14 bolt FF swap

[Mr. 250r]

After getting my D60 swap done which didn't go as i hoped but that's part of it, I decided to swap out my 14bolt semi-floater for a 2006 14bolt full floater with some help from my4by2's build thread i decided it was basically possible and i wanted disc brakes from the factory and the parking brake not a bolt on setup without a parking brake or even using the transfer case brake or anything along those lines. So far i've only messed with checking the gear ratio, brakes and seeing if my 16.5in wheels would fit and seeing if some free H2 wheels would fit as well even though they're ugly to me

[67mater]

another IL guy! I put a full floater in my 67; watch the perch spacing as they may be different. I had to cut off the old perches and weld new ones on. great chance to correct pinion angle though!

[Doug_J]

I have a 84 3/4 ton I was thinken of doing the same swap for the disc brakes. what are you gonna have to do to make it fit?

[Hoods69BadBowTie]

That is defiantly a good idea and a cool swap. I am curious to how it turns out. Good luck on it and keep us update

[Mr. 250r]

I had to stop the swap for awhile because I was paying stuff off and bought a camaro but sold my other mud truck so the swap is back on and the measurents put it a few inches wider as for what's needed to put under like a stock setup would really only be the emergency brake cable bracket which I found one so ill put some stuff up this week probably
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[Doug_J]

So when you say wider is it both the shock and spring perches that need moved in or what?

[DirtyLarry]

Yeah, the GMT800 10.5 and 11.5 full floating rear axles are about 3” wider (hub to hub) than the old square body style 10.5 (14 bolt FF). In my opinion, the wider axles in the back of an older truck just doesn’t look right. The GMT800 spring perches are also in the wrong spot for a direct bolt in to an older truck.

A while back someone mentioned there as a fabricator that was making a kit where the rear disk brake setup of from a GMT800 truck could be retrofitted onto an older 10.5 axle but I forgot who that fabricator was. There is really no benefit of using a later full floater other than the disk brakes. If those could be bolted onto an older 14 bolt FF that would be a much better deal for many of us.

[Doug_J]

Well running it wider wouldnt be bad because it would even it up with the front axle. I would think also that another good thing about it is alot more of the 3/4 and 1tons come with limited slip so maybe a plus on that but I was trying to figure cost, salvage yrd is gonna cost $300 to $400, disc brake kit is about $300 and up or get the brackets and pice it together.

[Mr. 250r]

Originally Posted by Doug_J

So when you say wider is it both the shock and spring perches that need moved in or what?

To be exact I think each perch needed to be moved in 3in a piece and the shock mounts need flipped to the other side and moved a little it has the shock mounts like an old full floater mounts opposite of my semi floater, the other things is my semi floater banjo bolt fits the new brake lines so you can re-use that. The parking brake SHOULD work by using a newer trucks adjustment bracket which I found at the shop as pictured. Still gotta get pinion angles and see if the u-joint fits from my old axle

Originally Posted by DirtyLarry

Yeah, the GMT800 10.5 and 11.5 full floating rear axles are about 3” wider (hub to hub) than the old square body style 10.5 (14 bolt FF). In my opinion, the wider axles in the back of an older truck just doesn’t look right. The GMT800 spring perches are also in the wrong spot for a direct bolt in to an older truck.

A while back someone mentioned there as a fabricator that was making a kit where the rear disk brake setup of from a GMT800 truck could be retrofitted onto an older 10.5 axle but I forgot who that fabricator was. There is really no benefit of using a later full floater other than the disk brakes. If those could be bolted onto an older 14 bolt FF that would be a much better deal for many of us.

That is probably a cheaper solution for everyone but I wanted the finned housing because mainly the look and the FF I have is rusted and slightly pitted and I just didn't want to deal with that but that's just me and as far as the look my4by2 has a newer housing and if I remember looks fine been awhile though

Update - I grinded off other side as well and started wire wheeling the housing because I'm just gonna paint it but still gotta mig in the cuts and get the truck fixed because its going out this weekend most likely with the semi floater
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[Mr. 250r]

Here's the picture of the bracket i was talking about from a newer trucks e-brake cable

[old yelr]

The brackets that DirtyLarry are talking about are made by a company called right gear. You can find them at www.rightgear.com. I'm planning on doing this swap in the spring and I was looking at using the brackets and swapping the late model disk setup onto my 10.5 FF rear end in my 1979 GMC. I called them and found out that they cost $90 each plus shipping and you still need to get the brake setup and cables etc. I got a complete disc brake rear end (GT5 G80) with cables and brake lines etc out af a 2004 2500HD truck for $200.00 from a local wrecker so why would you pay for the brackets when you can get the whole rear for the same price as the brackets.
I also measured the rear end from wheel mount surface to wheel mount surface and it measured 68.5" and my old one is 67.0" so it's only a 1.5" difference. No big deal IMO.
I'm going to be running the newer style 2500 alloy wheels (10 hole) so with the offset of the newer wheels it actually works in my favour that the rear is wider.
Hope this info is useful for someone

[Undone]

Originally Posted by old yelr

The brackets that DirtyLarry are talking about are made by a company called right gear. You can find them at www.rightgear.com. I'm planning on doing this swap in the spring and I was looking at using the brackets and swapping the late model disk setup onto my 10.5 FF rear end in my 1979 GMC. I called them and found out that they cost $90 each plus shipping and you still need to get the brake setup and cables etc. I got a complete disc brake rear end (GT5 G80) with cables and brake lines etc out af a 2004 2500HD truck for $200.00 from a local wrecker so why would you pay for the brackets when you can get the whole rear for the same price as the brackets.
I also measured the rear end from wheel mount surface to wheel mount surface and it measured 68.5" and my old one is 67.0" so it's only a 1.5" difference. No big deal IMO.
I'm going to be running the newer style 2500 alloy wheels (10 hole) so with the offset of the newer wheels it actually works in my favour that the rear is wider.
Hope this info is useful for someone

90.00 each or for a pair of the brackets?

[Mr. 250r]

Well had someone posted the link for said product I most likely would have found it lol although I couldn't find it on their website but if it works for anybody that's a plus but I still wanted a finned housing ;-p
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[old yelr]

Yeah, I looked it up on their site too and they don't show it but if you call they will know what you are talking about I found it on Four Wheeler magazine in the July 2011 issue under the Parts Rack-New Products section.

http://www.fourwheeler.com/departmen...#ixzz1OeVOKTYn

Maybe I got a smokin deal on this rear end and it would be more feasable for someone to use the brackets I'm not sure.

Anyway, I'm new on here and for the last few weeks I've been checking out some of the amazing builds and trying to absorb as much info as I can on all the tech and swaps that people are doing and I think this is an amazing resource and it has given me some much needed inspiration and motivation to finally get moving on my project!

Actually, the reason I stumbled onto this site in the first place is because I want to swap an NV4500 into my truck and I happened to find DirtyLarry's build thread and since then I've been addicted to this site

Keep up the great work!! It looks great and I'm definately hooked

[Mr. 250r]

Really good find wish i still had the subscription to the magazine but got tired of the stuff in it would've helped me though lol but then again if it was july's issue i still would have missed it, still good find it will guaranteed help someone else ill hopefully get it done by thanksgiving got some stuff to do by then

[old yelr]

Awesome! I will definately keep an eye on your swap
Hope all goes well.

[mcmlxix]

I also had the same idea... First I bought the 11.5" AAM rear and it was just overkill... plus it only had 3.73 gears.... Then I found a 10.5" AAM rear with the gears I needed, cheap but from a wrecked truck and has issues. (cant remove one of the axle shafts) I also went this route to have a factory discs with drum in hat parking brake.... I am also in the middle of designing a front Dana 60 brake bracket to run late modle dual piston calipers and 14" rotors...

How long did it take for you to get the perches? ... and what size did you order?
The tube on the AAM seems a littel larger then the old school 14BFF....

[Mr. 250r]

I didn't want the AAM 11.5 but the 10.5 I don't really consider it an AAM I think its just an updated FF lol but as for the ballistic perches I think it took about a week and size was the same as the old ones, which I think is 3in wide but has 3 holes and I had to drill the middle out to fit my lift block pin which was weird but as for the axle tubes I think the OD is the same because I'm pretty sure the new perch fit perfectly on the one

After this I have an old FF I couldnt sell which i got with my d60 so I'm gonna keep it and look into making it a front axle
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[Mr. 250r]

FINALLY got it all done but i kind of had to throw the brake lines together and did not get the e-brake hooked up or bled the brakes 100% correctly, but other than all that its done and in, here's some pics of the welds which kind of look like 6010's but they are all mig and i suggest taking off the brake assembly etc makes it much easier i welded it underneath my truck and should've had a light but it worked out fine. And the lincoln mig welder was 32 years old lol nearly twice as old as me and works better than the 10,000$ millers we use at school and is the only good lincoln i have used

You can also tell the driveshaft sticks out about 1/2in farther than it used so ill need to get a new one and it will need a "jump joint" u-joint as well, and as for the pinion angle i did NOT tilt it all kinds of up, just a little and it is perfect as i only have a 4in suspension maybe 6in later but i doubt it, don't like jumping into it now

Still gotta take the shock bracket to school and make another and cut it down some as the new ones are about 8in long as compared to the 5in old one so its drive able into the parking lot and that's as for as it goes for about another.... month

[SunSoaked]

Originally Posted by Mr. 250r

FINALLY got it all done but i kind of had to throw the brake lines together and did not get the e-brake hooked up or bled the brakes 100% correctly, but other than all that its done and in, here's some pics of the welds which kind of look like 6010's but they are all mig and i suggest taking off the brake assembly etc makes it much easier i welded it underneath my truck and should've had a light but it worked out fine. And the lincoln mig welder was 32 years old lol nearly twice as old as me and works better than the 10,000$ millers we use at school and is the only good lincoln i have used

You can also tell the driveshaft sticks out about 1/2in farther than it used so ill need to get a new one and it will need a "jump joint" u-joint as well, and as for the pinion angle i did NOT tilt it all kinds of up, just a little and it is perfect as i only have a 4in suspension maybe 6in later but i doubt it, don't like jumping into it now

Still gotta take the shock bracket to school and make another and cut it down some as the new ones are about 8in long as compared to the 5in old one so its drive able into the parking lot and that's as for as it goes for about another.... month

Mr. 250r

So what did you end up with as far as the rear brakes? I'm confused because you talked about late model disc's, the brackets from Right Gear but kept mentioning wanting a "finned something". When I think finned, I think drums.

I really want to convert my 87 14FF to disc but it has to have some sort of e-brake other than the cadillac caliper I've heard about.

Some pics of the final setup would be awesome

[Mr. 250r]

Ah ill explain the confusion the finned housing was brought around in I think 1988 when the new body styles came out, I have a 2005HD FF if you look at the pictures on the yoke side oppsite of the cover starting at the top there's metal fins going down the housing I'm pretty sure made to cool it down while moving

As far as the e-brakes I haven't hooked them up as its a matter of finding a correct late model e-brake line which I'm too lazy to do

Now the right gear company sells brackets to use 2002 and later brake setup and I can only assume the OEM e-brake setup, but I found that out too late though

What pictures do you need ill get them this weekend
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[old yelr]

Any updates?

[Mr. 250r]

There is no updates on the axle except I might put a pinion guard on other than that its been done for a long time as far as the truck updates those I will post in the build thread and I kinda lost interest in the truck so I stopped working on it but now I'm going to try and get it finished
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[old yelr]

The flanges are different from the old 14FF to the new ones, that's why the brackets are necessary in order to bolt the late model set up onto the older rear ends. If you get the brackets from rightgear you will still need to find the late model disc brake setup.