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I've just bought my first XK8 and the back tyres will need replacing soon. They currently have ContiSport 255/45 ZR 18 99W. They seem to drive fine but are these the best tyres for the car? I'm after low noise, grip and good wear......the perfect tyre!! Any suggestions? Anyone know the best place to buy tyres in South West London?

Hi & welcome to the bulletin board.
You might get some helpful answers to your queries by using the search facility to examine previous threads on this topic. However, a brief summary might go something like this. Jaguar spent a lot of development time ensuring that the original equipment Pirelli tyres gave the optimum compromises between noise, grip and longevity. Nevertheless, development doesn't stand still and some would now argue that Dunlops (later supplied by Jaguar on many new cars) provide a better set of compromises. The key message is not to compromise safety either by fitting lower spec tyres or tyres from possibly dubious far eastern manufacturers. A further tip is to avoid mixing brands on front and rear axles because some some combinations can produce odd handling characteristics. It's as well to plan ahead for new tyres as, with the multiplicity of modern tyre sizes, stocks of any specific tyre size are often low which can limit choice. Mike.

Sorry to contradict you Mike

My 02 4.0 Spec XK8 has the following tyres specified in the Vehicle Care Book

Front - Continental ContiSportContact 245/45 ZR 18 96W
Rear - Continental ContiSportContact 255/45 ZR 18 99W

I have used Pirelli P Zero's & ContiSportContact 2 & 3 on my XK & found that the Conti's last longer, are quieter & the dreaded Traction Control does not kick in as much

Allan

Sounds like I should stick with the Contisports. Looking through other threads, people have preferences for other brands but given that I only need to replace the rears (the fronts have 6-7 mil and are contisports too) it would seem inadvisable to mix the brands. Many thanks for the advice. The ride on the car is absolutely fine as it is but I have only been the proud owner of an XK8 for four days so have no relative experience of how the car should feel.

By way of an upate, I ended up putting Pirelli P Zeros' on them (found an offer for two fitted @ £400) and have no regrets.

Also, I have had various problems with my driver side window failing to respond to the switch. I usually resolved it by diconnecting/reconnecting the battery, however, I have now replace the battery and hey presto......no more electrical problems. Seems obvious but my old battery showed no signs of draining according to the meter but now that the new battery has been fitted, all is well! Cost me £140 for a Bosch but for peace of mind and a 5 year guarentee, its well worth it.

Although annoying when they happen, nine out of ten erratic electrical glitches on these cars are solved by battery replacement. Many of the electronic control units on XK8s and other Jaguars require minimum voltages to operate. What can happen is that what appears to be a perfectly serviceable battery may drop its voltage momentarily below the required threshold voltage of a control unit when the battery is placed under a heavy load, eg cranking the engine. Then, the affected component either turns on a warning light or loses its memory settings. Mike.

Thanks Mike,

Have to say that I am far more comfortable heading into winter with a new battery. Feels like the car runs better too although I suspect this is wishful thinking! It would appear that the problem mainly arose when the cruise contol was switched on and only the drivers side window was affected?? Locked in the up position! I guess a 14 year old car is likely to have its own electrical foibles!


Will be getting the car serviced early next year. Does it require tuning or should a major service deal with this?

Many thanks once again.

John

Hi John,

My advice would be to find a good Jaguar specialist equipped with either Jaguar's own diagnostic system or the Autologic system (with Jaguar modules). Then, when you have the car serviced, it can also be scanned for fault codes. The only 'tuning' necessary is to ensure that the car's emissions performance is within specification so that it will pass an MoT. The lambda sensors in the exhaust of all modern petrol cars deteriorate with age. This deterioration gradually reduces engine performance whilst slowly increasing fuel consumption so, apart from logging fuel consumption, periodic emissions' checks are the way (the best way) to keep an eye on them and to understand when their performance is tailing off. Mike.

A question for Mike H.

Is their a typical life expectancy for a Lambda sensor? Last MOT my V8 produced the expected readings and the car passed ok. The reaction times for the sensors feeding back to the upgraded ecu were according to Dave Marks at the Diagnostic Seminar, the most reactive of any he had seen on the diagnostic equipment he was operating. Hopefully that will continue to be the case for a while yet. Would I expect a tail off with sensors that have covered 75k miles or should I begin to think about replacement?

Mike K

Hi Mike,
Not so long ago I would have suggested that lambda sensors only have a life of around 50k before showing signs of deterioration. However, the good news is that Jaguar appears either to have upgraded the quality of the OE equipment items or that the better mixture control exercised by the improved injection systems of the past few years gives the sensors an easier life. Hence, today it's more difficult to be definitive about sensor lives but Jaguar's later V8s seem to be able to go further than the earlier versions before replacements are needed. Mike.

Could anyone recommend a good independent Jag dealership close to Kingston upon Thames?

Hi Mike,
Not so long ago I would have suggested that lambda sensors only have a life of around 50k before showing signs of deterioration. However, the good news is that Jaguar appears either to have upgraded the quality of the OE equipment items or that the better mixture control exercised by the improved injection systems of the past few years gives the sensors an easier life. Hence, today it's more difficult to be definitive about sensor lives but Jaguar's later V8s seem to be able to go further than the earlier versions before replacements are needed. Mike.

Hi Mike ,
Agree with you on this one , my car has just passed it's MOT with flying colours , the tester did remark that the emissions were well within range and pretty well exactly the same as last year , not bad for a car that's covered over 131,000 miles and still on it's original Lambda sensors and cats , recently got an average of slightly over 30 to the gallon on a run to Bournemouth and back according to the not so accurate in flight computer

All the very best ,

Nik

Hi Nik,

I think you're doing the best thing possible for all round car health - you're driving it! Given sensible maintenance (especially the gearbox), these cars don't have problems covering high miles. It's low mileages, short journeys and general lack of use that cause most problems. Mike.