Hello, I just bought my first 4runner...an 87 IFS...and am building it for my girlfriend. I am looking for an 85 solid axle for me. I am looking to swap in 4.88 thirds front and rear and there is a guy near where I live parting out a 93 4runner with 4.88 gears but it has the ADD instead of manual lockers. I am wondering if the front will work in mine...mine has manual lockers. Any help would be much appreciated. Thanks

 

Another question...can I just remove my thirds and put it the donor thirds? Or is any modification needed to the housing

 

86-95 IFS fronts are interchangeable
79-95 rear 8" thirds are interchangeable
79-85 front 8" thirds will work in the front or rear

 

So the thirds just come out and the new one goes in? Does not matter that I have a 4cyl housing and am puting v6 thirds in?

 

That is correct, it does not matter whether it is a 4- or 6-cyl 3rd. I threw V6 3rds in my '85 and they fit right in.

 

You will have to swap Side tubes on the front diff.

Since your 87 was not equipped with ADD, you will not have 4wd reliably if you just put in the ADD diff, since you do not have the actuation system.

The hubs make zero difference, but you will need to unbolt the longside tube from your diff, and from the ADD diff, and swap them. They are interchangeable, but make sure you have a good set of torx head sockets before you start.

Other than that, you'll be fine. Once you swap the tube, you will have completely gotten rid of the ADD portion of the diff, and you'll be all set to put it in.

If you do not swap tubes, you can move the collar over so the front diff is engaged, but when the truck is in 2wd, and the front hubs are unlocked, it will be easy for the collar to rattle over into the "unlocked position, and you would have to crawl under, pull off the access cover, and relock the collar everytime you wanted to use 4wd.