14 bolt 6 lug

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royc

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Hello Again any thoughts on a 14 bolt sf rear with 6 lug nuts
poss/neg thoughts i have a 10 bolt now thanks roy
 

HotRodPC

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It's all Postiive if you can get it done. And it can be done, just hard to find all the parts to make it work. The best bet is usually a complete rear axle out of an 88-98 4x4 then have the spring perches cut off and rewelded.

And lets wait for someone else to chime in confirmation on the how to make a squarebody 3/4 ton axle work. I know it involves switching out the backing plates too to get it brought down to 6 lug axles. I forget the exact year models now, but it seems you get the 6 lug axles, brakes and backing plates off a 4x4 88-98. In the GMT400 series trucks, the axle widths are different for 4x4 and 2x4. 2x4 axles are to short.
 

smurph20

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We toore apart a GMT400 about 2 months ago that was a 14SF 6 lug truck. Had a 350 4L80E in it.
 

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Was it a fo buh fo? If it was, I think you can transfer those axles, backing plate and brakes to Squarebody SF 3/4 ton rear axle which I have 2 of, both with 4.10 gears. I have that ARB Air Locker 6 lug front 10 bolt too. Also been told the inner and outer axles were upgraded to chromolly shafts. If could convert one of my 14b SF to 6 lugs, I'd match it up with that ARB Air Locker 4.10 front axle and run it as a half ton and be able to keep my K10 OEM wheels. One of my K10's for sure will get 14b Full Float and 8 lugged, but I might just wait for a K5 or K20 Burb Body to do that project.
 

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Yea it was 4x4

Yes, I do believe that's the one a Squarebody owner would want to convert a 8 Lug 3/4 ton Square rear end. Or, just have the spring perches cut off and re-welded. Again, I'd wait for confirmation on that. That's info I have gotten in the last year or 2 and may not have sunk in all the way.
 

89Suburban

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Do the old perches get in the way that you have to cut them off then or can the new ones fit next to them? What about the shock mounting?
 

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I see one on CL on a 88-98 K15 with 373 gears would this rear be wider than the 10 bolt
perches line up ect... thanks Roy
 

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The perches WILL NOT line up, but it should be the same width. Those axles, and brakes should also fit a squarebody 14B 3/4 ton SF. I'm not saying for sure. I was hoping someone else would show up to confirm that. And you're sure it's a 14b SF?
 

royc

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how about a 14 bolt ff is that alittle wider axcel than a 10 bolt?
 

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I don't belive I've ever heard of a 14 bolt ff that is 6 lug. The 6 lug rears in the newer trucks are sf and not near as heavy duty as a ff. Changing out to 6 lug on a ff 14 would be a hard swap in my opinon as the axle bolts to end of hub to hold it in and bearings diferent on ends
 

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The 4x4 version of the 6-lug 14 bolt is the only one that's useful to us, whether as parts or the entire assembly. From what I've seen and done, it's much easier moving perches than it is to mix and match a bunch of parts and still have to space or modify things.

When you get the axle, you have to cut off the bump stop pads as well as the spring perches. If you are careful when removing the perches (I prefer a cutoff wheel), you can weld them back on without having to buy new perches. I decided to leave the shock mounts in place. From my measurements, all I need is slightly longer shocks and mount the shocks to the sides of the mounts rather than in the center. For strength, it will require the use of longer bolts and a spacer tube to fill the gap between the sides of the mount. The axle is not yet in the truck, but I'm confident it will go in there nicely. Oh, and the track width will be nearly equal to the front axle.
 

HotRodPC

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The 4x4 version of the 6-lug 14 bolt is the only one that's useful to us, whether as parts or the entire assembly. From what I've seen and done, it's much easier moving perches than it is to mix and match a bunch of parts and still have to space or modify things.

That's what I was thinking. Thanks for confirmation. And this is the GMT400 aka 88-98 trucks we're referring too right?
 

bucket

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That's what I was thinking. Thanks for confirmation. And this is the GMT400 aka 88-98 trucks we're referring too right?

Yes, '88-'98 trucks. The axle can be found in some K1500 trucks and light duty K2500 trucks. The light duty C2500 axle probably 'could' be used, but I think the overall width is slightly narrower than the stock squarebody 10 bolt axle. So it would look even sillier than the stock axle, and it might need wheel spacers to help the tires clear the inner wheel tubs, depending on tire size and wheel backspacing.
 

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