8.8 Axle ID

[Old Sparky]

Hey you gear heads;
I've got a 2010 XLT 4WD, payload package 2.
I'm thinking about putting a Detroit in the 8.8 soon.
I read on some Jeep 8.8 swap site that a 28 spline has 2.75".OD tubes and a 31 spline has 3.25" tubes and necks down at the brakes.
I just went and measured the tube OD; it's 3.25" and necks down at the disc brakes and at the pumpkin.
I'm wondering if Ford just started using Explorer axles when they switched the Ranger to rear disc in '10?
I'm really hoping I have 31 spline axles.

 

[4x4junkie]

I've been told the '10 & '11 axles with the double-necked tubes are 28 spline, though I have yet to actually pull a shaft on one to verify. They are definitely not the same axle from the Explorer though (Ex axles do not neck down at the pumpkin).

 

[Old Sparky]

Aw man! Got my hopes up!
I'm about to change the fluids in the axles/tranny/Tcase, and it's been a long time since I had my Mustang 8.8 apart, so I don't remember - can you count the splines without taking out the crosspin?
And can anyone recommend a good diff cover?

 

[cdawall]

Still has 28 spline shafts in it.

 

[legoms013]

I HIGHLY recommend the Ruff Stuff Cover, with recessed bolts and fill/drain plugs additional options. Kinda pricey but a nuclear bomb proof cover; it is totally worth every penny I paid for mine.

Ol Sparky, do you know if your 8.8 is a trak lok or not? If it is an open diff, it is not that hard to take it a part a little further to slide one or both shafts out. Then you could make a visual confirmation on spline count. If it is a trak lok, it is a bit of a bear to get that damn spring out...

 

[cdawall]

I have no issues from my SOLID covers. Only $65 comes with a tube of silicone. Smashed my pair on many rocks and so far so good.

 

[Old Sparky]

It's an open diff - I tried to get a track slop when I ordered it, but Ford said "no dice" in 2010. Anybody ever get the idea that accountants run Ford? Seems like they're always offering the customer almost what they want.
Anyways, the truck only has 15K on it, so I think the extent of my warranty voiding in the very near future will be changing to synthetic fluids and a diff cover. Thanx for the recommendations.
Now can anybody recommend good synthetic *readily available* 80-90W, manual tranny and T-case fluid?