Hemi395
Senior Member
- Joined
- Mar 18, 2013
- Posts
- 8,989
- Reaction score
- 15,672
- Location
- Cape Cod MA
- Ram Year
- 2013
- Engine
- 5.7 Hemi
They made some changes to the 44-44 in 2017 although no one is really sure what changes...
Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.
They made some changes to the 44-44 in 2017 although no one is really sure what changes...
Great find!!Hmm, interesting.
Wonder if that has something to do with vibration getting worse in 4-Auto and if '17 is the year they started with "some" engagement even without any rear wheel spin.
Any idea why this xfer case is so secretive?
EDIT: found a list of itnernal parts vs years. Parts used only in 2016-2017 (and presumably 2018, but the list was published in 2017) were the transfer case shift fork and the Mode Hub (magnet housing). Everything else was in use from 2011 to present.
@Ken226 The list also has the specs on the clutch pack shims, not sure if this helps compare to a shim set from 44-45: https://marketing.transtar1.com/acton/attachment/18758/f-147c/1/-/-/-/-/BW4444 Flyer 0917.pdf
I never said the clutch pack disengages while the wheels were turned, the clutch pressure is decreased. It will still be transferring torque but it won't have the same clamping force that way it can eliminate the crab walk that happens when you drive a truck with a real 4wd system on dry pavement.I've been doing research on these cases looking for parts interchangeability and keep seeing the NP-246 and NV-246 referenced on GM sites as interchangeable. Also seeing lots of stuff on Mopar sites indicating that the NV-246 and the BW 44-44 are somewhat interchangeable.
If that's the case, or if at least if they share the same clutch plates, there are some quality aftermarket clutch plates available for the NP246 and NV246.
If they use the same clutch plates, installing high quality aftermarket clutch plates would probably do wonders for those having trouble.
https://www.ebay.com/itm/Transfer-C...ash=item1ec000a1f9:g:F14AAOSw9GhYgYYk&vxp=mtr
It seems to have the correct number of plates. I seem to recall from a photo from Rockland Gears website counting 9 steel and 10 friction plates in the 44-44 they disassembled.
quite a bit of info in this thread:
http://www.ramforumz.com/showthread.php?t=217104
This video is of a well functioning 44-44 equipped truck. At the 2 minute 20 second point, while in 4 auto and all 4 wheels spinning, he turns the steering wheel all the way to the left. You can clearly see that the front wheels continue to spin, at every point as he turns the steering wheel. In his properly functioning 44-44, turning the steering wheel does not disengage the 44-44 clutch pack.
At just after the 7 minute point they do a trailer test on ice, in 2wd, 4 auto and in 4 lock.
At some points in the video, its impossible to see what the opposite side wheels are doing, and it doesn't indicate which mode the transfer case selector is in. But in the sections where you can both see all the wheels, and it indicates the position of the transfer case selector, you can see how it works.
Keep in mind that Ram trucks use Brake Traction Control. So, if the front left starts spinning, the traction control will brake that wheel and transfer power to the right, and vise versa, and the same on the rear wheels. So at many points in the video, you will see the front wheel only spinning, which means the opposite front is braking. Also, if in a 4wd mode, you see the rear only spinning, then look at the opposite front and youll see its spinning as well due to the Brake Traction Control, which occurs at the 3min8second point with the right rear, and front left spinning. Then again in reverse, at the 3min40second point, with the front right and left rear spinning.
At the 4 minute point you can see a good example of the brake traction control switching back and forth braking on both axles searching for a wheel with traction, with at first, the right rear and front left spinning for a few seconds, the switching to allow both right side wheels to spin.
The trailer test at the 7 minute point is the best example, as your able to see at least 3 of the wheels AND theres a caption showing which transfer case mode is selected.
It comes with a 48-11 not 44-11, says stronger but not much other infoThe 44-11 is a an electromagnetic ball ramp, torque on demand system. It's been used by Ford on the Explorer for quite some time.
Internally it looks very similar to the 44-44. To be honest, it appears to be a slightly lighter duty case than the 44-44, similar to the 44-05. I could be mistaken about that though. Rockland gear has some info on it on their site.
While I do understand Lovesracing1988’s position, in that someone he knows, trusts and believes told him it was designed to slip under certain circumstances, it isn't reasonable for me to expect him to believe me (some random guy) over his friend.
I can only attest to the parts I observe to be present inside the transfer case, how how they interact with the other parts.
This is a drastic oversimplification, but try and visualise the inside of the transfer case as having 2 rotating plates facing each other separated by s tiny gap.
The front plate (we will call it the driven plate)is connected through the front driveshaft, to the front differential and front wheels.
The rear plate is connected to the transmission and rear wheels via the transmission output shaft (we will call the rear plate the drive plate).
Visualize the drive plate (rear plate) as bring on a splined shaft which allows it to slide fore/aft, just enough that it can can be forced forward along the splined shaft, and into contact with the front shaft.
For this explanation, it's necessary to visualize relative clock positions of the two plates (the plates clock positions relative to each other). Let's say that when driving in a strait line, on pavement, the rear wheels are turning and pushing the truck along the highway at x speed. The roadway is causing the front wheels to rotate at the same speed as the rear wheels, as such, the two plates are rotating at the same speed relative to each other. They are maintaining the same relative clock positions.
The ballramp/torsion spring assembly is basically a big, heavy duty ratchet. Like a recluse motorcycle clutch. Imagine it as being similar to a starter Bendix as well. Picture the drive plates shaft as having helical splines, Wich the drive plate rides on. Like a nut on a screw. When the shaft the drive plate rides on is turned, the torque applied to the shaft forces the drive plate tighter against the driven plate. The higher the force applied to the shaft, the higher the force the drive plate applies to the driven plate.
If the truck begins to turn, the front wheels begin to track around a larger radius than the rear wheels. This takes the pressure off the drive plate and allows the driven plate to turn faster than the drive plate. This could be viewed as "slip", but not the kind of slip that causes wear. It's more like the slip that a brake pad undergoes, when the brakes are-not in use.
When the rear wheels start to lose traction, this allows the drive plate and shaft to advance it's clock position relative to the driven plate, which, because of the drive plates helical splines, forces the drive plate against the driven plate and rotates the driven plate as well.
The torsion spring is the part that holds the drive plate and the driven plate apart.
The electromagnetic clutch , when energized, overcomes the strength of the torsion spring and forces the plates together.
So, in 2wd, the electromagnetic clutch is never activated and the drive/driven plates are never in contact.
In 4 auto, when the computer detects wheel slip, it energizes the electromagnetic clutch, it overcomes the force of the torsion spring forcing the plates together. When the plates are in contact with each other, the ball ramp (helical splined shaft) forces the plates together using whatever amount of torque the engine is producing. If you start to go around a turn, the driven shafts clock position advances relative to the drive shaft and the ball ramp releases, allowing the torsion spring to separate the plates. If your rear wheels slip while in the turn, the drive plates clock position advances relative to the driven plate, and the ball ramp mashes the plates back together. About 90ish degrees of advance in the drive plates clock position, relative to the driven plate, is required to force the plates together. When the computer senses no more slip, it deactivates the electromagnetic clutch, allowing the torsion spring to separate the plates.
It is important to note however, that the engines torque transmitted through the helically splined shaft and drive plate, greatly exceed the strength of the torsion spring. If under engine load, computer deenergization of the electromagnetic clutch will not cause the drive plate to release the driven plate.
In 4 lock, the electromagnetic clutch remains energized. The clutch plates remain in contact. Any time the driven plates clock position advances relative to the drive plate, such as while turning, the ball ramp (like a ratchet) allows the driven plate to advance it's clock position relative to the drive plate. Any time the drive plates shaft (helical splined shaft) attempts to advance it's clock position relative to the driven plate, it forces the plates tightly together.
In 4lock, while turning, the driven plate is advancing it's clock position relative to the drive plate, so technically, it is in fact slipping. But, it's slipping only a few degrees and only overcoming the applied force of the electromagnet clutch, which at 12volts10amps, is very small. The only force capable of any significant effect is the engine torque, via the helically splined shaft, forcing the plates together.
Now, all that said, it is a simplification for the purpose of easing explanation. There is no helically splined shaft. A big heavy duty assembly of balls and ramps takes the role of the helically splined shaft.
The 2 clutch plates are actually a couple dozen plates mounted in a big splined basket.
The clutch basket assembly is rated for about 1700 ft lbs of CONTINUOUS use, and for intermittent loads of much much more. Any slippage occurring as the driven plates advance clock position relative to the drive plates do-not occur under load.
Any time the drive plates attempt to advance clock position relative to the driven plates, there is significant load. The engines torque force the plates together. The more throttle you add, the more the torque, the more the force driving the plates together.
If your in 4 lock or 4 auto, and the transfer case clutch pack is allowing the rears to turn but not the front, then there is something severely wrong.