Gear Ratios and did any trucks use 8.8 31 spline rear ends?

[racprops]

I am searching for info about very low gear ratios in Ford 8.8 31/28 spline rear ends.

This is all I can find on the low 2:26 2:47 ratios:

Ring gear measures 8.8".
28 Spline axle shafts with a 1.29" diameter
31 Spline axle shafts with a 1.32" diameter
Ratios: 2.26, 2.47, 2.73, 3.08, 3.27, 3.31, 3.45, 3.55, 3.73, 4.10 & 4.56, 5.14

learned some more things that MIGHT stop my plans.

There are two axle shafts used:

28 Spline axle shafts with a 1.29" diameter
31 Spline axle shafts with a 1.32" diameter

First I have the 31 Spline rear end.

Second gears from a 28 spline will NOT interchange with 31 Spline rear ends.

Third I cannot find out what gears sets are/were made for which axles.

So now I need to find out what gears were made from what splines.

I am here because of this data:

1986-2017 Ford Mustang
1982-2012 Ford F-150
1982-1996 Ford Bronco
1991-2011 Ford Ranger 4.0L models
1991-2001 Ford Explorer (Solid axle)
1979-2011 Ford Panther platform vehicles[2]

I was told this: "Before overdrive transmissions were common, low final drives were used to help fuel economy. I had a V8 Chevrolet Monza with a 3 speed automatic and a 2.29 final drive. Shouldn't be too hard to find other applications like that."

Thanks for your help.

Rich

[Aerocoupe]

So WTF? Any 8.8 ring gear and pinion set will work in an 8.8 housing. The carrier doesn’t care what the gear ratio is. Wikipedia is not the best source to cite with it comes to information like this. Its a good place to start but probably some of the best info on the 31 spline 8.8 would be:

http://www.explorer4x4.com/

https://www.pirate4x4.com/ (they swap in a lot of 8.8's)

https://www.f150forum.com/

You may be getting confused with 28 and 31 spline axles due to the spider gears in the carrier having to match the axle spline count. It would be rare to see a 31 spline axle 8.8 have sub 3.00 gears as most if not all factory 31 spline axle 8.8’s were in heavy vehicles like Explorers and F150’s with the exception of the '99 and up Cobras but they are IRS. To my knowledge the Rangers had 28 spline.

So if you currently have a 31 spline rear end in working order you just need to order gears, install them, and then have all the fun of setting up the contact pattern so they wear correctly and don't make noise. I pay someone to do this as it’s a pain in the ass.

[gregamorton]

I had a mustang 2 guy years ago tell me he had those 2.26 gears and I told him never heard about them. He had a hot 305 and 5 speed in can and he said cam wS so big it would not pull 4-5th gear. I’m all about the 2.47-2.75 gears in a 9” and buy them when I get a chance.