FOX-GTA_89

Im looking to charge my rear end. is it possible to swap it to some stock differential from an other vehicule, and install ladders bars to it and readdy to go or need minor modification?Or absolutely need stange or mooser etc???

Apeiron

The only thing that will fit that easily is a stock rear end from a 3rd or 4th gen f-body.

FOX-GTA_89

i already know...but still a ****ty 7'5 10 ou 9 bolt...any thing else??
4 gen is to wide!

FOX-GTA_89

in able to do some more modification... welding is not a problem...
just would like a diff the same lenght and same bolt patern to keep the stock look....and a way to have functional brakes. i thought that it would be easy to do a swap if i remove the tork arm and remplace to for ladder bars.

other suggestion...the guy that did a 8,8 ford custom conversion the worst was the tork arm bracket welded to the diff cassing no?

Apeiron

Nothing else will be the right width, you'll need new axles.

FOX-GTA_89

i own 3 differential
-one 9 bolt 3:45 installed on my car posi is not working anymore.
-one 9 bolt 3:45in pieces.
-one 1994 camaro 3:42 10 bolt...

what should i do?

my car will probabely run high 13' and want to run slicks

Apeiron

Fix one of the 9 bolts, or use the 94 10 bolt, put in a solid bearing spacer and a stud girdle and weld the axle tubes.

FOX-GTA_89

if i do those mofifications the diff will be 100% locked???
so will break if use on street?
i want a streetable car... im not sure tu understand your modifications...but thank you for keeping answering

Apeiron

None of those things will lock the rear. If it's an open rear it will still be an open rear, if it's posi it will still be posi.

AlkyIROC

The trick is to finding another diff that's the same width or as close to possible as a third gen. My 9" housing is out of a 1979 F100. The only disadvantage of this housing is that the pinion is centered 2" to the passenger side. This isn't really a problem for me and an advantage is that the axles are the same length so I can swap the axles side to side every now and then. The only thing factory about my 9" is the housing.

Since you plan on using ladder bars, it doesn't matter if the housing you find is from a leaf or coil spring vehicle. Cut off the spring/shock mounts off a third gen diff and weld them onto the new diff.

There are many choices as to what you can swap into a third gen if you're willing to do the modifications for an alternative suspension such as ladder bars. The 9" would be the easiest since there are more of them around than just about any other diff and parts are cheap and plentiful. Next choice would be a car, not truck, 12 bolt but chances of finding one narrow enough is very slim. A first gen 12 bolt will fit but for the price, you might as well buy a new bolt in 12 bolt. Other choices are the Ford 8.8, Dana 60, Dodge 8-3/4. You might even find a GM 8.5" 10 bolt to fit.

83 Crossfire TA

iTrader: (2)

13’s? Even a 10 bolt will hold, but from the list of parts I’d rebuild the posi in the 9 bolt… shim it as tight as you can get it and still reassemble it and run with it, you can go quite a bit past factory rebuild specs and still have a successful rebuild, but at some point you end up having to cut out the end of the cones and or the raised section in the end of the case that the cone sits in to make room.

Streetable? I’ve been running a spool in my formula on the street for 2-3 years now (it’s as close to a consistent daily driver as I own, probably is driven more days then the rest of my cars put together)… I guess streetability is subjective. I like not having to rebuild posies anymore in something that I beat on more then I mind the occasional hopping/chirping.

83 Crossfire TA

iTrader: (2)

swapping axles side to side is a _really_ bad idea, changing the direction that the axle has a heavy load put on it is roughly the same as taking a paperclip and bending it back and forth… it will eventually result in breakage.

If you’re up to doing those things I’m not really sure why you’re asking the question… pick something, whatever you find that looks good or you like or want to spend money on, cut and weld and be done with it.

Mkos1980

iTrader: (8)

My Stock 9 bolt with 90K on it is still holding up to 12 sec passes with a 1.8 60 foot on MT ET Streets.

FOX-GTA_89

witch one is better? should i stay with 9 bolt reshimed?

or install the top shape 10 bolt...I think i will slash my ET DRAG with the fenders...because of the 4 inches wider.

spool for 9 bolt??? how much more abuse it will be able to take??
how much it $$$

83 Crossfire TA

iTrader: (2)

The 9 bolt is stronger, the rumor is that it’s about the same as a dana44.

Spool… well, I cut apart my posi carrier after it got to the point that it was too thin to rebuild, cut up the cones and cut beveled pockets into it and welded it up into a solid piece (yes, I welded my rear, no it’s nowhere near as butch as most welded rears, this thing is actually a nice assembly with the side splines welded to the housing, can still be disassembled…).

How much abuse… well, this time I didn’t break the gears or the posi, I corkscrewed the axles, so basically as much abuse as a 28 spline axle will take. And actually that raises another issue, the 9 bolt doesn’t use c-clips but has bearing retainers at the ends of the axles, making it much safer then a c-clip axle.

FOX-GTA_89

im gonna rebuilt my 9 bolt with shimed posi and when i have no choice im gonna do like you....but you hve any pics?sound like chiniese to me... wantto be able to explain the garage what to do exactly.

thank you so much if i can peel 2 tires again for a long time for less $$$ thats all mathers!!

83 Crossfire TA

iTrader: (2)

Rebuilding the posi: There are pretty good, detailed instructions in the FSM and in the tech section on this site. Look them up, they’re a good start.

I’ll add a quick nutshell description and note where I did things differently/suggestions:

Unbolt the axle retainers, pull the axles, pull the cover, remove the bearing caps (make sure that you remember what side everything came from so you can put it back like it came out), pop the carrier/ring gear assembly out of the housing.

To the rebuild you need some kind of fixture to hold an axle, I took a chunk of wood, cut 2 shoulders to sit on top of my vice jaws, drilled a hole through the middle and then sliced it in half on the table saw to make some clap pads for the job (sorry about the huge pics, but I don’t have time right now to make small ones, upload them…):



Through the whole deal use the axles as alignment tools.

Before you disassemble it check this spot out:



It’s hard to see in that pic, but if the end of the cone is contacting the end of the case your case is worn out of spec and you’ll either have to do some machining to it to make it work or get a new case.

With it sitting on the bottom axle, housing bolts up, unbolt the smaller, center bolts and pull the end of the housing/ring gear off.

When you do that you’ll see this (except you’ll have it in the case side, not the ring gear side like in that pic):



if you lift the spider/cross/preload spring assembly off you’ll get this:



If you lift that side gear out of the end of the case you’ll see the pocket where you put the shims, there will be one on each side between the side gear and the cone in both sides of the case (unfortunately I don’t have a good picture). You can use any shims that are small enough to drop into the machined area between the 2, I usually use 10bolt or ford 8.8” pinion shims. Actually, the last time I think I just stopped by the local machine shop and got a stack of whatever left over shims they had approximately the right diameter.

* This is where I differ from the instructions on the site or in the FSM, forget measuring clearances or anything else, just load both pockets with as much shim as you can get in there and still reassemble the case completely. I’ve never seen one of these get so tight you can’t reassemble it and you’ll be kicking yourself if you do any less and start spinning one wheel again sooner then you had to. The shim packs will probably have to be the same thickness on both sides.

From there the reassembly is the opposite of the disassembly, just make sure that you have both axles installed and fully bottomed before torquing all the bolts, if you don’t line up the splines in the side gears and cones before then it’ll be next to impossible to do with it assembled.

Now if the case is worn out of spec, you can usually get some life out if it still. What happens is that there are some rings machined into the end of the cones and the case to contact if the case is worn down too far, if you cut them down you can get some extra life out of it.

This is what it looks like if the cone and case ends are worn to the point where they’re grinding into each other, case side:



Cone side:



What Ive done before is machine those down till they no longer contact (as a matter of fact, I think I machined them down till I had over .125” clearance). Again, case side:



Cone side:



FWIW, I did the inside of the case on a drill press with a surfacing disk and I did the cone side with an angle grinder by hand, just played with them till I got them within about .005 of flat… If I remember right I ended up cutting close to 1/4 “ total to make sure that everything fit.

Eventually, after a few more rebuilds the cones/case will wear enough that they get too thin, and I started getting cracking around the opening that I mentioned to check above to see if it’s worn past spec. When that happened I pulled it all apart, bevel ground the sides of the cones, centered them up in the housing using the axels and welded them in, like this:

83 Crossfire TA

iTrader: (2)

Alright, it's annoying me, I'm going to resize the pics, hold on, they'll dissappear for a few minutes but they'll be right back

Heh, it's amazing, it looks like I resized them all, uploaded the new ones and changed all the names in my post without screwing any of them up.... I suppose there had to be a first time for it, huh?

AlkyIROC

Try to keep pictures under 600 pixels wide on all posts. Anything larger is just annoying.

3.8TransAM

That is a truly awesome post 83 Crossfire

I'll be doing some of this shortly on the TTA.

Hate having a shoestring budget, but I will make it work

Thanks for the insiteful and documented info

Sure between the manual and the repairs listed here I can make one out of two fully functional lol

later
Jeremy

83 Crossfire TA

iTrader: (2)

Ok, generally I try to resize to fit in 640x480 or 640x640 for forum stuff, since that allows most people to see it even with their browser open in a window rather then full screen and still leaves enough detail to actually see things, and initially I was just trying to get the information up while doing something else…

CrazyHawaiian

Great info, great pics. Thanks.

83 Crossfire TA

iTrader: (2)

I’ve gotten requests for the original pics… I put them back together with some slightly edited text here:
http://mpikas.blogspot.com/2008/03/r...rner-cone.html