The Jaguar XK X150 is an aluminium-bodied grand tourer offered as both coupe and convertible. The 5.0-litre AJ133 V8, introduced with the 2009 facelift, produces 385 hp in naturally aspirated form or 510 hp (550 hp in XKR-S) with a Roots-type supercharger. Paired exclusively with a ZF 6-speed automatic, it combines effortless V8 cruising with genuinely sharp handling from its lightweight construction.· more· less
Aluminium body: no rust concernsRobust AJ133 V8 core design
Timing chain tensioner wear riskCoolant system has multiple weak points
Buy if: You want a characterful British GT with V8 sound and can budget for specialist-level maintenance and potential cooling system repairs.
Avoid if: You cannot absorb repair bills in the €2,000-5,000 range or need a car that any general garage can service confidently.
Hard steel tensioner plunger wears a groove into the aluminium/plastic guide rail, causing chain slack · more· less
The AJ133 5.0 V8 uses timing chain tensioners where a hardened steel pin presses against a guide rail made of aluminium with a plastic surface. Over time, this pin wears a groove into the guide, allowing the chain to develop slack. The issue is documented from around 80,000 km onward, with isolated cases as early as 60,000 km. Symptoms include a rattle or whine on cold start that may persist for several seconds. If caught early, replacing tensioners, guides, and chains costs €3,000-6,000 at a specialist. If the chain skips and causes valve-to-piston contact, engine rebuild costs can reach €8,000-15,000. Engines from 2015 onward received improved components, but all X150 5.0 cars (2009-2014) use the earlier design. This affects both naturally aspirated and supercharged variants equally.
Water pump seal failure
€600 - 1,5002 of 8
Coolant migrates past the shaft seal, corroding the bearing and causing external leaks · more· less
The mechanical water pump is widely cited as the most common AJ133 issue. Coolant passes the shaft seal and enters the bearing housing, corroding it so the impeller shaft loses support. Early production pumps used plastic impellers prone to cracking; Jaguar released an updated pump with a metal impeller. Failures are typically seen between 60,000 and 100,000 km. Warning signs include a small coolant weep from the pump weep hole, low coolant warnings, or a visible drip at the front of the engine. Replacement costs €600-1,500 depending on whether an independent specialist or dealer performs the work. The pump itself costs €200-400 and labor is approximately 3-4 hours. This affects both naturally aspirated and supercharged models.
Coolant crossover pipe failure (supercharged)
€1,200 - 3,0003 of 8
Plastic PA66 nylon pipe in the engine valley splits along its welded seam or O-ring groove erodes · more· less
The supercharged XKR and XKR-S use a molded nylon coolant crossover pipe (valley pipe) that sits beneath the supercharger in the engine V. Over time the plastic becomes brittle, the welded seam splits, or the O-ring groove erodes, causing sudden major coolant loss. Because the pipe is buried under the intake manifold and supercharger, leaks are difficult to spot until coolant loss is significant. Repair requires removing the supercharger, which is approximately 5-6 hours of labor alone. Total repair cost at a specialist runs €1,200-3,000 including parts, gaskets, and labor. Many specialists recommend replacing all accessible coolant pipes and seals while the supercharger is off. The naturally aspirated 5.0 also has coolant pipes in the valley but they are far easier to access and less prone to this specific failure mode.
ZF 6HP28 mechatronic unit deterioration
€1,500 - 3,0004 of 8
Bridge seal hardens and conductor plate degrades, causing hydraulic pressure loss and shifting faults · more· less
The ZF 6HP28 automatic transmission uses a bridge seal (figure-8 sealing sleeve) between the valve body and transmission case that hardens and cracks with age. The conductor plate and solenoids also degrade, leading to loss of line pressure. Symptoms include harsh or delayed shifts, flaring between gears, and transmission fault warnings. Jaguar marketed the transmission fluid as a lifetime fill, but specialists strongly recommend changing the ATF and filter every 60,000-80,000 km to extend the mechatronic unit's life. A mechatronic rebuild at a gearbox specialist costs €1,500-3,000, while a full transmission rebuild can reach €4,000-6,000. Many owners misdiagnose this as a dead gearbox when only the mechatronic seals and module need attention.
Spring-type torsional coupler breaks inside the supercharger nose, creating a metallic rattle at idle · more· less
The Roots-type supercharger on XKR and XKR-S models uses a spring-loaded torsional coupler (isolator) in the nose cone that absorbs drive pulses. Over time the spring breaks and allows the drive forks to chew the coupling, producing a distinctive metallic rattle most audible at idle. This is typically observed after 80,000 km or 8+ years. The repair requires removing the supercharger to access the nose cone. An independent specialist typically charges €800-1,200 for coupler replacement, while a Jaguar dealer may quote €2,000-3,500. Supercharger nose cone refurbishment services are also available as an alternative to full replacement. This issue does not affect the naturally aspirated 5.0 XK.
CATS adaptive damper failure
€800 - 2,5006 of 8
Electronic valve components inside the dampers wear out, causing oil leaks and loss of adaptive function · more· less
The Computer Active Technology Suspension (CATS) system uses electronically adjustable dampers that allow the driver to choose between comfort and sport modes. The electronic components tend to degrade by around 100,000 km, and the seals can begin to leak oil. A leaking damper is the most visible sign of failure. Replacement costs approximately €350-500 per damper plus 1-2 hours of labor per corner. Most failures occur in pairs (front or rear axle), so budget €800-1,500 for a pair. A full set replacement runs €1,500-2,500 including labor. Some owners have had original units reconditioned, as failures are often limited to the seals rather than the electronic valve itself.
Battery drain and parasitic draw
€200 - 6007 of 8
An abnormal parasitic draw drains the battery in days; healthy cars settle below 35 mA after shutdown · more· less
Jaguar specifies a parasitic draw below 35 mA once the X150 has fully shut down, typically within three minutes of locking. A car that stays well above that has a diagnosable fault rather than normal behaviour, and it can flatten a healthy battery in one to two weeks of standing. Jaguar bulletin JTB00213 documents one such fault, a MOST ring or Integrated Control Module that stays awake and pulls up to 1.6 A, limited to 2010-2011 XK cars in VIN range B32753-B42709. Other common culprits are the Body Control Module and Battery Power Module staying partially active. The fix involves diagnosis (isolating circuits fuse by fuse), a module replacement or software update, and usually a fresh battery, since repeated deep discharge ruins one. Battery replacement alone costs €150-300 for a quality AGM unit. A trickle charger (CTEK or similar) during long periods of standing is strongly recommended by all XK specialists.
AC evaporator drain tube blockage
€200 - 1,0008 of 8
Duckbill drain valve dries up and sticks shut, causing condensate to flood the passenger footwell · more· less
The air conditioning evaporator uses a duckbill-type one-way drain valve designed to keep insects out. Over time this rubber valve dries up and sticks together, preventing condensate from draining. Water backs up into the blower motor housing and runs down into the passenger footwell. This was addressed by Technical Service Bulletin JTB00121 for early VINs, but it can affect any X150 regardless of production date. A temporary fix involves blasting the AC on maximum fan speed with face vents only to force water through. The permanent fix requires replacing the drain tube with a modified version. On some cars this can be done from underneath by dropping the gearbox cross-member slightly (€200-400), but a full proper repair requires partial dashboard removal (€600-1,000). Check for damp carpet on the passenger side during any pre-purchase inspection.
Fundamentally sound GT, but cooling system and tensioners need monitoring
The AJ133 5.0 V8 is a capable engine that can exceed 150,000 km when properly maintained. The naturally aspirated version is simpler and avoids supercharger-specific issues. The supercharged XKR adds complexity with the nose cone coupler and buried coolant pipes. Across both variants, the cooling system (water pump, crossover pipes, thermostat) is the area demanding the most vigilance. Timing chain tensioner wear is a known design weakness but is not as severe on the AJ133 as on earlier Jaguar V8 engines. Regular specialist servicing with correct 5W-20 oil, proactive gearbox fluid changes, and a trickle charger for periods of inactivity significantly reduce the risk of expensive surprises.
Service history
Complete Jaguar dealer or specialist records essential. Verify correct 5W-20 oil was used on all 5.0 services and that gearbox fluid has been changed at least once.
Tires
Staggered setup (245/40R19 front, 275/35R19 rear). Check tread depth, date codes, and inner-edge wear on rears. 20-inch wheels are more susceptible to pothole damage.
Cold start
Must start the engine completely cold. Listen for any rattle or whine in the first 30 seconds that could indicate timing chain tensioner wear.
Test drive
Minimum 30 minutes including motorway speeds. Get the gearbox fully up to temperature and check for any shift hesitation or harshness.
Specific for this vehicle
Check coolant level and look for leaks around the water pump
Low coolant or visible weeping at the front of the engine indicates water pump seal failure. Check the expansion tank for correct level and clean coolant.
Listen for supercharger rattle at idle (XKR/XKR-S)
With the engine warm and idling, listen for a metallic rattle from the supercharger area. This indicates coupler (isolator) failure inside the nose cone.
Feel the passenger footwell carpet for dampness
Wet or musty carpet on the passenger side indicates a blocked AC evaporator drain. Check both footwells and under the carpet if possible.
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Test all CATS damper modes
Switch between comfort and sport suspension settings during the test drive. Clunking, excessive body roll in sport mode, or visible oil on damper bodies indicates failure.
Check battery age and ask about parasitic draw
Ask the owner how often the car is driven and whether the battery needs frequent jump-starting. A battery older than 3-4 years should be tested under load. A car that goes flat within two weeks of standing has an abnormal draw that needs diagnosis, not just a new battery.
Verify gearbox fluid has been changed
Despite Jaguar's lifetime fill claim, the ZF 6HP28 needs ATF changes every 60,000-80,000 km. Dark or burnt-smelling fluid is a warning sign.
Inspect aluminium body for repair quality
The XK has an all-aluminium body that requires specialist repair techniques. Look for paint bubbling or poor panel gaps that indicate previous damage repaired by a non-specialist.
Recalls and Technical Service Bulletins
Fuel pump relay not energized after startup (2010-2011 models with 5.0L engine)Verify completed
Front side lamps turning off after approximately 5 minutes (2012-2015 models)Verify completed
Power steering hose, loss of assistance with fire risk (2010-2011 petrol XK, VIN B35314-B38302)Critical - verify completed
Rear toe link, XKR-S GT only, J037 / UK R/2014/041 (March-December 2013 production)Verify if applicable
Contact Jaguar with the VIN to verify all recalls have been completed. The power steering hose campaign on 2010-2011 petrol cars (VIN range B35314-B38302) is the important one because of the fire risk. The rear toe link campaign applies only to the XKR-S GT.
Warranty Status
Factory warranty (3 years / unlimited km)Expired on all XK 5.0 V8 models
Jaguar approved used warrantyAvailable through Jaguar dealers on qualifying vehicles
Aluminium body corrosion6-year perforation warranty (expired on all models)
All Jaguar XK 5.0 V8 models (2009-2014) are well outside their original 3-year factory warranty. Third-party extended warranties are available but often exclude known AJ133 weak points such as timing chain tensioners and coolant system components. Review exclusion lists carefully before purchasing.
Sources: Research draws on model-specific owner forums and owner communities, recall information from official authorities, German automotive press, and multiple workshop cost references cross-checked against each other.
This report is for informational purposes only and does not constitute professional advice. Estimates may be inaccurate. Always have a qualified specialist inspect the vehicle before purchase. We accept no liability for decisions made based on this information.
