Rear Axle: Studebaker Pickup Rear Axle Ratios

[Frank54]

What rear axle ratios were available for 2R — 8E 1/2-ton trucks? Is there an online guide somewhere? Thanks!

[r1lark]

The Shop Manuals will give you that information, but not sure if you can find them online. There are a number of different ratios depending on the engine size, transmission (3, 4, or 5 speed), overdrive versus standard trans, and tire size.

[StudeRich]

No "Guide" per se' exists for a detail like that, but the Studebaker Parts Catalog does tell what was available.

All the 2R's and the later "169" Flathead '54-60, or "245" Sixes Late '48-'60 because of their fairly low HP and Torque ratings would HAVE to have quite Low (High Numerically) Gears.

Because of their anticipated Hauling and Farm use, they only got slightly Higher geared after that.
Sixes are most commonly 4.56 or 4.88, V8's 4.09 or 4.27, no 3 to one ratios would be Standard.

Truck Axles and Housings are wider than Car axles of the same Type on 1/2 Ton versions, with Dana Model 44's.
All usable Ratios however, are available in aftermarket replacement Ring and Pinion Gear Sets for Model 44's.

Of course there ARE "catches" to all things modern, namely the Spline count is sometimes a problem to match without replacing other Parts.

[StudeRich]

A Very few later Champs do exist with Automatic Trans. and 3.73 Ratio Axles, but VERY Rare.
I like to recommend things that are actually Common, Available and "out there" somewhere..

[PackardV8]

These are the ones in my Truck Specifications Book:
3.73
4.09
4.27
4.56
4.88
Since the 1/2-ton was available with the Champion six, Commander six, the 224", 259" and 289" V8s, six different transmissions and then there were the special orders, anything could be anywhere.

jack vines

[PackardV8]

One thing I just noticed, the 3.90 gear, standard in the '56J overdrive, was not available in my 8E Truck Specification Book

On a close reading, it appears the 8E7 V8 automatics, straight 3-speeds, 4-speed and the 5-speeds could be had with the 3.73 ratio.

jack vines

[StudeRich]

The 3.92 Ratio was dropped after 1958 for all practical purposes, & as "Standard" and Very rare after 1956.

Extra "Special" Orders are out of the realm of "Normal" for most all Cars.

[Frank54]

Thanks for all responses. This is for my general knowledge.

[PackardV8]

StudeRich commented The 3.92 Ratio was dropped after 1958 for all practical purposes, & as "Standard" and Very rare after 1956.

Very interesting, Rich. I just noticed it was missing from the '64 book, but wasn't aware it had been phased out earlier. Come to think of it, the '56J was one of the few standard applications of which I'm aware.

FWIW, I've never seen an OEM Dana 60 with a 3.90 gearset. There are aftermarket 3.90s, but never seen one in a factory truck or car.

jack vines

[enjenjo]

The Dana 44 ratios available are from 3.07 to 5.89. As mentioned other parts may need to be changed to make them work in a Studebaker. Things to watch out for are reverse rotation gears meant for High pinion 4x4 front axles, and there are some oddball gears with larger ring gear bolts.

[PackardV8]

The Dana 44 ratios available are from 3.07 to 5.89. As mentioned other parts may need to be changed to make them work in a Studebaker. Things to watch out for are reverse rotation gears meant for High pinion 4x4 front axles, and there are some oddball gears with larger ring gear bolts.

FWIW, I've seen Dana 44s from as high as 2.56 to as low as 6.33.

jack ivnes

[PackardV8]

FWIW, I've seen Dana 44s from as high as 2.56 to as low as 6.33.

jack vines

I just found a more comprehensive list and there were as high as 2.35 and as low as 7.17, with several unusual ratios I've never seen.

https://media.spicerparts.com/cfs/files/media/YgMnbiCGaHJGjpZoX/XGI.pdf?store=original