yes a big surface backer plate is a must . you have No load on it now add tires engine and van weight will make things move were you think there ok now . if you have to do some fast working on the streering wheel that can add alot of TQ to the mix. one of the joint companys i used borg they worked it out to show how much shear someone can generate with a stander size streering wheel in there hand it was a eye opener