Cane

it all depends on your fab skills and how much money you want to put into this.

for example i don't trust myself with welding, and there were no explorers with the right gear ratio that had disc brakes at my local junkyard, so I bought a '97 LSD 8.25 instead. was half off day so it set me back a big 60$. bought the necessary kit to swap Liberty KJ disc brakes, and for about 250-300$ I have a "new" axle waiting to be swapped under the jeep.

but if you can weld and you can find a 8.8 that fits your needs, since disc brakes are already an option you'll only have to spend money on the perches kit and you'll have a beefier axle in the end.

So like it was said, late 96 and up chrysler 8.25 is what you want for the stronger shafts.

ElMartillo

Great info. I think the 8.8 swap might be the direction I go. Benfit being disc brakes already on it.

I'm setting this XJ up for more expedition/remote routefinding/camping rather than rock crawling. I want larger diameter tires to increase ground clearance, but I don't want to sacrifice fuel economy or tourque, so that's why I'd like to regear. Also will put in a front e-locker and a rear Detroit Truetrack LSD. All of this to consider with the rear end swap.

Stroked98Xj

Discs and 8.8 belong to '96 and newer Ford's, up until they went to independent rear suspension in '02 or something like that. When you are axle hunting, there might be a tag on the diff cover that says "3L73 8 8" or 3 55 8 8" or "4 10 8 8". The first set of numbers means 3.73, or 3.55, or 4.10, in my examples. In the first example where it says "3L73 8 8" means 3.73 gears, 8.8 ring gear, and the L stands for limited slip rear end. No "L" means it's an open diff. If you are planning to put in a new limited slip or locker, then it doesn't matter if the diff has it's own limited slip or not. The limited slip in the Ford 8.8 is the "Trac-Lok" clutch type limited slip, meaning it uses clutches to apply pressure to the wheel that's about to slip in order for it to not slip a little longer. Ultimately, if you're crawling over a stump or backing up over a large rock, it'll likely slip, unless you rebuild the unit. The clutch packs don't really last much longer than 50k miles. If it were me, I'd go for any Ford 8.8 with the gear ratio you intend, then swap in any gear style limited slip or selectable locker. Since you mentioned this is more of an expedition, remote route finding vehicle for camping, this usually means you'll be loaded down with gear and food, right? All this excess weight will move easier with 4.10 gears, so that is what I would focus on searching for in a Ford 8.8, and then re-gear your front axle to match. Again, personally in your case, I would leave the front axle open, and put that money towards a good winch bumper and 9000lb winch. That way you can move trees, climb up soft or slippery inclines, and rescue friends rather than have all 4 wheels turning.

Car-part.com is a good website for searching for this 8.8. I'd start by entering '97 Ford Explorer, search for the rear axle assembly, then narrow your search for 4.10 axles. When you get to the junk yard, make sure you get the drive shaft flange that bolts to the pinion yoke. You will also need 4 bolts, see part number in attached image.

ElMartillo

More great info. Thanks! I'll start looking.

Will I need to install a different proportioning valve for the brakes to work correctly with the 8.8 discs? Does the shock perch mod require a different length shock?

BTW, I already have a front winch bumper and am in the middle of a Warn winch install, so I have that covered. I'm getting this rig dialed in pretty well. Bumpers, suspension and rooftop cargo management completed. After these drivetrain upgrades and a rear cargo storage platform build, the selectable front locker will be one of the last planned mods.

investinwaffles

My 8.8 swap was more involved than an 8.25 swap, and thus cost more money. Used the Iron Rock bracket kit IIRC
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But I gained disc brakes in the rear, 31 spline axles, higher shock mounts, and a limited slip which I rebuilt with carbon fiber clutches when it was geared to 4.88's

​​​​​I also needed to install a SYE, because of the pinion angle.

You will want a ZJ brake proportioning valve and need a rear brake line (Ford is different than Jeep) and custom made parking brake cables. Check East Coast Gear Supply for those parts

Also will probably need a custom Driveshaft or a 1330-1310 conversion ujoint which is what I used with a WJ jeep double car dang front driveshaft.
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Lots of swap guides online, just Google and you will find several step by step guides and probably a YouTube video or two

Edit:
I went with a limited slip carrier because I couldn't afford an air/e-locker and didn't want an auto locker for drivability issues (with a manual trans).
If you want a rear locker, make sure you get an open carrier

Big David

You don't need custom made e brake cables. I got mine for $24 each. They are just for '96 down XJ with rear discs.
So, I guess they are kinda custom.

jbennett

I went with the 8.8, main reasons were to get disc brakes and 4.10 gears with LS. Factoring in the savings on not having to swap gears, I went all out and rebuilt it and went ahead and trussed it as I basically got it free with one of the sales Iron Rock was having.

Don't know if it's been mentioned, but the 8.8 is also about 1-1/4" narrower if that matters to you.

investinwaffles

Didn't you need to cut off the ends to loop them around the parking brake levers in the backing plates? I'm not that familiar with 96 and older XJ's
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ElMartillo

I already have an SYE installed with a Tom Woods driveshaft. Is a different length driveshaft required with the 8.8?

jbennett

You just need this flange yoke to adapt the stock driveshaft.

Spicer # 2-2-1379

Big David

You do that if want to reuse your stock cables. The ones specifically made for '96 & down with added rear discs are bolt on.
I got mine from Morris 4x4 as they were the cheapest, at the time. That was almost 2 years ago.

ElMartillo

After doing some research I'm leaning back toward a 29 spline 8.25 for a few reasons: Less modification necessary just to get it it fit. I just don't have the time. I can regear at a later date. I probably won't get a new wheel/tire setup until the spring, so I can drive it in the meantime. For my uses, the 29 spline 8.25 will do just fine, and is a big upgrade from my existing D35.

Thanks for all the great info here guys!

andrewmp6

And if you do the yukon ultimate 88 it will widen the 8.8 to about the xjs stock width.The kit removes the c clips and upgraded axles and is dual lug patterns 5x4.5 and the 5x5.5.