Bassaholic

So I have a turdyfive rear axle. I'm running 33's, I don't plan on going bigger than 33's. My plan is to install an 8.25 with 31spline axles, ARB locker, 4.56 gears. I know they came stock with 27 or 29 spline shafts, My question is : since I'm replacing the guts anyway, does it matter if I start with a 27 or 29? Is everything that I would "retain" going to be the same on a 27 vs a 29? 27's are cheaper and easier to find.

Xj88

Why not just buy an 8.8 and have the extra splines from the get go.
Then use a full case locker and you'd be just fine on 33s.

8.8 can be had for like 150 at a pull a part..and some have discs

Lowrange2

Whoa, you're going to have 1500 bucks in a 8.25 when you could have 400 bucks in an 8.8.

Don't do it!

Xj88

This.
For all that you could have a built 44, or 60 lol

4wdparakeet

Run the 29spl stock. I run mine with 35's, and a 4.6l stroker motor and have never broken anything. They are plenty strong for 33's


Parakeet

muffinman

Where do you get an ARB,4.56 gears and the complete 8.8 with xj mounts for 400.00?

94XjSport94

Where are there 31 spline 8.25 shafts and carriers?

muffinman

I have never seen such an animal. Lots of questions in this thread,LOL

Matteo_96xj

If you're replacing a 35, I wouldn't bother with an 8.25 unless it was free or really, really cheap. 8.8's can be had for cheap, or even a D44 out of a late 80's XJ, but those are getting harder to find. Both are a better axle.

Having said that, I'm running an 8.25 in my XJ. It came with it so I left it in. When I bought my Detroit locker I got the 29 spline version and Yukon shafts to match, upgrading from the 27 splines that were in it. It's plenty strong for 33's.

Dan91

So, just curious: does anyone know hub center to bottom of diff measurement for an 8.8? I'm thinking about an 8.8 but I have an 8.25" that I already shaved up a half inch. Any idea what the clearance difference would be?

xjheep92

If u already have the 8.25 I would use it but that's just me

Xj88

I wouldn't waste all that $ on an 8.25. Its a plenty strong axle...but if your gonna dump 1k+ just to get it to be as strong as an 8.8 which can be had for under 200...

Hell, look on craigslist for explorer part outs.
I found a 410 LSD 8.8 for 150 a while back...
31 spline with discs.

Toss a truss on it to put the shock tabs and perches on the right spot and wheel..

Bassaholic

Wow..alot of different opinions on this. Is it believed by most that 33" tires have no chance of breaking a 29 spline 8.25?

Atmos

shaved 8.25 sounds kinda sweet. I'd probably keep that my 8.8 is a big old axle. but I havent found a rock I couldnt bump it over to date. you'll hang up your front axle just as much as your rear if you're in some really good rock sections anyway

I'd be fine running 35's on a 29 8.25. I've always said that once you get into the spline upgrade territory, it's just time for a bigger axle. an 8.25 with alloys, a truss, and heavy diff cover will work wonders. you dont even need all that for 33's

Bassaholic

Also, I am new at owning an XJ, but I have been reading a little about them for a year or so. After reading for a few months I was convinced I wanted a ford 8.8 in the rear of my XJ. But I kept reading and found that for a guy like me, who has never welded and has never been a mechanic, the 8.8 conversion can be quite expensive. I know theres people that claim how cheap it is but I read a post of a guy that kept track of everything it cost and I want to say it was well over a grand maybe closer to $1500.00. In SoCal I think the going rate for an 8.8 with disc brakes is around 450.00. atleast it was when I was looking over a year ago.