Qdii

[xkcommander]

I know that this does almost as good a job as a traditional locker locking up the diffs when under power but what happens down hill? A traditional locker will provide additional traction on a steep decent. Will QDII lock up if it detects slip when not under power??

cheers

[SAL-XK]

Yes it will although the parameters the computer uses to unlock is debatable.

[Ahmed]

Not sure ,, but what I know that the QD-II clutches disengage once break is applied ,, so if on steep down hill and using break to control the speed then I don't think the clutches will lockup!

[jeep5253]

Originally Posted by xkcommander

I know that this does almost as good a job as a traditional locker locking up the diffs when under power but what happens down hill? A traditional locker will provide additional traction on a steep decent. Will QDII lock up if it detects slip when not under power??
cheers

The short answer is no. However, the 2008 and up models have Hill Descent Control and Hill Ascent Control.

[SAL-XK]

Ahmad I have to disagree whith your answer ive seen plenty of XK's hit the brakes while on obstacles but there axles remained locked. I should say this is all based on being in 4LO.

Edit: Sorry misread that question I thought it said will the axle stay locked going down hill.

[xkcommander]

As I seem to have not been completely clear the question is:

When you are undertaking a steep descent under engine breaking in 4 Lo will the QDII detect loss of traction and lock up thus giving the same assistance that a traditional locker would. For example when there is complete loss of traction (in the air) by one wheel.

If the answer is no then:

a) Is it possible to retrofit hill descent control on a 2006 model or
b) I remember someone was playing around with the idea of forcing the axles to lock with a switch. Does anyone know what happened with this effort?

thanks

[SAL-XK]

The computer is pretty complicated.

1. In 4LO if you started down hill already locked it would stay locked for some time.
2. In 4LO the axle is pretty much Locked or a heart beat away from locking. In 4LO I've never really seen one tire take off and then the system locking its really sensitive in 4LO very little wheel spin before it takes over. Now in AWD yes you'll get that wheel spin then the computer will fix it.
3. You don't need hill decent just do it you self 4LO 1st gear and add some brakes when needed not locking the wheels into a slide.
4. Hills steep enough to worry about traction you need to be riding the brakes anyway so the axle being locked really don't matter. Most the hills I consider steep the engine even in 4LO 1st gear won't hold a slow enough speed I need to work the brakes unless it's all smooth then who cares right LOL