FMJ Differentials

Camtron

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Fantastic information. Exactly what Ive been looking for. I just picked up a 8 1/4 from a 87 Dodge diplomat police car to swap out my 7 1/4 . Is the firm feel kit a direct bolt in? Thanks again.
Are you going to be using the AHB 8.25” or getting the jeep rear end? I purchased a AHB rear from a member here and rebuilt it with SureGrip and 3.21 gears. The AHB 11” drum brakes stop real nice too.
 

greyghost

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I'm a little late to the party but I was curious if ZieglerSpeed ever got his pinion bolt out from about 5 years ago!! LOL!! Actually I was reading about the rear end swaps and I was curious why I never hear anything about the Mopar 9 1/4". I found this interesting piece in Hemmings Motor News. I'm sure many here will disagree with this but I still found it interesting mainly because I have one of these in my '79 300 parts car plus an empty housing stored in my trailer. https://www.hemmings.com/stories/article/chrysler-9-1-4-inch-differentials
 

Mikes5thAve

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You don't hear much about 9 1/4 when it comes to these cars because they came in bigger vehicles and don't fit. Not sure what the Dakota/Durango size is tho.

They do come up more often in other applications where they are a direct swap.
 

Aspen500

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My '96 Dakota rear is called an 8 3/8" but, to me it looks exactly the same as 8 1/4", aside from the speed sensor. Like a car, the axle is above the springs (4x2 anyway, unsure about 4x4) so the perches are in the right location.
 

80mirada

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The 8 1/4 went to and 8 3/8 ring gear in the early 90s. The larger gear and limited slips are all compatible. Just have to watch for the even later 29 spline axles
 

Aspen500

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The 8 1/4 went to and 8 3/8 ring gear in the early 90s. The larger gear and limited slips are all compatible. Just have to watch for the even later 29 spline axles
That and, 92 and up, you need different axle shafts since they went to that stupid 6x4.5" lug pattern, for some unknown reason......
 

UNKIE

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I have installed more aftermarket axles than I could ever remember and they have all had the sealed green type bearings. As for as not holding up as well as the tapered roller bearings I believe that to be true because most everything now has the sealed bearings and they seam to start failing at 100K including the ones on the rear of my Expedition.
what 8 1/4 will fit the F M J bodies / LeBaron/ Caravelle coupes
 
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