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14 bolt semi float

9

90GMCJim

1/2 ton status
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I have a 90 gmc jimmy

I jumped the gun and purchased new wheels already in a 6 lug

I was planning to just rebuild the stock rear and front and go with 4.56 gears on 33 tires

I found a 82 k20 3/4 ton semi float 14 bolt axle.

Is it worth buying the 14 bolt? Will that year work? Direct swap?
It’s an 8 lug. I looked into swapping the axles and drums.
 
90GMCJim said:
I have a 90 gmc jimmy

I jumped the gun and purchased new wheels already in a 6 lug

I was planning to just rebuild the stock rear and front and go with 4.56 gears on 33 tires

I found a 82 k20 3/4 ton semi float 14 bolt axle.

Is it worth buying the 14 bolt? Will that year work? Direct swap?
It’s an 8 lug. I looked into swapping the axles and drums.
Click to expand...

it's a lot better axle than the 10 bolt that is under there without the boat anchor of a 14 FF while the 14 FF is a good axle it will be overkill on 33s. several on here have wheeled with the 14 SF with one running a doubler and 37s.
 
90GMCJim said:
I have a 90 gmc jimmy

I jumped the gun and purchased new wheels already in a 6 lug

I was planning to just rebuild the stock rear and front and go with 4.56 gears on 33 tires

I found a 82 k20 3/4 ton semi float 14 bolt axle.

Is it worth buying the 14 bolt? Will that year work? Direct swap?
It’s an 8 lug. I looked into swapping the axles and drums.
Click to expand...
If you’re gonna shop around, look for the semi float axle that is the six lug and rebuild it. Then you can keep the same wheels that you already bought.
 
Bent77 said:
If you’re gonna shop around, look for the semi float axle that is the six lug and rebuild it. Then you can keep the same wheels that you already bought.
Click to expand...
I have looked up and down. I mostly find 8 lug. is a semifloat from a k20 my best bet?
 
highly recommend. lighter and more ground clearance than the full float 14 bolt.
my 9.5 came out of a 1997 z71 pickup. 6 lug, and will be a bit wider than the original 10 bolt in the blazer... fits fine- doesn't cause any issues.

I swapped it into my 1988 K5, and the yoke for the driveshaft was fine - can't remember if I had to buy the conversion u-joint (one side of the ujoint has bigger caps), but they are avail.
I had to cut the spring perches off and weld new ones on. other than that - its running the 1997 z71 brakes and was able to use the original k5 parking brake cables.

the lug studs and lug nuts will be different than the ones on your front end... there are some threads here on CK5 with people arguing about potential damage to your wheels if you swap them back and forth between the two types of lug nuts. I run steel wheels and have never had issues, but if i were running aluminum wheels i would be tempted to drill the front out for matching 14mm studs
 
if you were to source a 9.5 out of an h2 hummer, it will have disc brakes with internal parking brake, and there is a good chance you will find one with an eaton e-locker! i always wanted one of those. it would be 8 lug though, and unsure of width.
 
I sourced mine from a 91 suburban, 8 lug, 1/2" spacer for the backing plates, 6 lug axles (new)for a 94, 3.73 g80 from an 07 pickup. Swap the metric lugs to 1/2".from an 03 tj. I've got $600 or so in it. Running 33's.
 
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I just found a 73-87 semi float with 4.56 gears 6 lug. I’ll look into the wheel stud swap once I get it
 
90GMCJim said:
I just found a 73-87 semi float with 4.56 gears 6 lug. I’ll look into the wheel stud swap once I get it
Click to expand...

The 14SF came out in 1982, and there were no 6 lug 14SFs installed in squares, so make sure it's not another 10 or 12 bolt. 12 bolt is minimal if any advantage over the 10 bolt and nowhere close to the 14SF.
 
K5Jimmy said:
Studs are 03-04 wrangler TJ.
Click to expand...

What did you use on the front? Just left the stock 7/16"?

Last I knew Dorman had discontinued the front 1/2" studs that were IMO a bit short, but designed the same as the stock 7/16. Never could find anything else that had the knurling as GM had done in the front in 1/2" unfortunately.
 
90GMCJim said:
I just found a 73-87 semi float with 4.56 gears 6 lug. I’ll look into the wheel stud swap once I get it
Click to expand...
This is your friend

Axle Identification Chart

DANA 25/27 These Danas are indistinguishable in appearance. The military Model 25 has a thick, cast cover, while the 27 and civilian-model 25s have a thinner cover, will accept taller gears, and backed V-6s. DANA 28 The alloy-case Dana 28, with...
ck5.com ck5.com
 
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GM 9.5" 14 bolt rear differential. It'll bolt into squarebody trucks from 1973 to 1987 and Blazers/Suburbans to 1991. In great shape, 4.56:1 ring and pinion, Auburn limited slip. I'm doing something a little different due to a diesel swap and no longer need this. $650 cash, no trades.



This is from Facebook Marketplace

I sure hope its right lol I have to drive 3 hours today to pick it up.
 
That’s the critter

Looking like it needs gone through. I’d see if you can beat him down on the price
 
Bent77 said:
That’s the critter

Looking like it needs gone through. I’d see if you can beat him down on the price
Click to expand...
I tried already. Got him Down to $500. It’s the gears I plan on running so I figured it’s worth it. Now I’m hoping 2 people can pick it up lol
 
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