x3, you need a "Spindle Nut Conversion Kit" from any of the hub manufacturers. WARN makes it,
"WARN 29918 Spindle Nut Kit" - this is for all IFS 1986 to 1989. Thats for Automatic Locking Hubs, which is not ADD. ADD came on the 2nd gen runners.
Here is a great explanation and how-to:
Replacing Toyota AUTO Hubs - ORN
You can get the spindle nut conversion kit wherever it is cheapest (they are all the same, you are buying a few washers and nuts). I know WARN makes them, and so does Mile Marker.
The kits are all the same and will work interchangeably with a Aisin, Warn or Mile Marker manual hub.
So if I get a used set of AISIN hubs for my 87 that has an auto lock, what other parts do I need to make the conversion?
Thanks for any help!!
Just the above mentioned spindle nut conversion kit. You will have it installed before you bolt on whatever manual hub you choose.
Please know, you will also need a 54mm Hex Locknut Socket For Toyota FJ, LN, And RN Models. You can get the socket on Amazon or a parts store.