Virginia 4x4's Dana 44 knuckle machining write-up

[Virginia 4x4]

Flat Top Knuckle Machining Service

This tech write-up is meant to shed some light on what we do after you ship us your Dana 44 flat top knuckle for machining.

The problem: passenger side knuckles are not machined from the factory because steering linkage typically bolts to the drivers side knuckle in a factory setup. However, in a lifted vehicle it is desirable to have a crossover steering setup because it will flex more than a factory setup and without effecting steering as much.

The solution: In order to run the steering draglink from one side to the other you will need to bolt a steering arm to your pass side knuckle. The knuckle is cast so it is imperfect on the top, it must be machined flat and holes drilled and tapped.

Passenger side knuckles already have bosses in the correct location so drilling and tapping will not weaken the knuckle… its almost like Detroit was anticipating that we would be doing this 30+ years later…




Step 1:
Unpack and inspect the knuckle.

First we unpack your knuckle. They ship very well in a $10 flat rate box from the USPS. We inspect the entire knuckle but specifically the weak points where they are known to crack. We can also perform dye penetrant inspection for additional cost. This is a non-destructive way of checking for cracks that involves a several step cleaning and dying process followed by a visual inspection with a special light. Personally I think this is overkill but if you need peace of mind that your knuckle is 100% unbroken then this is the way to do it.




Step 2:
Setup and indicate the face:

Before bolting down and machining the top flat we indicate the face. This ensures that your holes are drilled in the right place. This particular knuckle was boogered up so we had to file the face a little so our indicator would run true. Once the dial reads zero from front to back we clamp down the knuckle and check it one last time to make sure nothing moved when tightening down our clamps.
Sometimes we have to stone the bottom surface so it will sit flat on the mill. This is not uncommon.




Step 3:
Machining the knuckle top:

This is pretty self explanatory. You can see the chips flying off the knuckle in the picture. We use a carbide insert cutter and take several very light cuts. There are several reasons for this; we do not want to take too much material off. Several light cuts lets us creep up on our goal of 95% -99% cleanup. Anything over 100% is just weakening your knuckle. Taking lighter cuts also ensures a quality finish by reducing chatter… the carbide tooling helps ensure a quality finish as well.








Step 4:
Indicate the bore:

Indicating the face ensures that we have our knuckle straight with the y axis but we need another point of reference before we can begin drilling and tapping holes. The bore of the ball joint boss is used as the reference point. We place the indicator in the center of the spindle and turn the spindle by hand, moving the table until the dial reads zero when spun all the way around the bore.




Step 5:
Drill and tap:

ALMOST DONE! Now we drill each hole mirrored exactly from the factory drivers side. We drill and tap (AKA threading) 9/16-18 fine thread (same as stock). Our machinists insist on sharp taps for this operation but we run studs down in each hole anyway to make sure all the threads are in good shape.



Note:
Some customers request 5/8 threads which is not a problem but again we believe this is overkill as we have never actually seen 9/16” studs (or bolts for that matter) sheared off. Keep in mind if you do go with the larger studs more material will be removed from your casting which may weaken the knuckle. You will also have to drill your arms to the larger diameter as well.

Here is the knuckle before deburring and final inspection:

[Virginia 4x4]

Just posted up the draglink/tierod kit that goes perfect with this, or any front axle.

[ohiozj]

cool. nice to see that process in action.

[ohiozj]

am i missing a price? i checked and dont see it anywhere.

i have a friend that needs a set of d44 knuckles done soon.

[Virginia 4x4]

Originally Posted by ohiozj

am i missing a price? i checked and dont see it anywhere.

i have a friend that needs a set of d44 knuckles done soon.

this thread is just a write up if you go here you will see a price in the vendors market place