The Jaguar XJ X351 has become a great-value used car in its older age. Here’s how to buy a great example
We’ve spoken to numerous independent Jaguar specialists to compile this guide and outline some of the common problems that have come to light. But remember, none of this is to put you off buying, merely to arm you with knowledge.
A good starting point for deciding which XJ to own is whether you want the extra 12.5cm in length (added to the wheelbase) – the difference between the short and long wheelbase models. It’s also worth noting the overall dimensions of these cars because they are large, with the SWB measuring 5.13m from front-to-back, although it’s the width that will mean such a car is a tight squeeze on many owners’ driveways and inside single garages. With the mirrors extended, the car is 2.11m wide. Plus, it’s quite a heavy car, weighing in at between 1,775kg and 1,880kg (and a lot more for the special armour-plated LWB XJ Sentinel, as used by several UK prime ministers).
The range of engines for the XJ X351 is relatively straightforward to get to grips with. At the start of production, it was powered by either a 3.0-litre V6 twin-turbocharged diesel engine or a 5.0-litre V8 naturally aspirated petrol. By the spring of 2013, the petrol V8 was supercharged for the XJR model, which produced 542bhp, followed six months later by a supercharged 3.0-litre V6 petrol engine. Power outputs can vary between models and years, but there are, essentially, three different engines for the XJ X351.
If performance is the deciding factor, then none of the XJ range should disappoint. The turbocharged diesel models take around six seconds to accelerate from stationary to 60mph can return around 30mpg in town and almost 50mpg on a long journey. The supercharged 5.0-litre XJR should hit 60mph from standing in only 4.4 seconds, but don’t expect much more than 25mpg. The V6 supercharged petrol sits somewhere in the middle, with a 0-60mph time of a little under six seconds and fuel consumption around 30mpg.
It helps to understand the range of models of the XJ X351, which starts with the Autobiography, Luxury and Portfolio, followed by the Premium Luxury, R-Sport, XJR, Supersport and Ultimate, not to mention the 50th anniversary XJ50. Specifications often vary within these models, depending on which optional extras were chosen, but remember that many features are standard, such as heated front seats, parking and reversing sensors, heated door mirrors, an electronic opening bootlid and a heat-reflective panoramic glass roof. Plus, the LWB models are equipped with four-zone climate control.
Potentially desirable optional extras to look for include electrically reclining and massaging rear seats, introduced from summer 2011. Sports and speed packs were introduced in 2012, which include exterior upgrades, such as gloss-black trim, a front splitter, painted brake calipers and 20in Venom alloy wheels. Some of these packs are model specific, such as the speed pack for the supercharged XJR, which raises the limited top speed from 155mph to 174mph, should you need it.
If you are keen on your in-car entertainment systems, then choose wisely to find a bargain packed with extras. For instance, some centre console-mounted screens are dual view, enabling the driver to use it as a sat-nav and the front seat passenger to watch a film. The entry-level stereo system is a 250-watt head unit with a front slot for a CD or DVD, whereas the Meridian 825-watt surround sound system with 20 speakers is the one to have if you like your music.
Bodywork
With aluminium bodywork manufactured from 50 percent recycled sources, perhaps the days of rusty-looking Jaguars are long gone. However, the bodywork can be complex to repair because many panels are glued and riveted together, so be cautious with any XJ X351 that has accident damage that goes beyond its bumpers.
Engine and transmission
Common problems across the XJ X351 range include a fractured bleed pipe outlet on the plastic coolant header tank. Look around the narrow hose that’s attached to the side of the header tank, close to the pressure cap, for traces of pink-coloured coolant. A new header tank costs around £90, whereas a used one is about a third of this price. There’s also a coolant housing in the middle of the vee of the diesel engine that can crack and leak, along with the water pump outlet on the nearside of the engine block.
Blocked breathers can result in oil being sprayed around the engine bay and fault codes raised. However, Matt Norbury at North Wales Jag explains that, “Oil contamination around the engine bay is down to either a cracked inlet manifold, which is very common, or a damaged O-ring on the breather pipe locating in the throttle body being incorrectly refitted.”
The diesel engine is equipped with a diesel particulate filter (DPF), which not only needs to regenerate, but also know when an oil and filter change has been conducted to allow for a regen, so a service reset is always essential. If you are looking at such a car, be cautious if there are no service records, or the seller doesn’t have any evidence that an oil and filter change was regularly completed along with a service reset. According to Eurojag, it sells plenty of 3.0-litre diesel engines to customers whose old engines have failed due to regeneration issues that can see excess fuel dumped into the engine oil.
Early diesels can suffer from a choked secondary turbocharger compressor shut-off valve vacuum actuator (CSOV) and a bypass valve blocked with carbon, but can sometimes be cleaned or otherwise replaced to fix running issues.
Other potential diesel trouble includes alternator failure, sometimes involving the failure of the clutch or voltage regulator. Aftermarket replacements cost from around £200, although some specialists we spoke to prefer a genuine alternator, which costs around £700. A used alternator costs around £120.
The 5.0-litre V8 can suffer from sticking valves, often caused by a build-up of carbon. A fuel additive may help to remove the carbon, but otherwise the cylinder head in question will need to be removed to extract and clean the valves and their seats. The timing chains on these engines can fail (they are used in other Jaguars), and we received mixed opinions from different independent Jaguar specialists – some have changed lots of them on V8 XJs, whereas others have not. There are also two different types of timing chain due to the depth of it. The cost of replacement varies greatly between the specialists we spoke to, from around £1,700 up to about £4,000. Should the worst happen and the engine fails, Eurojag sells used engines with the option for exchange.
The XJ X351 was only ever equipped with an automatic ZF gearbox, starting with the six-speed and changing to the eight-speed in autumn 2013. This is a familiar gearbox within the Jaguar range and seems not to require servicing, although some independent specialists recommend changing the oil and filter. “We recommend replacing the gearbox oil and filter at around 80,000 miles or ten years,” says Mark at E&E Services. “During the service, we also clear any transmission faults and reset adaptions. The only common issue with these transmissions is a leaking sump pan, but this is replaced during a gearbox service.”
The rear differential can suffer from a blocked breather, resulting in oil leaks and excessive wear. Eurojag sells these types of diff’ for around £300. The high-performance models may have an electronic active diff’, which controls the delivery of power to each driveshaft. If this fails, Eurojag sells used units for around £600.
Suspension, steering and brakes
The XJ X351’s suspension is similar to older XJs and such other models as the XF. At the front, there’s the familiar banana-shaped control arm, a single lower arm with a coil-over attached to it, an anti-roll bar and an upper wishbone. The front-most bush in the control arm can fail, resulting in uneven tyre wear. A new bush can be fitted if you have access to a hydraulic press, or a complete arm can be bought and fitted instead. Powerflex manufactures a set of polyurethane bushes for this arm that costs around £100. A standard replacement rubber bush costs around £40 and a complete aftermarket arm is about £70, whereas a genuine arm costs £230 or so, and a used genuine arm costs around £70. Tom Lenthall comments, “If you were replacing these arms or bushes, a four-wheel alignment would then be required. This is due to a camber adjustment bolt going through that bush.”
The bushes and ball-joint for the upper wishbone can wear. Aftermarket replacements cost around £80, whereas a genuine wishbone costs around £250.
At the rear, the XJ employs upper and lower arms with a track control arm and an air suspension damper that costs around £850 to replace (armour-plated XJs use traditional coil-overs at the rear).
Worn lower arm bushes are common across most Jaguars, resulting in uneven tyre wear and poor handling. A replacement aftermarket lower arm costs around £120, a genuine arm about £220, or a genuine used item from Eurojag is about £120.
During a test drive, listen for suspension-related knocking noises from the front and rear. These can be caused by a worn anti-roll bar droplink, worn mounts for the anti-roll bar, or a worn lower mounting bush for the front coil-over or rear air suspension damper (often a hollow rattle in this case).
Servo-assisted discs and calipers are fitted all round, and there is an electronic parking brake (EPB) on the rear brakes. The EPB must be set to service/engineering mode before working on the rear brakes and reset afterwards to align the pads, which also helps to avoid the problem of a dragging handbrake. Test for that by conducting a short drive without using the brakes, or using them as little as possible, switch off and place a hand close to each disc to feel for excessive heat and compare them to the front discs. Any that are hotter than the rest may have a problem of a dragging caliper/pad.
During a test drive, check the brakes don’t judder or pull to one side under normal braking. Such problems could suggest a warped disc (juddering) or a sticking caliper (pulling to one side). Routine servicing is often limited to a visual inspection of the brakes, so there’s no allowance to strip and clean them.
While there are plenty of cheap deals on aftermarket brake discs and pads, remember that this is a high-performance saloon that weighs almost two tons. However, many parts are shared across the range (the twin-piston caliper on the supercharged V8 is also fitted to the XKR X150 and XFR), so bargains can be found.
Interior and trim
One of the major issues with the XJ X351 concerns its glass sunroof. Dan at Elite & Performance Jags has repaired sunroofs where the frame has corroded, a repair that Jaguar has recorded on a bulletin, and also sells a satin black tape to cover over the corrosion (once it has been cleaned off). The repair takes between two and four hours. Says Dan, “It involves cleaning the surface corrosion away, treating and repainting the two sides and then applying the tape over the top to give a smooth satin black look again. If it’s caught early it’s sufficient, but we have seen a couple that were really badly corroded and it’s then only a cover up job for a year or two – the trouble is, the entire roof cassette would need to be changed.”
Door latch problems are not so common on the XJ X351, but can result in the failure to lock or unlock a door via the central locking. Some doors have a soft-close function, which assists the door when closing it. Eurojag sells replacement standard locks and soft-close locks which come with a three-month warranty, although Tom Lenthall doesn’t advise using second-hand locks as they are all prone to failure, “I think it would not be cost effective.”
Jaguar XJ X351: our verdict
Fans of the XJ may regard the X351 as too far removed from the familiar flowing lines of its seven predecessors, but even 12 years after it was launched at the Saatchi Gallery in London, and two years since production ceased, it still looks modern and unmistakably Jaguar.
Typical of any luxury saloon that was once unaffordable for most people, used prices are now more reasonable, making this the right time to think about buying one. Early 2010-2011 models can now be had for high four-figure sums; if you buy wisely you’ll get an awful lot of luxury saloon for the money.
