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Discussion Starter #1
Hey all first post but longtime member under old username. .

Ok hens tooth? I've searched hi lo and talked to Randy's and no one has heard of 3:54 gears for 14 bolt rear. .guy on ebay has what looks like the real deal 39-11 rp sets for 14 bolt..
Talk to me. .
 

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Hey all first post but longtime member under old username. .

Ok hens tooth? I've searched hi lo and talked to Randy's and no one has heard of 3:54 gears for 14 bolt rear. .guy on ebay has what looks like the real deal 39-11 rp sets for 14 bolt..
Talk to me. .
is that 14 bolt a full float or semi float ???? gears are different FF to SF.
 

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As I recall the 14 bolt had 3 ring gear sizes, the "Semi Floater" was a 9.5," the full floaters were 10.5" and 11.5".

As JT mentions, make sure whatever they are selling are for whatever size you have.

The 10.5" units I've seen have the pinion supported in a removable housing and 11" brake drums, the 11.5" units had 13" drums and the pinion loads into the axle housing from the back.

All from memory of course, just make sure the parts will fit yours before you spend $$$
 

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Discussion Starter #5
The ff is 10.5 and has the second pinion support bearing. I do know as much as the next guy about the venerable 14 bolt. My reason for posting was not about the ring and pinion size it was whether the 10.5 was offered in a 39 11 3.55 or 3.54. I'd bet my shorts it was never offered or made. Anyone need a pair of shorts? ?!
 

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Discussion Starter #6
Apparently the aam and the corporate are made by the same company. Some parts do interchange. The rp will work. Not one person I have talked to or read online has heard of a 3.54 or 3.55 ratio for a 14 bolt.. I found a dana 60 hp 3.54 and have a 14 bolt 3.73. Prefer the 3.54..
 

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Yukon Gear offers a 3.21 and a 3.42 Gears for the 10.5" 14-Bolt FF
 

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Don't be confused with the AAM 10.5 FF found in Dodges, or the AAM 11.5 FF found in Dodge and GMs. Gears & diffs are different than the traditional 'Corporate' 14bolt (also found under the AAM name) thats been around for years. The Corp 14bolt is easily differentiated from the others by the removable pinion housing.

Closest you will find is 3.42. If you need to match a front axle with 3.54/3.55 I would look around for a D70 in stead of the corp 14bt.
 

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Did you end up buying a set? I did, took a chance on it. It definitely is the real deal. apparently 2011-16 2500 express vans came with the aam 10.5 14bolt and 3.54 ratio only. I would like to buy another set for a different truck, but can't seem to find them anywhere other than buying a whole rearend. I need to check with chevy and see if they sell them I guess.
 

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14 Bolt FF 10.5"

My k2500 Suburban came w/8.6+ GVWR & has a 14 bolt ff 10.5" R&P it has 13" x 3.5" drums.
 

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My k2500 Suburban came w/8.6+ GVWR & has a 14 bolt ff 10.5" R&P it has 13" x 3.5" drums.
Ok what is your point? we are talking specifically about the 3.55 gear ratio, which is only available in the vans.
 

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Point?

Ok what is your point? we are talking specifically about the 3.55 gear ratio, which is only available in the vans.
I didn't quote it but it was post #4 I responded to brake drum sizes.............
 

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Discussion Starter #13
Did you end up buying a set? I did, took a chance on it. It definitely is the real deal. apparently 2011-16 2500 express vans came with the aam 10.5 14bolt and 3.54 ratio only. I would like to buy another set for a different truck, but can't seem to find them anywhere other than buying a whole rearend. I need to check with chevy and see if they sell them I guess.
So you have 14 bolt of gm? The gears worked in the ff gm 14 bolt ok? If so a definate bonus for the 14 bolt crowd..
 
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