Upgraded IWE

[Squatting Dog]

True statement Greg. You mention above the vacuum not building fast enough to disengage the IWE fully when using the Remote Start, why would that be any different then jumping in the truck starting and leaving immediately? I would think it would be an issue no matter which way you start your vehicle. Hell, I hardly ever wait 2 minutes before I put it in gear.

It wouldn't, I was under the assumption that the IWE solenoid operated during remote start. This would allow more than enough time for sufficient vacuum to build. Since the IWE solenoid is not powered until key on, this would contribute to some of the issue. I know I remote start my truck and jump in and take off almost everyday in winter. Which would explain some of the damage to "new IWE" (never turned on 4wd).

-Greg (aka Squatting Dog)

 

[Wilson]

+1^

 

[Squatting Dog]

I can't get mine to last 1% of those miles. I'm starting to think it's me, lol... truck is back in for 4x4 clicking noise. And I was really trying to be careful this time! New tires and 2 wheel drive when I could. Shifted in and out of 4 when at a stop. Slow rolled it before putting any force on it to ensure it was engaged.

Just called the dealer, no word yet. Waiting on call back.

Yukon Joe
www.RUNRAPTORRUN.com

Joe it is not you... Your issue is just like mine and others.. Torsen torque multiplication just eats IWE. The service life numbers were for pre-torsen vehicles (which I got those numbers from Borg warner).

As far as Borg Warner is concerned there is no issue because we keep buying replacement IWE and Ford keeps using them.

-Greg (aka Squatting Dog)

 

[Wilson]

can this be fixed on trail? if not it's a big problem

 

[Stepside]

Is that figuring the torque multiplication of the torsen of 2.52:1?

-Greg (aka Squatting Dog)

Not sure where you are getting the 2.52:1
unless you referring to TBR or torque bias ratio
which is not an increase in available torque,
but a multiplication factor or ratio of what the left & right axle is doing.
Like 20% one side and 80% other side is a ratio of 4 to 1.
I do not know the TBR spec on the Torsen for the Raptor.

 

[Squatting Dog]

can this be fixed on trail? if not it's a big problem

Not easily. At TRR possibly, at Snoball probably not.

Replacement on the trail would require the following steps.

Hard stable surface to raise the offending wheel off the ground, jack and jack stands.

Raise vehicle high enough to place jack stand under front frame. Move jack to lower control arm.

Remove wheel and tire

Take brake caliper off and hang out of the way to not destroy abs sensor or brake lines

Remove dust cover from center of hub and axle nut.

Remove sway bar lower link bolt from lower control arm.

Remove and pop lower ball joint from lower control arm.

Pull/push hub assembly until the axle comes out of hub. Being careful not to screw up needle bearings.

Now you can remove the 3 bolts from IWE and two vacuum lines. Every single one of mine required some motivation to get the IWE off the hub.
Clean the needle bearing because metal shaving from IWE will find it way in there.. Regrease the needle bearing.

Install new IWE, reconnect vacuum lines.

Add some grease to the axle end to replace the grease in the needle bearings that will be pushed out when you are fighting the axle back into the hub.

Reconnect the lower ball joint using the jack to raise the lower control arm.

Reinstall sway bar link.

Install axle but and dust cover

Install brake caliper

Install wheel and tire

Safely lower the vehicle..

That is the basic procedure in a but shell.. When I change mine out again, I will make a better step by step with pictures. Hopefully with RCV IWE upgrade...

I guess it would come down to how prepared you and your group to change these out and the conditions.

-Greg (aka Squatting Dog)

---------- Post added at 06:30 PM ---------- Previous post was at 06:26 PM ----------

Not sure where you are getting the 2.52:1
unless you referring to TBR or torque bias ratio
which is not an increase in available torque,
but a multiplication factor or ratio of what the left & right axle is doing.
Like 20% one side and 80% other side is a ratio of 4 to 1.
I do not know the TBR spec on the Torsen for the Raptor.

Torsen is a Torque Multiplying type of diff with a multiplication ratio of around 5:1. What this means is that whatever torque can be sent to the wheel with the least traction, it can send up to 5 times that torque to the wheel with the most traction. Its biggest advantage is that it can do this extremely quickly and doesn't ever lockup the ratio; continuously "sensing" and adjusting the torque between the two wheels. Its only real disadvantage is that when one wheel has no torque available (say it spinning in mud), then 5 times nothing is still no torque to the other wheel, so you can get stuck just like a std diff. Once the car is moving however this cannot happen.

-Greg (aka Squatting Dog)

 

[PropDr]

I have been following this discussion for some time.
Like Greg pointed out, torque multiplication is a multiplier of the wheel with the lower traction; but it can go only up to 100% of available torque.
If both wheels have perfect traction, both have 100%
The IWE connects the same way as a locking ring in an manual transmission.
It looks to me the problem is a consistent positive engagement.
I remember that in manual transmissions, that had a problem staying in gear after adding HP, we would reshape the teeth so that under power they would pull themselves engaged.

 

[Stepside]

^^^ Exactly - it can only go up to 100%.
Torque Bias Ratio is being confused with an increase over what is available.
The TBR spec is different for what the buyer demands
and I do not know what Ford engineers spec'ed out for the Raptor.
That is done with the way the gears are cut.

The new Torsen differentials have eliminated the "one wheel in the air" problem
T-2R - But, that is another subject and the IWE still sucks.

 

[Squatting Dog]

^^^ Exactly - it can only go up to 100%.
Torque Bias Ratio is being confused with an increase over what is available.
The TBR spec is different for what the buyer demands
and I do not know what Ford engineers spec'ed out for the Raptor.
That is done with the way the gears are cut.

The new Torsen differentials have eliminated the "one wheel in the air" problem
T-2R - But, that is another subject and the IWE still sucks.

Torsen is great but not in this application. On my own Raptor during snowball last year. The slipping conditions caused such a torque transfer back and forth between the IWE that they litterly cleaned the teeth off of them. Going from spinning and catching traction will cause the Raptor to claw through anything. But at the same time constant torque ping pong the torsen creates with the weak IWE is prone to higher rate of failure.
That is why 2012 and up torsen equipped Raptors failure rate is a tenth of non torsen Raptors. (Avg 5000 miles verses avg 50k miles)


T2-r would be a waste in a Raptor because the traction control with independent wheel braking works just as good without clutch pack wear.

Stepside and Propdr thank you for you contribution, I can visualize what is happen but can't articulate it in a BigJ way..


-Greg (aka Squatting Dog)

 

[PropDr]

Quaife!