New here, have a question,

[littlecobra95]

have a question, have a 1994 Ranger Splash 4.0 with mustang 5.0 and AOD. have the orig 8.8 rear end 308 open carrier. how did I find out if it is a 28 or 31 spline axle. second I have a Ford posi unit and need to find out if it 28 or 31. numbers on the gear is 373 E47W AA I4 70A. on the carried is H28 AND F07W - BA.

 

[Curious Hound]

If the trackloc (posi) is not installed, just counthe splines inside one of the holes where the axle shaft goes. It will either be 28 or 31, easy.

On your axle, check out the articles Here Concerning the 7.5” and 8.8” axles to be sure of what you have and how to identify it by codes and inspection. The 8.8” has a larger diameter axle tube that necks down right behind the flange at the end. I don’t remeber at the moment how to identify it as 31 spline other than opening it up and counting splines on an axle or in a side gear. If your axle tag or door sticker are intact, the codes there should help when you check the articles I linked above.

 

[Dirtman]

94 rangers did not have 31 spline 8.8's. It's a 7.5 or 8.8 28 spline.

 

[RonD]

Welcome to TRS

Axle tag should have 3"L"73 on it if it is Limited Slip(posi)
No L = OPEN

As said all Rangers used 28-spline axles in all years, 7.5" or 8.8"
Exception was Ranger FX4 Level II with Torsen differential(2003-2009) it used 31-spline, as did Explorer rear axles

 

[Curious Hound]

94 rangers did not have 31 spline 8.8's. It's a 7.5 or 8.8 28 spline.

I figured a previous owner may have done a swap when the 5.0l was installed. Thats why I pointed him to the tech section so he can figure out what’s really under there.

 

[Dirtman]

True, im just going by the fact that he said "original". Plus if its a 3.08, that was never put in a 31 spline ranger/epxlorer axle. They only used that ratio in the el-cheapo manual transmission 2wd trucks.

 

[Curious Hound]

True, im just going by the fact that he said "original". Plus if its a 3.08, that was never put in a 31 spline ranger/epxlorer axle. They only used that ratio in the el-cheapo manual transmission 2wd trucks.

He may have a mishmash of parts and no updated labels. It might come down to opening the differential and measuring and counting. Original truck might have bern b4000 with 7.5” and 3.08 gears. He might now have a b5000 with 8.8” and 4.10 gears. It could even be LS already and he doesn’t know it. But we’re guessing.