Originally Posted by chrischhorn

You CANNOT retain the AT diff. You can use the AT pumpkin/shell but not the actual diff itself. A set of shims is all custom ordered. There is no set shims that magically work. Every thing with the diff is custom fit. Shims can be ordered from .005" to .060" in increments of .005 at $16/pair from Courtesy Nissan and its not likely that you will use the same size on both sides. YOU have to measure the shims and find out which size your need unless you just order them all and figure out which ones you need.... Not only that you still need to measure the pinion depth for backlash. I learned after about 8 hours of shimming that I should let a shop take care of it as this is my first diff but without all the shims at your disposal much less measuring everything to the thousandths of an inch.... Without the proper tools and measuring equipment, there is just no way to install the 4.08 gears and diff properly.