Backstory: I stuffed a large IBR four speed into my Valiant assuming it would be an overdrive, on the test drive I pulled the gear lever into what should have been 4th on the freeway the RPM shot up way past what "3rd" was. It was a standard ratio four speed. All the other trannies I've used before with the large IBR were overdrives, but either at the factory or somewhere in the life of this tranny the guts of a non-OD tranny made it into this case.

I need an OD tranny because my little slanty Valiant was destined to be and currently is my daily driver.

I was offered a very affordable partially disassembled A-body A833 OD, but I want to make 100% sure it's an overdrive.

I assume I can count the gears on the 3/4 gears to make sure it is an overdrive. Does anyone know what that number is?

Perhaps another easier way to double check?

I need the OD in this car, I'm currently going down the freeway with the 'medium' traffic at 3000-3300 rpm and an overdrive would drop it to a managable 2200-2500 RPM.

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Scott - waywardgarage.com
Why is the rum always gone?

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Joshua

Josh, that was the first place I checked.

I couldn't find a gear tooth count or such in there, and I scrolled through it twice. I already know the gear ratios.

I figured maybe somebody knew the tooth count for just the gears on the mainshaft.

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Scott - waywardgarage.com
Why is the rum always gone?

The 3rd speed gear on an ODA833 is much smaller than the standard A833. This picture is from the article.

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Joshua

Gear tooth count is kind of tough as mopar changed at some point on the pitch and count of the teeth...I have two sets: one from a late 1975 dated A-833 OD and the OD tooth count is like 22:33...and I have one from March of 1976 but the OD tooth count is different (I'll have to count again, but I think it was 40:60)... I also have a set from a 1981 Truck and it is like the 1976 set...

Check the tooth count on the gears closest to the nose of the case, if direct it'll be 1:1...if OD you'll get a ratio either 3/4 or 2/3...

-D.Idiot