Modding a 8 lugs rear axle to a 6 lugs

[matuva]

I remeber I have read a post explaining that you can install a K2500/3500 rear end on a k1500.

The k2500/3500 being 8 lugs, there is a kit which can transform them to a 6 lugs, adding rear disc brakes at the same time.

As I am very intelligent guy, I found this very interesting but completely forgot to bookmark the thread, and the URL of the 8 to 6 lugs conversion kit...

Any of you heard about that?

 

[scottm]

I have done it the hard way a few times on my offroad race truck, by plugging the 8 lug pattern and redrilling the 5 or 6 on 5 1/2 inch pattern. It is way more work than it is worth to do it that way. Geartech makes hubs, but there are other issues and drawbacks. The main problem is the center hole in the 5 or 6 on 5.5 wheel is smaller than the diameter of the hub snout. The smallest you can get the snout is about 4.230 inch, which is still bigger than the wheel hole, so the wheels must be machined out to match. Next you have to turn the OD of the axle shaft drive flanges to the same 4.230 diameter, and use special reduced diameter socket head screws to clamp down on the drive flanges. Next you will find very little room between the lug nuts and the snout.. With 9/16 or 5/8 nuts, you must turn down the diameter of a socket to paper thin walls. I have 5/8 studs on my race truck and have cracked a couple turned sockets. If I had to do it again, I would either buy a custom 6 on 5.5 ford 9" axle from one of the millions of 9 inch builders, or change the front end to 8 lug too and get new wheels. I tried to upload pics of my custom hubs, but had problems with the uploader just now. I will try again tomorrow.

http://www.geartechhd.com/4x4-

 

[Burning oil]

I converted my Suburban to 6 lug & made my own big brake set up for the front. I just swaped all the stuff from a "heavy half ton". Reason was alot more wheel choices in 6 lug.

 

[matuva]

Very nice Leroy! How did you convert the rear axle to 6 lugs? Did you use a spacer/converter?

 

[scottm]

I suspect he has a semi float 14 bolt, not a full float 14bff.

 

[matuva]

replaced the 8 lugs full float with a 6 lugs semi float you mean?

I thought he converted his 8 lugs full float to a 6 lugs

 

[scottm]

It is much harder to convert a 14bff than what he described. Semi float 9.5 inch 14 bolts were common on suburbans. All it takes to convert a semi float is to order new axle shafts and swap them in.

 

[Burning oil]

I swaped the complete axle on the rear to a 14 bolt SF 6 lug. Front was all bolt on stuff from a 6 lug 2wd truck except I did make a big brake kit with 2 piston caliper. Had to machine the original rotor to work with a new style rotor. I have a post on it here.

 

[matuva]

By the way, my question migth look a bit dumbass, but, can you just swap a 14 bolts rear end assy on a k1500 replacing it with a 14 bolts from a K2500/3500, just as a bolt on? or does that involves fab, mods and lot of extra work to make it fit?

 

[scottm]

You can fit a 14 bolt semi float or full float axle onto a 1/2 ton truck, but only if the 14 bolt came from a 3/4 ton truck. One ton trucks have a heavier frame, and the spring-to-spring width is narrower: 40.5 inches wide, verses 42.5 inches wide on 1/2 and 3/4 ton trucks. Follow that link to Pirate 4x4 for all the info in the world on axles, especially the 14bff.

 

[Burning oil]

Thats what I did, sort of. You'll probably need different ujoint and parking brake cables. AFAIK thats it?

 

[matuva]

Thanks scottm You saved me from mistaken buy :thumbsup:
If I decide to keep the 8 lugs at the rear, can I swap the front hub assy on a 4WD K1500/6 lugs and replace them with hub assy from a K2500/8lugs?

 

[scottm]

You won't be able to just swap the hubs, because the spindles and entire upright will be larger on the 2500. I suggest searching on pirate 4x4.