diff --git a/doc/go1.8.html b/doc/go1.8.html
index 820a0b287a0..4dc6b79bd64 100644
--- a/doc/go1.8.html
+++ b/doc/go1.8.html
@@ -1320,6 +1320,22 @@ crypto/x509: return error for missing SerialNumber (CL 27238)
         to use IPv4 as a backup if it looks like IPv6 might be
         failing.
       </li>
+
+      <li> <!-- CL 31726 -->
+        The <a href="/pkg/net/http/#Transport"><code>Transport</code></a>
+        no longer reads a byte of a non-nil
+        <a href="/pkg/net/http/#Request.Body"><code>Request.Body</code></a>
+        when the
+        <a href="/pkg/net/http/#Request.ContentLength"><code>Request.ContentLength</code></a>
+        is zero to determine whether the <code>ContentLength</code>
+        is actually zero or just undefined.
+        To explicitly signal that a body has zero length,
+        either set it to <code>nil</code>, or set it to the new value
+        <a href="/pkg/net/http/#NoBody"><code>NoBody</code></a>.
+        The new <code>NoBody</code> value is intended for use by <code>Request</code>
+        constructor functions; it is used by
+        <a href="/pkg/net/http/#NewRequest"><code>NewRequest</code></a>.
+      </li>
     </ul>
 
   </dd>