8.8 28 spline or 31 spline axles
 

Hi Guys,
This is my first post. I been sitting back reading the mail.
The pinion bearing and spider gears are going bad in my 04 4.0 Ranger(175K). The rear axle is a 8.8 w/4:10 trac-loc. I have a 8.8 from a 00(369K) Ranger w/4:10 trac-loc that I dis-assembled and found 28 spline axles. I was about to order spider gears for my my 04 but know I don't know if it has 28 or 31 spline axles. Is there a was to identify what axle spline I have without dis-assembling the rear in the 04? Thanks

Unless it's an fx4 it's got 28 spline.

It is a FX4, so I going to assume it has 31spline axles and order my parts.


Thanks for the quick reply.

Since it's an FX4 it should be 31 spline but I'd measure the axle tubes just to be sure. 31 spline is 3.25" and 28 spline is 3".

That's what I was looking for. A way to accurately determine what spline axles I have. Measuring the axle tubes is a simple and easy means to accomplish this. Thanks again!!!

Aren't the axle tubes the same size? The just neck down to 3" for the bearing on the 28spline. I have a 28spline and when my spiders went I couldn't find replacements anywhere. Ended up buying a LSD mustang carrier on eBay to steal parts off.

I haven't measured the axle tubes yet, will do that tomorrow, but even if they neck down to 3" at the bearings that will tell me they're 28 or 31 spline. I've found 2 places that sell spiders for 28 spline trac-loc. The first is America muscle and the other is Randy's gears. Thanks for the replies.

04 fx4 is a 28 spline

04 fx4 Level II is a 31 spline

you should have a 28 spline if you don't have a Level II

8.8 28 spline or 31 spline axles
 

^^^X2.

But a 31 spline ranger axle tapers down right before the drum from I believe 3.25" to 3". 28 spline is the same measurement all the way. There used to be a picture of it but it's too late to search for it.

I just measured my 28 spline and the tube is 3".

I ordered my parts today they should be here Tues. or Wed.


I measured the 2 diffs. I have and both are identical. The axle tube when it comes out of the center section is 3" after passing the shock mount but before the spring perch the axle tube tapers down to 2.75" and maintains that measurement until it meets the backing plate. If you stand back and look at it or run your hand along the tube the transition is noticeable. Hope this helps somebody. Thanks for the replies.

My parts arrived Tues. Happy days, until I opened the box labeled Ford limited slip spider gears and found spiders for a open rear. Called them, was told that's what their listing shows. The guy was a order taker!!!
Called all the usual suspects, no luck, was even told the 28 spline trac-lock is not rebuildable. Finally found them at West Coat Differential. I even had they guy take them out of the package to confirm the were for a posi. Now we wait and see!!!

That sucks. But looks like you have had the same problem I did so far with 28spline spiders. Hopefully west coast knows what they are talking about