14 bolt Full-Float conversion u-joint?

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RichLo

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I just picked up a used 14FF on a local online auction that I want to put in my snow plow truck and I'm wondering how to source a conversion u-joint? It currently has a worn out 1/2 ton 10bolt in it and I want to reuse the same driveshaft.

Thanks!
 

Supercharged111

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Just go to Napa and get a crossover between your truck and the donor. They have a chart in a book to look up the number.
 

stutaeng

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My brother did a 10 bolt to 14b 9.5 SF 6 lug. I can ask him, but not sure if it's the same as yours...I think he just did an internet search and found it, LOL. And picked it up at the local parts store.

The NAPA crossover refence guide sounds like a better idea!
 

RichLo

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Cool, I never knew they had a chart for common swaps.

Online searching seems to have a lot of old part numbers that don't work in the parts stores anymore. They must change part numbers whenever they get a new vendor or something.
 

stutaeng

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I've seen some tables from manufacturers that also list the measurements for the U joints, like cap diameter, out-to-out measurements, etc.. Get some dial calipers and check yours and that way you will have a guaranteed fit.

Also, try to get the U joint with that greaseable zerk fitting it is available. They ususally make the same u joints with and without the zerk.
 

RichLo

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So, I was originally going to use this on my plow truck and just run 8-lug in the back and 6-lug in the front with the same size tires. BUT the more I'm thinking about it I have a NV4500 and built small block that I'm going to eventually swap into my street truck and this axle is already 4.10 gear...

My question, is there any reasonable way that I can run factory 6-lug wheels on a full float 8-lug axle? or would the adaptors be so thick the tires would stick out look like roller skates?
 

stutaeng

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Something has to be custom machined for that to happen. I'm not sure how this guy did a 14bFF 6 lug, but he did:

https://www.performancetrucks.net/f...-22/10-5-full-floating-14-bolt-6-lugs-528236/

I'd look into the Jeep forums and the 4x4 Pirate forum as well. 14bFF is very popular with those guys that run big tires, not sure if they convert to 5 lug or 6 lug, or if that even is the same patterns as our generation trucks.

Have you tried looking for the 14b 9.5 SF version with 6 lug? 2500 6 lug are other there. I just saw an '89 listed here yesterday with a tranny blown out for $1,000 could probably negotiate down I'm sure. I've seen these get parted out also.
 

RichLo

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Thats cool, it looks like a custom hub and the wheels had to be opened up to go over the hub.

I got this axle at a smokin deal and just thinking of options about where to use it. Otherwise I would be looking for a 6-bolt semi-float instead.
 

stutaeng

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Also, a GMT900 truck with 6.2 I've read also has the 6 lug pattern on a 14 bSF...with disc already, LOL. Although that is obviously not a direct plug and play swap and those will most definitely have numerically lower gear rations since they came with 6 speed tranny. Also, that was not a cheap option on those trucks, just the really high trim trucks, so won't be easy to source either... read: not worth it.

On the 6 to 8 lug adapter option, some guys run some spacers just to increase the rear track width since the rear on these trucks was narrower than the front. Won't the lug adapters basically do the same?
 
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