-  };
+  }, [hasPermission, menuOrder]);
 
   const handleNavigation = (path: string) => {
     navigate(path);
@@ -330,98 +213,50 @@ function Sidebar({ mobileOpen, onMobileClose }: SidebarProps) {
       <List sx={{ flex: 1 }}>
         {navigationItems.map((item) => {
           const isActive = location.pathname === item.path;
-          const hasSubItems = item.subItems && item.subItems.length > 0;
-          const expanded = hasSubItems && isExpanded(item);
           return (
-            <Box key={item.text}>
-              <ListItem disablePadding>
-                <Tooltip
-                  title={item.text}
-                  placement="right"
-                  arrow
-                  disableHoverListener={!sidebarCollapsed}
-                >
-                  <ListItemButton
-                    selected={isActive}
-                    onClick={() => handleNavigation(item.path)}
-                    aria-label={`Zu ${item.text} navigieren`}
-                    sx={{
-                      justifyContent: sidebarCollapsed ? 'center' : 'initial',
-                      '&.Mui-selected': {
-                        backgroundColor: 'primary.light',
-                        color: 'primary.contrastText',
-                        '&:hover': {
-                          backgroundColor: 'primary.main',
-                        },
-                        '& .MuiListItemIcon-root': {
-                          color: 'primary.contrastText',
-                        },
+            <ListItem key={item.text} disablePadding>
+              <Tooltip
+                title={item.text}
+                placement="right"
+                arrow
+                disableHoverListener={!sidebarCollapsed}
+              >
+                <ListItemButton
+                  selected={isActive}
+                  onClick={() => handleNavigation(item.path)}
+                  aria-label={`Zu ${item.text} navigieren`}
+                  sx={{
+                    justifyContent: sidebarCollapsed ? 'center' : 'initial',
+                    '&.Mui-selected': {
+                      backgroundColor: 'primary.light',
+                      color: 'primary.contrastText',
+                      '&:hover': {
+                        backgroundColor: 'primary.main',
                       },
+                      '& .MuiListItemIcon-root': {
+                        color: 'primary.contrastText',
+                      },
+                    },
+                  }}
+                >
+                  <ListItemIcon
+                    sx={{
+                      color: isActive ? 'inherit' : 'text.secondary',
+                      minWidth: sidebarCollapsed ? 0 : undefined,
+                      justifyContent: 'center',
                     }}
                   >
-                    <ListItemIcon
-                      sx={{
-                        color: isActive ? 'inherit' : 'text.secondary',
-                        minWidth: sidebarCollapsed ? 0 : undefined,
-                        justifyContent: 'center',
-                      }}
-                    >
-                      {item.icon}
-                    </ListItemIcon>
-                    <ListItemText
-                      primary={item.text}
-                      sx={{
-                        display: sidebarCollapsed ? 'none' : 'block',
-                      }}
-                    />
-                    {hasSubItems && !sidebarCollapsed && (
-                      <IconButton
-                        size="small"
-                        onClick={(e) => {
-                          e.stopPropagation();
-                          toggleExpand(item.path);
-                        }}
-                        sx={{ color: isActive ? 'inherit' : 'text.secondary' }}
-                      >
-                        {expanded ? <ExpandLess fontSize="small" /> : <ExpandMore fontSize="small" />}
-                      </IconButton>
-                    )}
-                  </ListItemButton>
-                </Tooltip>
-              </ListItem>
-              {hasSubItems && !sidebarCollapsed && (
-                <Collapse in={expanded} timeout="auto" unmountOnExit>
-                  <List disablePadding>
-                    {item.subItems!.map((sub) => {
-                      const isSubActive = location.pathname + location.search === sub.path;
-                      return (
-                        <ListItemButton
-                          key={sub.path}
-                          onClick={() => handleNavigation(sub.path)}
-                          selected={isSubActive}
-                          sx={{
-                            pl: 4,
-                            py: 0.5,
-                            '&.Mui-selected': {
-                              backgroundColor: 'primary.light',
-                              color: 'primary.contrastText',
-                              '&:hover': {
-                                backgroundColor: 'primary.main',
-                              },
-                            },
-                          }}
-                        >
-                          <ListItemText
-                            primary={sub.text}
-                            primaryTypographyProps={{ variant: 'body2' }}
-                          />
-                        </ListItemButton>
-                      );
-                    })}
-                  </List>
-                </Collapse>
-              )}
-            </Box>
+                    {item.icon}
+                  </ListItemIcon>
+                  <ListItemText
+                    primary={item.text}
+                    sx={{
+                      display: sidebarCollapsed ? 'none' : 'block',
+                    }}
+                  />
+                </ListItemButton>
+              </Tooltip>
+            </ListItem>
           );
         })}
       </List>