Are ff14 bolts really necessary

[K5 dude 350]

i have a 91 half ton suburban and i plan on putting a 6 inch lift and 35 on by this summer. I plan on wheeling alot but i dont really beat the piss out of it do i really need a 14 bolt and a dana 60 or will the 10 bolts hold up as long as i dont really get on it? i ask this because money is always as issue for me

 

[K5 dude 350]

oh and my burb will never see any rocks, just mud.

 

[Greg72]

35's aren't THAT big of a tire, but the problem you should be worrying about is what happens if you DO break something? Up front, snapping an axleshaft means that you can still limp it home....snapping a shaft out back means that your wheel is going to fall off and leave you stranded.

The biggest benefit of the 14BFF is the full-floating hubs. If you snap an axleshaft (not likely) the wheels will still stay attached to the truck, and you could still get home in FWD.

At the very least, I'd look into any aftermarket kits that will allow you to convert the rear axle you've got to a full-floater, or at least something like a "C-Clip eliminator" kit to keep those wheels in place no matter what happens.

 

[jt512]

14 bolts are realitivley cheap and easy to find, I would at least upgrade the rear and maybe just convert your 10 bolt front to 8 lug to match. Heck it's actually easier and cheaper (at least from what I have found) to convert to rear disc on a 14 bolt then it is on a 10 or 12 bolt.


Just think about how bad a 35" tire coming off and getting jammed up in your wheel well or having it pass you going down the road will ruin your day (and mess up your burb).

Just my $.02 but if it were me, I say 14 bolt

 

[stockk5]

i think you will be just fine on the stock axles. long as u dont hit the rocks n get airborne

 

[dremu]

At the very least, I'd look into any aftermarket kits that will allow you to convert the rear axle you've got to a full-floater, or at least something like a "C-Clip eliminator" kit to keep those wheels in place no matter what happens.

IIRC, such kits will cost several hundred bucks. A 14bFF, 8-lug outers, and new wheels is prolly cheaper

-- A

 

[Russell]

Around here a 14 bolt costs like $150 - $200, pretty cheap insurance premium as far as I am concerned!

Up front I'd just convert the outers to 8 lug for another $200 and run it that way. I ran 35" boggers on 1/2 ton diffs without any trouble, but breaking a rear axle shaft ways always a concern.

 

[blazinzuk]

I think the reason so many people swap them in cause they are cheap and stupid strong. Mud can be hard on stuff too ever spin your tires then hit a high traction surface.

I think you will be fine on 10 bolts as long as you dont' lock it. Look for a semi float 6 lug 14 b for a strength increase with out buying new wheels

 

[mad_burban]

I say go with the 14ff thats what im doing now on mine. Ive beat my 10 bolts pretty hard including getting the truck airborne but if your gonna lift the burb throw the 14ff under it. I like my wheels to stay on my truck. Just my .02

 

[80' 427]

What gears do you have now? Another benefit is they usually come with deeper gears and are cheaper to swap then regear the 10s.

 

[thatK30guy]

i have a 91 half ton suburban and i plan on putting a 6 inch lift and 35 on by this summer. I plan on wheeling alot but i dont really beat the piss out of it do i really need a 14 bolt and a dana 60 or will the 10 bolts hold up as long as i dont really get on it? i ask this because money is always as issue for me

A D60 is more a want than a need. You will get by just fine with the 10 bolt front if you either swap the outers out to 8 lug or swap a complete 3/4 ton front under it.

You don't mention the type of mud running you do. There are different ways to classify "mud".
How hard are you on the skinny pedal? Is the terrain flat and muddy or hilly and rocky? Whats your motor like? Tranny? If you're driving a stock vehicle, 3/4 tons will be more than enough for you.

As the others above me said, use a full floater in the rear. A semi floater will leave you stranded and you will either piss off yourself or your friends.

The choice is very simple to decide. Tell us more about your driving habits and what the terrain is like in your areas of wheeling.

 

[resurrected_jimmy]

As others have said, the 10 bolt front will be fine. I had a 91 burb on 33's and like you did mostly mud and beach running. I broke 3 10 bolts. Get the 14FF out back. Burbs are just too heavy for the 1/2 ton rear axle in my opinion.

 

[scouthead]

I think you will be fine on 10 bolts as long as you dont' lock it. Look for a semi float 6 lug 14 b for a strength increase with out buying new wheels

yeah, just run the ten bolt. If it has a gov-lock, then start axle shopping soon after the 35s. If not, just keep an eye out for bent axles, diff noises, and don't drive like a madman with a pissed off right foot.

My rear 10 bolt had the gov-lock and 60,000 miles on it. I abused it a couple times a week for six months before it actually locked up. (manual trans and 33x12.50 tires.)
Replaced with the semi float 14. Got to keep my stock ralleye wheels.

 

[K5 dude 350]

I think im just going to put a ff14b out in back and the the 8 lug conversion to the front. so some questions. what needs to be done to get a ff14b to work in my burb. Im assuming the spring perches will be in the right spot if i get it out of a full size chevy, but what about brakes and driveshaft. Can some one give me a link to a 8 lug front swap.

Thanks

 

[dremu]

I think im just going to put a ff14b out in back and the the 8 lug conversion to the front. so some questions. what needs to be done to get a ff14b to work in my burb. Im assuming the spring perches will be in the right spot if i get it out of a full size chevy, but what about brakes and driveshaft. Can some one give me a link to a 8 lug front swap.

Thanks

http://coloradok5.com/8lugconversion.shtml



For the rear, your best donor will be a similar year 3/4 ton 4wd. That would bolt up, with the addition of a conversion U-joint.

A 2WD donor means you'd have to cut & reweld shock mounts.

A 1-ton donor means you'd have to cut & re-weld spring perches (more work than the shock mounts) or do something creative with shackle flips.

The parking brake changed in ~84, so if your K5 is an 84-91, stick with an 84-up donor to have the cable types match up. (Conversely, if yours is earlier, try and get an earlier donor.)

Note that lots of 80's 3/4's have the semi-float, so learn the diff shapes

http://coloradok5.com/axleguide.shtml

-- A

 

[Desert Rat]

One thing I learned with my Blazer project is that your running gear can have an affect on your power. I swapped in a Corp14ff in the rear, D60 up front w/ Dedenbear knuckles, crossover steering, doubler transfer case, and HAD shafts with massive U-joints. All of this adds a lot of weight and now my engine just didn't have a ton of power to push it all. I have a crate 350 that came with an Edelbrock Q-jet and intake. I added Doug's headers, an MSD HEI, and just put in a torque cam which helped a lot. Of course I also have a full roll cage but I also gutted the interior. So, in summary I would also consider your engine and whether you currently have enough power prior to adding a whole lot of rolling mass and more weight.

 

[original balzer]

As others have said, the 10 bolt front will be fine. I had a 91 burb on 33's and like you did mostly mud and beach running. I broke 3 10 bolts. Get the 14FF out back. Burbs are just too heavy for the 1/2 ton rear axle in my opinion.

I agree with this my 91 burb was all stock with 31" tires a new trans with a shift kit and even the old worn out engine busted the spider gears not once but 3 times. The weight of the burb just seams too much for the tiny 10b rear. I would imagine you will have to be extremly gentle on the 10b rear under a burb with 35's.

By the way I upgraded to the larger gears the first time I broke them.
My brother now owns it and swapped in a 12b and a 385hp 350 and has already broke the rear end twice. (although the 12b came out of a mud racer so I think its been abused and is possibly bent the housing)

 

[K5 dude 350]

cool guess im going to go junkyard hopping for a 14bolt. what the difference between the 1 ton and the 3/4 ton 14 bolts

 

[SkulzNBonz]

Spring perch width, and shock mount location because of said spring perch width. The width on a one ton requires you relocate the perches to put under a 1/2 ton truck, whereas the 3/4 ton 14bFF requires no modification whatsoever.

John

 

[82355]

This is with 31x10.5x15" tires.

For as stupid easy as swapping in a full floater is, I don't know why you wouldn't? (I did)

Martin