I compiled them all into a single 14 bolt manual in pdf format

The 14bolt is found in a huge number of GM 4x4 pickup trucks and vans, 3/4 and 1 ton, from the 70's right through until at least 2000. You can find it in:

• 73-96 C20, C2573-00 C30, C3573-00 G30, G3573-00 K20, K2573-00 K30, K3584-88 CUCV
• 88-91.5 V30

As well as a whole lot more cab and chasis trucks, delivery vans, etc.

Being a full float (FF) axle, it of course has full floating wheel hubs and axle shafts. I simply love full-float axles, and would never go back to running anything but a FF axle, for some very good reasons:

• The axle shaft does not support the weight of the vehicle, but merely transmits torqueBecause of the above - FF axle shafts are not subject to bending loads like semi float (SF) axles are and can therefore be made of harder materials making them capable of carrying greater torque loadsIf you should ever break a rear FF axle shaft, you will not loose the wheel too.If you need to change a FF rear axle, it is extremely easy and simple to do.The hubs run big, strong, common, reasonably cheap wheel bearings, races, and seals (14b Dana 60 and 70 bearings, front and rear, are all the same)
• The wheel bearings are not pressed onto anything, if need be they can be removed and replaced with nothing more than a screwdriver and big hammer.

Before we delve deeper into the 14bolt, let's just talk about why this is such an awesome axle. It has a number of distinct features / advantages:

• Gear strength - 10.5" ring gear, 1.750" 30 spline pinion, huge 2 piece carrier made of 8620 Heat treated alloy steel, extra pinion bearing support Shaft strength - 1.5' 30 spline full floating shaftsHousing strength - massive cast iron center section, 3.25: x 0.5" tubesComes in two widths - 63" and 67" wms-wms, easily converted from one to the other (shafts are common)Removable pinion support, unbolts from the rest of housing, makes for easier gear setupDiff housing has built-in threaded carrier pre-load adjusters, makes for easier gear setupBecause the carrier is so large and strong, a "full" detroit locker fits in the stock housing, and is therefore easy to install without gear setup changes, and is much cheaper than other 1 ton FF lockersPinion yokes commonly available for 1350 series u-jointsFairly commonly came stock with 4.10 and 4.56 gears and Detroit LockersCheap and easy to find, buy, and buildEasy to convert to disc brakesEasy to "shave" for 2" inch gain in clearancePinion length shorter than other 1 ton ff rear axles (D60, D70), for improved driveshaft length and anglesLarge ID spindles
• Common spindle nut threads with Dana60 front axle, meaning only one style of spindle nut and socket need be used / carried

Of course, there are drawbacks too:

• Lack of traction aiding differentials - especially spoolsLack of available gearing - only down to 5.13Lack of aftermarket alloy axle shaftsCarrier break. Most 1 ton ff also have a carrier break though, so it's relative Uses a crush sleeve to set pinion preload heavyLow clearance in stock form
• Heavy in stock trim

Overall, I think they are a superb choice for a heavy duty off-road machine. I'll let H8Monday, from the PBB, sum it up, as he does so well. H8 is a rock crawling competitor, devout throttle crazy maniac, who runs a 14b behind a very healthy 5.0. He says:

"One of the best things about the 14 bolt, other than they are dirt cheap and nearly indestructible, is the cost of building them. It is very common to find them with 4.56 gears, and often axle shops and junk yards will have used factory sets. They are very easy to set up, because they have an adjustable backlash. Spare axle shafts are nearly free, and the shafts are the same for the C&C or standard version. Not that spares are usually necessary with a 1.69" axle shaft diameter, (splines are 30). But, the best thing is, because the stock carrier is a monstrous hunk of an assembly, you do not change the carrier with a Detroit,(its basically a massive lunch box locker). So detroit only cost about $325(and that's if you don't shop around). My disk brake conversion didn't cost over $150 ($40 each for rotors, $40 for loaded calipers, plus about $20 for brake lines. I had about $1000 into my entire 14 build up, including cost of the axle, gears, locker, disc brakes, and new lug nuts. Not bad for a full floater, rear axle with discs, 4.56 gears and a detroit."

Let's have a closer look at the beast

Closer look at the hub (brake disc or drum removed, looking at it from the back [inside]) and wheel bearing / spindle hardware.Note that the spindle threads are the same as for Dana 60 front and rear axles and Dana 70 rear axles. This means all the different styles of spindle nuts (4 slot, 6 slot, hex, rounded hex) and lock washers can all be interchanged.Part numbers for the spindle hardware, courtesy of KWTMECH, from left to right are:

Spindle flat washer: Dorman 618-048, spindle nut: Dorman 615-130, spindle lock washer: Dorman 618-049, spindle nut: Dorman 615-130

Watch out for this when you go to remove the wheel hub outer bearing and race. The bearing does not simply fall out of the end of the hub on most FF axles - its OD keeps it captive. Instead, a snap ring in the hub, accessible from the back of the hub (yellow arrows) needs to be removed so the wheel bearing can come out the back.

Blue arrows show corrosion, indicating requirement for replacement bearings and races.

With the carrier removed, here's a look inside the diff:

1. Threaded carrier preload adjusters
2. 3/8-NC16 diff cover bolt hole (14 in total)Extra (third) pinion support bearingMagnet for attracting and holding metal particles / debris in the gear oilAre where my 14b has been ground down for clearance
3. 3.25" x 1/2" thick axle tubes

Dimensions on the shafts are:Spline Diameter (yellow arrow) 1.59""Neckdown" (green arrow) 1.367"Operating diameter (purple arrow) 1.351"Spline length (blue arrow) 2.165"Spline engagement (red arrow) short side 1.418"Spline engagement (red arrow) long side 1.569"

Then you simply slide the key in the key way and put on the clip ring. The clip ring has a curved end that fits in the spindle groove to securely block the key from backing out. The clip is very thin and flimsy which makes it easy to remove with just a screwdriver and allows it to fit snugly around the spindle in the threads.Part numbers for this style spindle hardware, courtesy of KWTMECH, are:

Hub nut: Dorman 615-132, Key: Dorman 615-140, Clip Ring: Dorman 615-141.

25 - 35 (new bearings)

5-15 (reused bearings)

@ splines 1.54", @ neckdown 1.367", operating diameter 1.351"
@ flange 1.458"

30 splines

SRW
(single rear wheel truck)

C&C
(cab and chasis truck)

Type A SRW / Van 14 bolt hub

Type B C&C / DRW 14 bolt hub

As for all the local and big chain parts stores - they will all gladly sell you a "strap kit" for a "1-ton GM rear axle" or "GM 10.5" rear end" or a "14 bolt full floater" or a "1980 Chevy K30 1 ton 4x4 " or whatever else you have to say to them to get one - but, in my experience (NAPA, Car Quest, Canadian Tire, and a couple of local independents) they are all WRONG, and won't fit at all.

The top strap is the one the parts stores will sell you, the bottom the GM part

The gears machined and re-installed

Just over 2" of clearance was gained. That's the same (at the diff) as going from 35" to 39" tires!!

Originally, Phil made a quick cover by altering a stock cover. It didn't last well enough for his liking, so in the end he constructed a complete custom cover from 3/8" plate steel, which has reportedly held up very well. Unfortunately, I have no pictures of the later cover, but here are some of the original.

EDM is one of the most accurate manufacturing processes available for creating complex or simple shapes and geometries. EDM works by eroding material in the path of electrical discharges that form an arc between an electrode tool and the work piece.  EDM manufacturing is quite affordable and a very desirable manufacturing process when low counts or high accuracy is required.  Turn around time can be fast and depends on manufacturer back log.

The EDM system consists of a shaped tool, an electrode, and the part. The part is connected to a power supply. To create a potential difference between the work piece and tool, the work piece is immersed in a dielectric (electrically nonconducting) fluid which is circulated to flush away debris.The cutting pattern is usually CNC controlled.  Many EDM machine electrodes can rotate about two-three axis allowing for cutting of internal cavities. This makes EDM a highly capable manufacturing process.EDM comes in two basic types: wire and probe (sinker). Wire EDM is used primarily for shapes cut out of a flat sheet or plate. With a wire EDM machine, if a hole needs to be created, an initial hole must first be drilled in the material. Then the wire can be fed through the hole to complete the machining. Sinker (probe) EDMs are generally used for complex geometries where "line of sight" is not thru/straight or very small pieces where conventional milling is not practical or very difficult due to the hardness of the material-such as cast and heat treated tooling. Probe EDM can cut a hole into the part without having a hole pre-drilled for the electrode.Design Considerations

• Relax the surface-finish for the part, if feasible. This allows the manufacturer to produce the part with fewer passes, at a higher current level and a higher metal-removal rate. Design the part such that the amount of stock removed by EDM is relatively small. Use traditional machining techniques to remove the bulk of the stock with the finishing operations performed by EDM. This significantly reduces the amount of time and cost for each part. The EDM manufacturer should consider fixturing such that several parts can be stacked and machined simultaneously or a single part can have several EDM operations performed simultaneously.
• When existing holes are to be enlarged or reshaped by EDM, through holes are preferred to blind holes as they permit easier flow of dielectric fluid past the area being machined

Dimensional Accuracy (+/- 0.0005 inches per inch)
Feature Profile accuracy of .0003 is obtainable with cutting path
Features to feature true position of .002 is reasonable and down to .001 is possible when geometry requires removal and reattachment of wire.

Surface Finish (microinches) Features created by EDM have an "orange peal" appearance.
32 RMS is achievable, 64 or higher RMS is typical.Wall Thickness
Min Wall Thickness (inches): 0.01 (over a 5" inch span)

Depth
Significant depths can be obtained with wire EDM, probe EDM does have depth and access limitations dependant on machine capabilities.  Consult with EDM manufacturer for specifics.