how do you remove a rear axle from a 1990 ford f150 I've heard theres a retainer inside the differential i have to remove but then i heard theres 4 bolts on the hub that hold it in I'm so confused I wanna take it out to check the spline count so I know what kind of differential to get I'd appreciate it if someone could just tel me the spline count to save me the hassle of taking it apart its a ford 8.8 3.08 geared open rear end but just an answer as how to take it out would be appreciated too

 

Should be 31.

 

Open dif has a c-clip inside the pumpkin.
Remove the tire, brake drum, and associated brake hardware. Clean everything.
Remove the dif cover, have a 5 qt. pan underneath, to catch the old fluid.
You'll have to turn the wheel until you can access the c-clips. Have an assistant push in on the axel, and remove the clip(s) with a magnet.
Pull out the axel.
Here's an exploded view of what you're looking at.

 

You have to remove the pinion shaft bolt before you can remove the c-clips. Good luck not to break it.

 

I have heard there is a kit available for getting the broken pinion shaft bolt out once its broken.

 

If the dif isn't in too bad a condition, then once you remove the retaining bolt, it should slide out fairly easily.

 

There is a kit which is a set of extractors and drill guides. Depending where the bolt snapped it can really ruin you're day.

 

I think im being a glass half empty guy. The op shouldn't have any problems pulling his diff apart to verify the are 31 splines in there. But. Its good to know if there are problems, there is support for it.

 

As far as I know ford trucks were 31.

 

Thanks guys for all the responses since it is a 3.08 rear end the dealer said and like all you guys said it is 31 spline thanks for all the responses I'm glad y'all know your differentials