Swap 14 bolt Full Float to 14 bolt Semi Float !!!

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HotRodPC

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For those who wondered like I did... and now I know. I assumed it would be, and is. The pinion lengths are different between the 14b SF and 14b FF. I took the FF out, installed the SF and it appears I'll have to install the driveshaft out of the truck that had the SF cuz the FF driveshaft is 2 - 2.5 inches to long. I've got it slid all the way forward and it just barely won't go into the pinion yoke. And even if it would, there is no room for expansion, so I figure to have some room to move around, it's prolly about 2 inches to long.

However, I have a feeling, if you were going the other way, from a 14b SF to a 14b FF, I'd just about say that gig will work fine. I'm pretty sure there is 1.5 - 2 inches to play with if you wanted to extend your FF driveshaft to reach the SF pinion yoke and you'd be OK without worry of dropping the rear drive shaft off the front drive shaft splines.

I have to get at least 1 U joint and a carrier bearing installed on the SF driveshaft before I install it. If and When I install the 3.73 FF in this truck, i'll try the SF driveshaft and confirm that it can be used going from 14b SF to 14b FF.
 

highdesertrange

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just curious here. why are you pulling a ff and installing a sf, posi, locker? highdesertranger
 

HotRodPC

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Sold the 3.21 ratio Full Floater. The SF is just going in temporarily. It's a 3.42 ratio peg legger. I've got a 3.73 FF that will eventually go back in it, but not until I get a bearing kit, seals and want to install Detroit Locker. I might even end up just lunchboxing it since I won't have mega hp and plan on a stock 31in narrow tire.
 

89_3&3

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Do you have a ball joint press that in a vice works great for pushing u joints
 

HotRodPC

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I use a regular bench vise and big sockets for Ujoints. Never had a problem doing it that way.
 

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All you need is a hammer and a couple of pieces of wood to rest the cups on. Then lightly tap down on the shoulder of your shaft. Slides right out. Use a c clamp to put them back in or just go easy with the hammer and tap them back in.
 

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want to install Detroit Locker. I might even end up just lunchboxing it since I won't have mega hp and plan on a stock 31in narrow tire.
the ff Detroit is a lunchbox locker...
 

HotRodPC

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Pretty Much so. May as well be, but more referring to the cheaper units. Lock Right and that Wtf is my mind drawing a damn blank.... A yukon system IIRC.
 

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Used to be the 14 bolt Detroit was the cheapest locker available.
 

HotRodPC

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Used to be the 14 bolt Detroit was the cheapest locker available.

I think now you're buying the name. The Yukon, I think it's called Grizzly, is almost identical in appearance and also has been talked up real good a few times I've seen. And it's a bit cheaper than the Detroit. In the 14b Full Float, the way you have to split the carrier, there really isn't to many designs you can go with unless you change the whole carrier. Then again, I guess that goes for all the rest too.
 

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