Looking at lockers to my X and I found one . LOCK RIGHThttp://www.truckperformance.com/products/searchtype_56d/sortorder_ADAAA/productcategory_Lockers~Limited+Slip+Differentials/category_Drivetrain+~~+Axle/sf1_NISSAN/sf2_2000/sf3_ Xterra/sf4_Search+By+Vehicle+Applications/

But I am not familar . Are all Xs LSD

Not all X's are LSD. There is an orange sticker on the pumpkin, if it is, and it has not fallen off. Also, the only lockers that I know of are ARB lockers.

I just ordered mine from here.

http://www.4x4parts.com/public_html/shop/index.php3?
They had the best price that I could find and they are very helpful and knowledgeable. I have ordered from them before. ARB's are not cheap, but don't get in the way when you are on the pavement.

They will fit LSD or open diffs.

The one you are thinking of might be for a 31 spline diff....which you don't have if you have an Xterra.



The ARB airlocker might be your only real choice for a full locker right now....unless you are adept at fab work, and can do some mechanical swapping work to adapt your current set to work with 31 spilnes, etc.

And - the LSD diffs have a tag that says "Use LSD Oil" on them too.