14 Bolt SF 8 lug to 6 lug Conversion

[callmej75]

First of all this is my first post and I apologize if this has been covered before! I have been googling a lot of things on this SF axle I purchased and its becoming a headache now. My plans were to swap it in my 84 K10 that I have toasted the pinion gear in. So here goes my story...

I purchased a 14 bolt SF 8 lug from a junkyard out of an 86 3/4 ton a few days ago. I would have gotten the 6 lug from a newer truck and moved the spring perches, but no welder here and I don't trust anyone around here to do it correctly. I have new rims and tires on the truck, so I wanted to retain the matching 6 lugs. I am upgrading to Yukon 4:56 gears, Yukon LS, and Yukon axles. Plus Id like to do a disc brake conversion too.

First...to the axles. Purchased everything from Randys Ring and Pinion and their customer service was great. I asked for 6 lug axles. They said no problem....well they shipped me 8 lug axles. So i called and told them 6 lug again, and after looking at it extensively, they could get me some axles that are 6 lug, BUT the rep said they are about 3/4" longer than the stock 8 lug.

So here is my question...do I have to send these off to be cut 3/4" and be resplined?

Well...2 questions actually. Sorry guys! Is there a disc brake conversion kit made for these SF rearends? I see brackets made for the FF, but not the SF. I have read you can piece the calipers and rotors together as well? Of course some things I read are pertaining to other vehicles and not my rear and years I'm wanting.

Thanks for any help I can get here, or any other suggestions!

 

[crazy4offroad]

All the 8 to 6 lug conversion parts I've seen were for the Dana 60 and 14-bolt full floater. First thing you need to ask yourself is "will my 6 lug wheels even fit this axle after it is converted?" If you have 15s and the 14 sf ran at minimum 16s you could run into problems even before the machinist rakes you over the coals. I used to have a bunch of bookmarks for conversion parts but many of them are now dead or show "under construction". It would be probably cheaper and easier to convert the front to 8 lug to match the rear using factory 3/4 ton parts, sell your wheels and tires and go with 8 lug wheels.

 

[bucket]

There are disc brake kits for the 8 lug SF and I know at least one person has converted one to 6 lug using the '88-'98 parts. Couldn't tell you about doing both.

Having shafts the right length would make it a simple swap if you were willing to keep the drums. What's the cost on having them resplined?

 

[callmej75]

Yeh I would think someone has done these before? They are $125 for the pair, doesn't include shipping to and from Moser. I found the weld on bracket from RuffStuff for the calipers. Talked to the tech and he said the 3.25" are the ones I need.

 

[callmej75]

All the 8 to 6 lug conversion parts I've seen were for the Dana 60 and 14-bolt full floater. First thing you need to ask yourself is "will my 6 lug wheels even fit this axle after it is converted?" If you have 15s and the 14 sf ran at minimum 16s you could run into problems even before the machinist rakes you over the coals. I used to have a bunch of bookmarks for conversion parts but many of them are now dead or show "under construction". It would be probably cheaper and easier to convert the front to 8 lug to match the rear using factory 3/4 ton parts, sell your wheels and tires and go with 8 lug wheels.

I was beginning to think the same thing you are....but i kept my mind from wandering and causing more confusion!

 

[callmej75]

After looking up the various parts needed, I will be able to retain the 15" rims I have on now. Ive attached the weld on bracket for my axle that a tech from RuffStuff said would work. Its for the 3.25" diameter. The rotors will be from an 88+ Chevy 4x4 front.

 

[callmej75]

Here is the 14 bolt painted up now

 

[callmej75]

Here is what it is going in

You must be registered for see images attach

 

[Derick C.]

Nice truck

 

[callmej75]

Nice truck

Appreciate it

 

[Derick C.]

I will be doing a similar axle swap but I want to go 8 lug.

 

[callmej75]

I will be doing a similar axle swap but I want to go 8 lug.

Do it...and go FULL FLOATER! I have been having bolt on headaches with this one and finding things to adapt.

 

[Derick C.]

I have a SF from another suburban

 

[callmej75]

I have a SF from another suburban

Ahh...well hopefully I can post up something here helpful for ya at some point

 

[callmej75]

I got the 6 lug axles in yesterday and rotors from the front of an 88 1/2 ton 4x4. Test fitting them, I noticed the usual flange of the axle hitting the inside of the rotor and would not seat. So I dropped off the axles and a rotor at a machine shop to have them turn down the outside flange to fit the rotors. Picking those up next week