Hey all,

The rear differential on my "new to me" 1985 pick up has to be replaced, and i don't really know where to begin. I bough the truck for a daily driver/moderate off-road project vehicle. It has a four inch suspension lift and 32x11.5 tires already. Since I have to replace the axle, I want to go ahead and put a new one in instead of a temporary replacement. My problem is that I'm new to four wheeling, and I don't know what gear ratio to go with, let alone what locking vs welded vs normal differential really mean and do, or who makes quality toyota axles. Any suggestions you have would be very useful to me. Thanks!

Jason

 

I've a bad diff (Gears?) you can just change the gears for a new set or replace the whole third member. You don't have to change your entire axle, at least if you don't have bent it or something like that.

If what you've is a broken R&P I'd regear for running bigger tires if you'll want to run them. You will have to regear the front as well but it's better than having to repair something you're going to swap later...

David

 

It looks like I'll have to stay with the gearing that's already in, which is 4.11. I think that'll work for me, though in reality I don't have a choice right now since I can't replace the front end, too. After looking around online, I figured out that something in the range of 4.10 to 4.27 would be best for a daily driver. Does that sound right?

 

I am not sure what you are refering to in needing a "new one instead of a temporary replacement." You will spend quite a bit of money buying a brand new 3rd member (as blizzard said above you don't need a whole new axle as you have a "drop out 3rd member"). If you are planning on staying with your tire size than stock would be okay (but not perfect) and I would just go to a junk yard or Ebay or similar and find a 3rd member there.
While you are at it you could buy an 86 or 95 complete axle ( preferrably with a V6) and get a wider width (for stability) and bigger drum brakes. There is plenty of articles on here about rear lockers/spools so I won't write on that; but keep in mind to run a spool or most fulltime lockers the gears gotta come out and it would be better to do a gear swap there. In that case if you replace the gears and the carrier than you could rpbaly keep the 3rd member (unless it exploded and caused some real damage).
Overall what I am saying is that look around for old 3rd member and you can find a great deal if you wanna stay unlocked with 32's or if you wanna a locker and maybe bigger tires one day get a lower set of gears and a good locker (detroit soft-locker, ARB) and get them put in and you can probaly keep your third member.

 

Dont know where your located but try car-part.com. As a DD I recomend a 4cyl. 2 pinion 3rd memb. opposed to the V6 4 pinion unit. It's lighter and is the only one that you'll find stock 4:30's and 4:10's, which should work well for your purposes. Cheaper lockers for this one as well. If you can purchase an entire axle assembly be sure to get it off a 4Runner, they have larger brake shoes(than same years trucks) , a nice bonus I discovered when I got mine.