diff --git a/docs/changelog/7.x.x.txt b/docs/changelog/7.x.x.txt
index 4ad2815d9..4aceef805 100644
--- a/docs/changelog/7.x.x.txt
+++ b/docs/changelog/7.x.x.txt
@@ -2,6 +2,8 @@
  - Prevent Help index from trying to link to non-existant documentation
  - fix: can't see the send private message link
  - fix: delete and become user links are shown for user list after deleting user
+ - fix: Threads and CollabSystem have new way to calculate ratings more
+   accurately
  - fix: Inbox shows Next page link when is empty
  - fix: Change Owner in Security Tab in Assets is not always Working
  - All toolbar icons now have a class called "toolbarIcon" so they can be
diff --git a/docs/upgrades/upgrade_7.4.5-7.4.6.pl b/docs/upgrades/upgrade_7.4.5-7.4.6.pl
index ac4b1db99..8bfaab836 100644
--- a/docs/upgrades/upgrade_7.4.5-7.4.6.pl
+++ b/docs/upgrades/upgrade_7.4.5-7.4.6.pl
@@ -21,6 +21,7 @@ my $quiet; # this line required
 my $session = start(); # this line required
 
 # upgrade functions go here
+recalculateThreadRatings($session);
 
 finish($session); # this line required
 
@@ -32,6 +33,24 @@ finish($session); # this line required
 #	# and here's our code
 #}
 
+#----------------------------------------------------------------------------
+# Have Threads recalculate their own ratings
+sub recalculateThreadRatings {
+    my $session = shift;
+    print "\tRecalculating Thread ratings. This may take a while... " unless ($quiet);
+
+    my $root        = WebGUI::Asset->getRoot($session);
+    my $threadIds
+        = $root->getLineage(["descendants"], {
+            includeOnlyClasses => ["WebGUI::Asset::Post::Thread"]
+        });
+    
+    for my $threadId (@$threadIds) {
+        WebGUI::Asset->newByDynamicClass($session, $threadId)->updateThreadRating;
+    }
+    
+    print "OK!\n" unless $quiet;
+}
 
 
 # ---- DO NOT EDIT BELOW THIS LINE ----
diff --git a/lib/WebGUI/Asset/Post/Thread.pm b/lib/WebGUI/Asset/Post/Thread.pm
index c1bc2de92..50a99636a 100644
--- a/lib/WebGUI/Asset/Post/Thread.pm
+++ b/lib/WebGUI/Asset/Post/Thread.pm
@@ -791,26 +791,28 @@ Update the cumulative ratings in this thread
 =cut
 
 sub updateThreadRating {
-	my $self = shift;
-	my $ratingSumSQL = <<EOSQL;
-select sum(Post.rating) from Post
-	left join assetData on
-		Post.assetId=assetData.assetId
-	left join asset on
-		asset.assetId=assetData.assetId
-		and assetData.revisionDate=(SELECT max(revisionDate) from assetData where assetData.assetId=asset.assetId)
-	where
-		Post.threadId=?
-	
-EOSQL
-	my ($sum) = $self->session->db->quickArray($ratingSumSQL, [$self->getId]);
-	$self->update({threadRating=>$sum});
-	my $parent = $self->getParent;
-	if (defined $parent) {
-		$parent->recalculateRating;
-	} else {
-		$self->session->errorHandler->error("Couldn't get parent for thread ".$self->getId);
-	}
+    my $self        = shift;
+    my $session     = $self->session;
+
+    my $calcRating  = 0; 
+    my $postIds     = $self->getLineage(["descendants","self"], {
+        includeOnlyClasses => ["WebGUI::Asset::Post","WebGUI::Asset::Post::Thread"],
+    });  
+
+    $calcRating += $session->db->quickScalar(
+        "SELECT SUM(rating) FROM Post_rating WHERE assetId IN (".$session->db->quoteAndJoin($postIds).")"
+    );     
+
+    $self->update({
+        threadRating    => $calcRating
+    });  
+
+    my $parent = $self->getParent;
+    if (defined $parent) {
+        $parent->recalculateRating;
+    } else {
+        $self->session->errorHandler->error("Couldn't get parent for thread ".$self->getId);
+    }    
 }
 
 
diff --git a/lib/WebGUI/Asset/Wobject/Collaboration.pm b/lib/WebGUI/Asset/Wobject/Collaboration.pm
index c71bf3f31..68a5d62ad 100644
--- a/lib/WebGUI/Asset/Wobject/Collaboration.pm
+++ b/lib/WebGUI/Asset/Wobject/Collaboration.pm
@@ -1166,14 +1166,34 @@ Calculates the rating of this forum from its threads and stores the new value in
 =cut
 
 sub recalculateRating {
-        my $self = shift;
-        my ($count) = $self->session->db->quickArray("select count(*) from Thread left join asset on Thread.assetId=asset.assetId 
-		left join Post on Thread.assetId=Post.assetId where asset.parentId=?",[$self->getId]);
-        $count = $count || 1;
-        my ($sum) = $self->session->db->quickArray("select sum(Post.rating) from Thread left join asset on Thread.assetId=asset.assetId 
-		left join Post on Thread.assetId=Post.assetId where asset.parentId=?",[$self->getId]);
-        my $average = round($sum/$count);
-        $self->update({rating=>$average});
+    my $self = shift;
+    
+    # Get the number of threads
+    my ($count) 
+        = $self->session->db->quickArray(
+            "select count(*) from Thread 
+                left join asset on Thread.assetId=asset.assetId 
+                left join Post on Thread.assetId=Post.assetId 
+                    AND Thread.revisionDate = (SELECT MAX(revisionDate) FROM Thread t WHERE t.assetId=asset.assetId)
+                where asset.parentId=?",
+            [$self->getId]
+        );  
+    $count = $count || 1;
+    
+    # Get the ratings of all the threads
+    my ($sum) 
+        = $self->session->db->quickArray(
+            "SELECT SUM(Thread.threadRating) 
+                FROM Thread 
+                LEFT JOIN asset ON Thread.assetId=asset.assetId 
+                LEFT JOIN Post ON Thread.assetId=Post.assetId
+                    AND Thread.revisionDate = (SELECT MAX(revisionDate) FROM Thread t WHERE t.assetId=asset.assetId)
+                WHERE asset.parentId=?",
+            [$self->getId]
+        );
+
+    my $average = round($sum/$count);
+    $self->update({rating=>$average});
 }