Hi all

Today I got briefly stuck on a winter road with the 2011 XK with new winter tires mounted.

In fact I had to stop in a section of the road where one of the rear wheels was on clean road surface while the other rear wheel was on ice and spinning.

Now obviously this is the effect of the open mechanical diff of the XK. But I had thought that with ESP and all other electronic helpers on board, there was also a system using selective breaking of spinning wheels to simulate a diff lock.

Were such electronic diff lock systems not stock on the XK or actually not available? Or do you have to apply considerable power trough the accelerator and let the wheel spin quite fast, before this helper system kicks in with selective breaking?

br
ter

 

Tap brakes while giving it low to moderate amount of gas, this will allow the wheel with some traction to push you off the ice.

Otherwise with ice, less is better. So always feather the accelerator pedal to not get stuck.

 

Hey Ter at least you got away to make this post!

i sincerely hope I'll not be putting my e-diff and winter tyres to this type of test.

What tyres on the rear and how much tread?

From my old x100 days I always carried a bag of kitty litter in case this type of thing happened, only did it once with winter tyres fitted as well, but that was 10yrs ago.

 

Thanks all

I have brand new Dunlop winter tires on the car. Just fitted two weeks ago.

Thanks for the hint re simultaneously applying the break. Will try that next time when stuck.

My question goes mostly in the direction as to whether the XK X150 range didn’t have any electronic systems available to avoid spinning wheels due to open diff applying the ABS-break on the affected wheel. Such system is explained e.g. here: cartecc.com - Limited Slip Differential (electronic)

I believe such systems are today in 2020 standard on most cars.

Edit:
And also the 2011 XK should have such system included in the Dynamic Stability Control (DSC).
No clue why this didn’t work the other day???

See user manual:







br
ter

 

Did you have Winter Mode switched on?

Button on the left just below the gear selector. This selects second gear for driving off and greatly reduces wheelspin in icy conditions.

Graham

 

Yes, winter mode was on (I turn it on in December and leave it turned on until approx. April).

Because I am not getting any error codes or other error messages, I assume the DSC works.

My only explanation for the system not kicking in the other day, is that I have not applied enough power to the throttle, because to my knowledge these systems usually need certain minimum revolutions of the engine and wheels to kick in.

Unfortunately I do not recall up to how many revolutions I tried to accelerate when I was stuck. However I do believe that most probably I spun the engine up to approx. 1500 RPM.

This hypothesis is further supported by the fact that the yellow “sliding car” symbol was not showing in the dashboard when trying to get going with one wheel spinning. I did see the symbol some minutes later when I intentionally provoked a power slide on a snow covered parking lot.





br
ter

 

I do not know what exactly it does, but there is a low traction mode in my 2009 called DSC TRAC, it will permamently light those orange squigglers when the car is in that mode, but not the text that says active unless active.

I believe the DSC's primary function has to do with angle of car vs angle of motion vs interpretation of driver input.
It helps torque vector the car to bring those three together when it thinks they diverge.

 

Years ago I had my F250 4WD huge tires, air lockers, big lift, etc etc stuck on a totally level, flat and icy driveway. All four tires would spin at the lightest RPM. I had to go get a small pail of sand to get me moving even the slightest. It was quite embarrassing, actually.