Removing the fuse #12 10A is just for a short road test to see if that cures steering woes. Not as a permanent solution. May be wise to choose a mild day to attempt this test. It helped my car, so I found the module in dash right side, cut the power wire to it, & extended the wires in order to install an easy reach manual cut out switch to over ride the function. The problem seems to be around 30 to 35 mph as I recall. You may just unplug that module or temporary disable it some other way. I heard one person say it is possible to have an electronic guru modify the module so it could be tuned for drop out at different speeds. Above my pay grade, sorry. For me I'd like it to drop out around 10 mph. You can feel the road so much better. Not sure how it senses road speed, but one might assume it counts pulses from the speedo circuit. If that circuit could have it's pulses doubled just to the module, that might work to make it kick out sooner? Lowering the set point threshold some way might work too. I'm sure some smart electronic guy can figure this out.

 

Interesting. My 2003 xkr has the same problem. I've changed all the suspension bushes for powerflex plus the front shock top Bush and have noticed only a minimal improvement in how the car feels. Following this discussion and I'm wondering if its the tyres. The car is on 20inch rims with nexen n'fera SU1's. I've run these on my business car and they are average at best. I'm looking around for new tyres but limited in NZ for choice with the 255/35 and 285/30 tyre sizes. Some tyres are not bought in. I'm thinking continental sport contact 5's but that would be $3k for the set. Otherwise can do falken fk510's or Dunlop sport maxx or pirelli P zero's.

 

I'd venture to say it's not the tires. The XK's hunt with any brand I've used even Nexum and Pirelli's. A lot of cars are aligned with the Castor set different from side to side. These cars are set up for ultra quick ultra light steering that can be unnerving at steady state cruise. I suggest having your alignment specialists disregard the OEM specs and adjust the Castor to slow down the steering effect only on the side that needs it. In other words, move all the upper control arm shims to the front to increase the CASTOR. One side is already done this way. The factory did it that way to compensate for the road crown which varies a lot. I did mine years ago when I did the shock tower bushings and love it. Only like .030" or so, but what a difference that makes. .Has zero effect on my tire wear, but twice as stable. Seems to corner even better since both front tires have the same camber.

 

It is US spec that says different castor angles. Mine, that lives in Norway, has the (almost) same castor angle at both sides. Not at maximum, but only 1 shim left at the front upper bushing. I am not sure if that is a thin or thick shim, but it will only make 0.2 or 0.4 degree change at the castor angle. It is now 6.55 left and 6.85 right

 

I had this problem and it turned out to be a tie rod end. I noticed it right after I replaced the upper shock mounts and shocks and upper wishbone bushings. At first I thought I must have gotten the castor shims in incorrectly, but on close inspection I found a slight play fore and aft in the right hub. I think now that I may have stressed the tie rod end a bit when doing the
other work. In any event, it was 15 years old and a relatively cheap fix.