Torsen front axle problems ! anyone else ???

[Squatting Dog]

View attachment 15250

It might be a little thicker than 1/4" but not much..

-Greg

 

[PropDr]

To test:
I’d get some vacuum line caps and plugs, remove the lines from the IWE’s , plug all open ends to prevent contamination of the system and run the truck in four wheel drive.
If the snapping continues it is the IWE unit and not the vacuum controls for it.

---------- Post added at 09:57 AM ---------- Previous post was at 09:48 AM ----------

I also would like to get my hands on a failed unit to see what it is that prevents it from fully engaging with vacuum released.

---------- Post added at 10:12 AM ---------- Previous post was at 09:57 AM ----------

By the way, the concept of the unit is the same as is used in a manual transmission to lock a gear to the shaft, it is plenty strong, but it needs to fully engage.

 

[Squatting Dog]

To my knowledge and understanding of how the IWE works the only thing maintaining to the gear is a weak (easily depress with hand) spring that allows the gear to engage the hardened splines on axle shaft. The IWE itself is considered a wear item and the teeth in it are softer to allow it to wear verses the cv shaft. The problem happens when shifting on the fly the teeth of the IWE slip on the cv axle shaft wearing them down and causing them to round an not fully engage the axle splines. (causing clunking under load in 4wd). By eliminating constant engaging and disengaging of the IWE will prevent wearing of the teeth and slipping. In theory...

-Greg

 

[blockdoc]

Or avoiding shifting on the fly should help avoid it too, then.

 

[Squatting Dog]

Yes, it does help.. The issue I am seeing is the additional torque/power provided by the torsen is over powering the IWE spring causing it to slip.. It might be an easy upgrade to a stiffer spring.. I am going to talk to svt enginerds and see what they think this weekend..

-Greg

 

[PropDr]

Or avoiding shifting on the fly should help avoid it too, then.

Good point!
Also, if the IWE ring gear is softer,with the units new, run the truck in 4x4 hard; there will be a minor deformation/imbedding effect that will enhance a positive engagement.

---------- Post added at 10:56 AM ---------- Previous post was at 10:52 AM ----------

If you have to shift on the fly make sure there is no load on the drive train, like shifting momentarily in to neutral.

---------- Post added at 11:06 AM ---------- Previous post was at 10:56 AM ----------

Yes, it does help.. The issue I am seeing is the additional torque/power provided by the torsen is over powering the IWE spring causing it to slip.. It might be an easy upgrade to a stiffer spring.. I am going to talk to svt enginerds and see what they think this weekend..

-Greg

The spring pressure will be limited by the amount of vacuum under all driving conditions.
To supply a constant higher vacuum the system might need a vacuum pump, or a reservoir with check valves to maintain the disengagement during low vacuum situations.

 

[Mike TexaSS]

I have a 2013 raptor and noticed the same clunk while in sand and 4 hi. My truck did it both times I drove hard in sand. Once at 300 miles and again today with 900 miles...wtf. Clunk or pop isn't a normal sound.

I have shifted on the fly. Should I take the truck to the dealership?

 

[Steele16]

Mine does it allll the time. If anyone comes up with a fix put me first on the list.

 

[Mike TexaSS]

Drive it til something really breaks! I like that approach.

 

[Squatting Dog]

I have two candidate hubs now (on my truck)... Will look into a fix when I swap them out!

-Greg