I am currently having an axle (8.8) set up with 4.88's. I bought it because i was under the impression it was a 31 spline fx4 axle. My Mechanic just finished setting up the gears and told me the locker I bought and the carrier won't fit. This is because it is actually a 28 spline axle. Is there any way I can upgrade and put 31 spline shafts in it? I can't buy a new axle cause he has already spent the time setting up the gears. Help would be awesome.

 

Nope, it won't work.

 

You'll need a complete 31 spline axle, explorer or lvl 2 ranger

 

Are the shafts too big? So no one makes an upgrade kit? Can I have someone make the shaft bigger? I hate to sell my locker, carrier and get new ones.

 

There is no way to make it work, you need a whole nother axle.

 

There are a few main differences between the 28 and 31 spline 8.8.

The axle tubes and shafts are larger. And the diff housing axle tube holes are bigger as a result.

The ring and pinions are interchangeable and so are some lockers. I believe the entire carrier is interchangeable.

Besides the gears and maybe the carrier they are in no way compatible.

^^^^^^ IGNORE THIS PART ^^^^^^


31-spline 8.8s are only on Explorers, Full sizes, and FX4 Level II Rangers. FX4 Off road Rangers are still 28 spline.

 

The carrier isn't interchangable. Thats where the splines are, so the count obviously would be wrong.

 

crap ok thanks guys.

 

there are a few other differences, i suggest looking on TRS at there indepth looks at both. as for the axles, carriers, and ring and pinion do not interchange...

 

Crap. I did a ton of looking before I posted that. I am tarded.

I could have swore that the ring and pinions were good to change out.

Well poop.

 

The 31 spline and 28 spline 8.8 do use the same ring and pinion...

 

I am am trying to get the salvage yard to send me a different rear end because they told me when I bought it that it was from a level II, so hopefully something works out. Thanks everybody.

 

Yes, the ring and pinion does interchange. They are both 8.8's.

 

Do you really need a 31 spline with your 3.0 and 33's?

 

Where did you get the rear end from? I ask because you said you had it SENT to you. I know there was a local yard here that kept trying to sell a Ranger rear end online out of an 04 FX4 as a Level II rear end. I went in and did all the checks and told them it wasn't a Level II. They said ok and continue to advertise it that way. Its a long shot but just checking.

 

Nine years later I'm revisiting this thread.... YES you can put 31 spline axles in a Ranger 8.8 that was originally equipped with 28 spline axles. To much MISinformation in here. No, factory 31 splines axles from an Explorer or very late Ranger won't work but (BETTER) aftermarket axles are available from Strange and Moser, possibly Yukon as well. Guys saying that it won't work are obviously confused. 79-04 Mustang 8.8's and 7.5's are factory equipped with 28 splines and use the SAME axle shaft bearing as a Ranger, be it 7.5 or 8.8... 31 spline axles are swapped into Mustang's extremely often. Those who say 31 spline axles won't fit need to do more research and stop spreading BS....

 

I'm going through this right now on my thread bad vibes. Had Moser make me some 31 spline shafts that are in the mail now. I also have a 31 spline truetrac being delivered today. Moser and my diff guy both say it will work. We will find out!

 

With custom made parts, anything is possible.

But like you said, with your custom made axles, you're still running the same small bearing that comes in the 7.5 rear end.

 

If you're not rock crawling or pumping 500+hp I dont think those bearings will cause you any problems.

 

Then why go to the trouble and expense of having custom made axles ?

 

It ended up costing me the same as replacements from shmoeriely's that are made of cheese, at least in California. Why not? Just takes a bit longer.

Edit: I also got screw in wheel studs so when the tire drone's inevitably cross thread one of my studs I dont need a new axle.