You might have encountered this error “Error during serialization or deserialization using the JSON JavaScriptSerializer. The length of the string exceeds the value set on the maxJsonLength property.” when pushing a large data to Telerik’s MVC Grid.
here is a good post how to resolve it.
http://anyrest.wordpress.com/2011/09/27/large-json-result-for-teleriks-mvc-grid/#comment-896