as that will make a little noise if it's too loose. Also, did you use a solid spacer as opposed to the crush sleeve type? That can crush too far upon hard launches, changing the pinion depth, and ruining your gears. Whoever set it up ought to know this if they are familiar with a 9". I run the second design Locker made by Detroit Automotive Products in my 67 Shelby, which has hold out rings that the 65-6 didnt have, and its quieter tham the early ones. There will always be some noise due to the cam action of a ratchet design. The solid spacer was stock on the Nodular case with the "Daytona" support. You can ID it by looking at the retainer bolt surfaces, as they will have been turned on a lathe, instead of cast bosses that the std types have. Look at "Randy's Ring and Pinion" site to see all the different pictures, and an excellent tutorial of the all the different rears.