diff --git a/indra/newview/app_settings/settings.xml b/indra/newview/app_settings/settings.xml
index 60e6a89371..667953ab54 100644
--- a/indra/newview/app_settings/settings.xml
+++ b/indra/newview/app_settings/settings.xml
@@ -1830,6 +1830,17 @@
     <key>Value</key>
     <integer>0</integer>
   </map>
+    <key>DebugSelectionLODs</key>
+    <map>
+        <key>Comment</key>
+        <string>Force selection to show specific LOD, -1 for off, 0 - lowest, 4 - high.</string>
+        <key>Persist</key>
+        <integer>0</integer>
+        <key>Type</key>
+        <string>S32</string>
+        <key>Value</key>
+        <integer>-1</integer>
+    </map>
   <key>AnimatedObjectsAllowLeftClick</key>
   <map>
     <key>Comment</key>
diff --git a/indra/newview/llselectmgr.cpp b/indra/newview/llselectmgr.cpp
index 885f4d993e..cbc52aeec6 100644
--- a/indra/newview/llselectmgr.cpp
+++ b/indra/newview/llselectmgr.cpp
@@ -250,6 +250,23 @@ LLSelectMgr::LLSelectMgr()
 
     mForceSelection = FALSE;
     mShowSelection = FALSE;
+
+    LLControlVariable* ctrl = gSavedSettings.getControl("DebugSelectionLODs").get();
+    if (ctrl)
+    {
+        mSlectionLodModChangedConnection = ctrl->getSignal()->connect([this](LLControlVariable*, const LLSD&, const LLSD&)
+        {
+            for (LLObjectSelection::iterator iter = mSelectedObjects->begin();
+                iter != mSelectedObjects->end(); ++iter)
+            {
+                LLViewerObject* object = (*iter)->getObject();
+                if (object)
+                {
+                    object->updateLOD();
+                }
+            }
+        });
+    }
 }
 
 
@@ -259,6 +276,7 @@ LLSelectMgr::LLSelectMgr()
 LLSelectMgr::~LLSelectMgr()
 {
     clearSelections();
+    mSlectionLodModChangedConnection.disconnect();
 }
 
 void LLSelectMgr::clearSelections()
diff --git a/indra/newview/llselectmgr.h b/indra/newview/llselectmgr.h
index 1ce53fe149..e3ecdf1013 100644
--- a/indra/newview/llselectmgr.h
+++ b/indra/newview/llselectmgr.h
@@ -932,6 +932,7 @@ private:
     BOOL                    mForceSelection;
 
     std::vector<LLAnimPauseRequest> mPauseRequests;
+    boost::signals2::connection mSlectionLodModChangedConnection;
 };
 
 // *DEPRECATED: For callbacks or observers, use
diff --git a/indra/newview/llviewermenu.cpp b/indra/newview/llviewermenu.cpp
index ad2675a786..39cd72c6b2 100644
--- a/indra/newview/llviewermenu.cpp
+++ b/indra/newview/llviewermenu.cpp
@@ -5510,6 +5510,38 @@ class LLToolsEnablePathfindingRebakeRegion : public view_listener_t
     }
 };
 
+class LLToolsCheckSelectionLODMode : public view_listener_t
+{
+    bool handleEvent(const LLSD& userdata)
+    {
+        std::string param = userdata.asString();
+        static LLCachedControl<S32> debug_selection_lods(gSavedSettings, "DebugSelectionLODs", 0);
+        if ("default" == param)
+        {
+            return debug_selection_lods() < 0;
+        }
+        else if ("high" == param)
+        {
+            return debug_selection_lods() == 3;
+        }
+        else if ("medium" == param)
+        {
+            return debug_selection_lods() == 2;
+        }
+        else if ("low" == param)
+        {
+            return debug_selection_lods() == 1;
+        }
+        else if ("lowest" == param)
+        {
+            return debug_selection_lods() == 0;
+        }
+
+        return false;
+    }
+};
+
+
 // Round the position of all root objects to the grid
 class LLToolsSnapObjectXY : public view_listener_t
 {
@@ -8319,6 +8351,36 @@ class LLToolsSelectBySurrounding : public view_listener_t
     }
 };
 
+class LLToolsSelectionLODMode : public view_listener_t
+{
+    bool handleEvent(const LLSD& userdata)
+    {
+        std::string param = userdata.asString();
+        if ("default" == param)
+        {
+            gSavedSettings.setS32("DebugSelectionLODs", -1);
+        }
+        else if ("high" == param)
+        {
+            gSavedSettings.setS32("DebugSelectionLODs", 3);
+        }
+        else if ("medium" == param)
+        {
+            gSavedSettings.setS32("DebugSelectionLODs", 2);
+        }
+        else if ("low" == param)
+        {
+            gSavedSettings.setS32("DebugSelectionLODs", 1);
+        }
+        else if ("lowest" == param)
+        {
+            gSavedSettings.setS32("DebugSelectionLODs", 0);
+        }
+
+        return true;
+    }
+};
+
 class LLToolsShowHiddenSelection : public view_listener_t
 {
     bool handleEvent(const LLSD& userdata)
@@ -9563,6 +9625,7 @@ void initialize_menus()
     view_listener_t::addMenu(new LLToolsSelectInvisibleObjects(), "Tools.SelectInvisibleObjects");
     view_listener_t::addMenu(new LLToolsSelectReflectionProbes(), "Tools.SelectReflectionProbes");
     view_listener_t::addMenu(new LLToolsSelectBySurrounding(), "Tools.SelectBySurrounding");
+    view_listener_t::addMenu(new LLToolsSelectionLODMode(), "Tools.SelectionLODMode");
     view_listener_t::addMenu(new LLToolsShowHiddenSelection(), "Tools.ShowHiddenSelection");
     view_listener_t::addMenu(new LLToolsShowSelectionLightRadius(), "Tools.ShowSelectionLightRadius");
     view_listener_t::addMenu(new LLToolsEditLinkedParts(), "Tools.EditLinkedParts");
@@ -9594,6 +9657,7 @@ void initialize_menus()
     view_listener_t::addMenu(new LLToolsEnablePathfindingView(), "Tools.EnablePathfindingView");
     view_listener_t::addMenu(new LLToolsDoPathfindingRebakeRegion(), "Tools.DoPathfindingRebakeRegion");
     view_listener_t::addMenu(new LLToolsEnablePathfindingRebakeRegion(), "Tools.EnablePathfindingRebakeRegion");
+    view_listener_t::addMenu(new LLToolsCheckSelectionLODMode(), "Tools.ToolsCheckSelectionLODMode");
 
     // Help menu
     // most items use the ShowFloater method
diff --git a/indra/newview/llvovolume.cpp b/indra/newview/llvovolume.cpp
index 316e0206d3..b4ea06f8b7 100644
--- a/indra/newview/llvovolume.cpp
+++ b/indra/newview/llvovolume.cpp
@@ -1503,11 +1503,16 @@ BOOL LLVOVolume::calcLOD()
 
     mLODAdjustedDistance = distance;
 
+    static LLCachedControl<S32> debug_selection_lods(gSavedSettings, "DebugSelectionLODs", 0);
     if (isHUDAttachment())
     {
         // HUDs always show at highest detail
         cur_detail = 3;
     }
+    else if (isSelected() && debug_selection_lods() >= 0)
+    {
+        cur_detail = llmin(debug_selection_lods(), 3);
+    }
     else
     {
         cur_detail = computeLODDetail(ll_round(distance, 0.01f), ll_round(radius, 0.01f), lod_factor);
diff --git a/indra/newview/skins/default/xui/en/menu_viewer.xml b/indra/newview/skins/default/xui/en/menu_viewer.xml
index 5b0ebf1110..6e92d91320 100644
--- a/indra/newview/skins/default/xui/en/menu_viewer.xml
+++ b/indra/newview/skins/default/xui/en/menu_viewer.xml
@@ -1598,7 +1598,65 @@ function="World.EnvPreset"
              function="ToggleControl"
              parameter="RenderDisablePostProcessing" />
           </menu_item_check>
-          
+
+
+          <menu
+           create_jump_keys="true"
+           label="Selection level of detail"
+           name="Selection level of detail"
+           tear_off="true">
+
+              <menu_item_check
+                label="Default"
+                name="Default lod setting">
+                  <menu_item_check.on_check
+                   function="Tools.ToolsCheckSelectionLODMode"
+                   parameter="default" />
+                  <menu_item_check.on_click
+                   function="Tools.SelectionLODMode"
+                   parameter="default" />
+              </menu_item_check>
+              <menu_item_check
+                label="High"
+                name="High lod setting">
+                  <menu_item_check.on_check
+                   function="Tools.ToolsCheckSelectionLODMode"
+                   parameter="high" />
+                  <menu_item_check.on_click
+                   function="Tools.SelectionLODMode"
+                   parameter="high" />
+              </menu_item_check>
+              <menu_item_check
+                label="Medium"
+                name="Medium lod setting">
+                  <menu_item_check.on_check
+                   function="Tools.ToolsCheckSelectionLODMode"
+                   parameter="medium" />
+                  <menu_item_check.on_click
+                   function="Tools.SelectionLODMode"
+                   parameter="medium" />
+              </menu_item_check>
+              <menu_item_check
+                label="Low"
+                name="Low lod setting">
+                  <menu_item_check.on_check
+                   function="Tools.ToolsCheckSelectionLODMode"
+                   parameter="low" />
+                  <menu_item_check.on_click
+                   function="Tools.SelectionLODMode"
+                   parameter="low" />
+              </menu_item_check>
+              <menu_item_check
+                label="Lowest"
+                name="Lowest lod setting">
+                  <menu_item_check.on_check
+                   function="Tools.ToolsCheckSelectionLODMode"
+                   parameter="lowest" />
+                  <menu_item_check.on_click
+                   function="Tools.SelectionLODMode"
+                   parameter="lowest" />
+              </menu_item_check>
+          </menu>
         <menu_item_separator/>
 
                 <menu_item_check