12 months, 12,152 miles, who says an XJS is unreliable?

Friday was the day that I took J258 for its MOT re-test, after it failed the day before for a minor handbrake imbalance and a loose seat belt anchor, which had been loosened slightly to make it easier to adjust the handbrake, somewhat ironically. Anyone who has used or worked on an XJS hand brake knows that they are utterly useless. They are poorly designed and rarely release as they should, and I wouldn’t often trust one to hold the car (as is often the way with a great deal of classics). The one fitted to J258 has always worked well though, with none of the sticking or balancing that is required of some XJS. The subsequent pass with no issues was a did little to ease my irritation at the failure the day before. The car really does want for nothing in mechanical terms, and in my eyes it shouldn’t really have failed. In recent weeks we’ve inspected and prepared the car, and perhaps moved a few jobs forward to try and ensure there were no issues.

Against any XJS that I’ve driven, J258 has always driven beautifully, which is one of the reasons I’ve always loved it. True, it may not be a V12 but I like the 4.0 AJ6 well enough for that to be a non-issue. Over the past thousand or so miles I’ve noticed the rear end of the car becoming more active, and I suspected that the shock absorbers may be past their best. This was confirmed upon inspection as they’d just started to mist, which would have been an advisory for MOT. Given that, and that the roads near where I live are sadly nothing like billiard table smooth, I decided a new set of shocks (and springs) for the rear end were in order. We were already having to replace the handbrake pads and so it became a chance to lower the rear subframe and check it all out, too. On speaking to the pleasant people at SNG Barratt (it’s always better to phone them, they’re on the ball and are helpful), it emerged that my car was a sport pack car – which explains why it has always sat so nicely. It isn’t possible to get OEM shocks and springs any more, but a set of mildly adjustable GAZ shocks and a set 25mm lower (which should hopefully match the old ones) Eibach springs set me back less than I’d thought they would after a discount was applied. The differential was also leaking, a common occurrence on an XJS as the inboard brake set up and the heat which is generated.

Shortly after removing the rear subframe, and then the rear shocks and springs, we discovered that four new differential bearings were also needed, which delayed the reassembly (although, again, SNG did a great job and got the parts out to me for the next working day). No other issues were found, fortunately, and the rear end went back together smoothly. The rest of the list was minimal and included small jobs such as the horn not working, which was simply a small wiring issue.

Early on this year I’d set myself the challenge of covering over 1,000 miles a month in the Jag, so over 12,000 miles for the full year between MOT tests. I use the car daily, and during lockdown I moved house, meaning that my commute grew from 6 miles daily, to 62 miles daily, which could only help with the challenge. With that move the car drove better and the fuel economy improved too (although not to the extent that replacing the O2 sensor did). Although it wasn’t really a particularly hard challenge to complete, it still pleased me to realise that I’d succeeded in completing it, and I doubt there are many people covering more miles per year in an XJS at this point, despite them being very useable as a daily driver.

In the last 12 months J258 has never broken down, never failed to start, and never really given me any issues. Of all the cars I own it is quite possibly the least troublesome and most reliable. Classic cars, like any car, are best when they’re used. You can, of course, cause problems by overuse, but generally using an older car weekly or at least bi-monthly is a good thing, and has the potential to keep costs down. All of the work completed on the Jag this year is commensurate with its age and mileage. The fact that it is a high mileage car is a great thing, and hitting mileage targets is one of those small and silly pleasures that probably mean more than they should. A classic car is a large expenditure, and using it often only means you get more for your money. Using one daily makes it no less special than one used on sunny weekends, and they become something of an old friend and less of a chore to use.

Over the past 12 months I’ve averaged 21.1mpg, although I expect that average to continue to rise given that the O2 sensor was changed half way through the year. My best fuel economy was 31.2mpg, which I was quite impressed with for a near 30 year old, large engined and high mileage car. I think it could possibly do even better than that too, but I’m not too worried. On motorway journeys a range of 400 miles is easily obtainable, which is an important quality in a GT car for some.

With this little challenge complete, I’m now trying to come up with a new, car based challenge, and perhaps one that is a little more adventurous. If anyone has any ideas or suggestions, I’d love to hear them.

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