Jaguar Xj (X351) | History, Reliability & Buying Guide

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Jaguar XJ (X351): A Comprehensive Guide

The Jaguar XJ (X351) is the fourth and final generation of the iconic XJ luxury sedan, produced from 2009 to 2019. Representing a significant departure from its traditionally styled predecessors, the X351 embraced a sleek, contemporary design while retaining the XJ's signature blend of performance, luxury, and refinement. Positioned as a flagship model, it directly competed with the likes of the Mercedes-Benz S-Class, BMW 7 Series, and Audi A8, catering to discerning buyers seeking a sophisticated and driver-focused alternative in the full-size luxury segment.

Generations

X351 (2009-2019)

2009: Launch of the X351, featuring a dramatically different design with a coupe-like roofline, wraparound rear window, and prominent grille. Engine options included naturally aspirated and supercharged V8 petrol engines.

2010: Introduction of the long-wheelbase (LWB) version, offering increased rear legroom and enhanced luxury features.

2012: A 2.0-liter turbocharged four-cylinder petrol engine and a 3.0-liter V6 diesel engine were added to the range, broadening the model's appeal and improving fuel economy. Updated infotainment system introduced.

2014: Minor cosmetic updates, including revised rear seats and improved interior materials. Introduction of the XJR performance model with a more powerful supercharged V8.

2016: InControl Touch Pro infotainment system introduced with a larger touchscreen and faster processor. Refinements to the suspension for improved ride comfort.

2018: A range of cosmetic updates and trim level revisions. The XJ50 special edition was launched to celebrate the XJ's 50th anniversary.

2019: Production of the X351 ended.

Reliability & Common Issues

The X351, while a beautiful and luxurious car, is not without its potential issues. Regular maintenance is crucial to ensure reliability.

Engine Problems:

Timing Chain Tensioners (V8 Engines): A common issue, particularly on earlier models. The plastic tensioners can fail, leading to timing chain slack and potentially catastrophic engine damage. Listen for a rattling noise at startup, especially when cold. Replacing the tensioners with updated metal versions is a recommended preventative measure.

Supercharger Issues (Supercharged Engines): Supercharger bearings and couplers can wear out over time, leading to noise and reduced performance. Regular supercharger oil changes are essential.

Cooling System Leaks: Watch for leaks around the water pump, thermostat housing, and radiator. Overheating can cause serious engine damage.

Oil Leaks: The V8 engines are prone to oil leaks, especially from valve cover gaskets and the rear main seal.

Diesel Particulate Filter (DPF) Issues (Diesel Engines): Short trips can prevent the DPF from regenerating properly, leading to clogging and reduced performance. Ensure the car is driven on longer journeys regularly.

Electrical Problems:

Infotainment System Glitches: The earlier InControl Touch systems were known for being slow and buggy. The updated InControl Touch Pro system is significantly better but can still occasionally experience glitches. Check all features are functioning correctly before purchase.

Battery Drain: The X351 has a complex electrical system that can be prone to parasitic battery drain. Ensure the battery is in good condition and properly maintained.

Sensor Failures: Various sensors, such as oxygen sensors and crankshaft position sensors, can fail over time, causing engine management issues.

Air Suspension Problems: The air suspension system can experience leaks or compressor failures, resulting in a sagging ride height or uneven stance. Inspect the air struts and compressor for signs of wear or damage.

Transmission Issues:

ZF 6HP28 (Older Models): Although a reliable transmission, the ZF 6HP28 used in earlier models should have regular fluid changes (every 50,000-60,000 miles) to prevent issues.

ZF 8HP Transmission (Later Models): The ZF 8HP transmission is generally considered more robust than the 6HP28. However, regular fluid changes are still recommended.

Body and Interior Issues:

Rust: While Jaguar has improved rust protection, check the sills, wheel arches, and underbody for any signs of corrosion, especially in areas with harsh winters.

Interior Trim: The interior is generally well-built, but leather can wear, and wood veneer can crack or delaminate. Inspect the interior carefully for any signs of wear and tear.

Driving Experience

The X351 offers a refined and engaging driving experience. It balances comfort with sporty handling, making it a rewarding car to drive.

Pros:

Comfortable Ride: The air suspension provides a smooth and comfortable ride, especially on long journeys.

Responsive Handling: Despite its size, the X351 handles surprisingly well, with precise steering and good body control.

Powerful Engines: The range of engines, from the efficient four-cylinder to the exhilarating supercharged V8, offers something for everyone.

Luxurious Interior: The interior is beautifully appointed with high-quality materials and comfortable seats.

Distinctive Styling: The X351's design is a head-turner, setting it apart from its more conservatively styled rivals.

Cons:

Infotainment System (Earlier Models): The earlier InControl Touch system can be frustrating to use.

Reliability: Potential for some expensive repairs, especially if maintenance has been neglected.

Running Costs: Fuel consumption can be high, especially with the V8 engines, and maintenance costs can be significant.

Rear Headroom (Sloping Roofline): The sloping roofline can impinge on rear headroom, particularly for taller passengers.

Buying Advice

When buying a used X351, careful inspection and research are essential.

Years to Look For:

2016 and later: These models benefit from the improved InControl Touch Pro infotainment system, refined suspension, and generally have fewer early production issues.

XJR Models: For performance enthusiasts, the XJR offers a thrilling driving experience. Ensure it has been well-maintained.

Years to Avoid (or Exercise Caution):

Early Production Years (2009-2011): These models may be more prone to timing chain tensioner issues and infotainment system glitches. A thorough pre-purchase inspection is crucial.

Pre-Purchase Inspection Checklist:

Engine: Listen for any unusual noises, especially at startup. Check for oil leaks. Get a compression test if possible.

Transmission: Check for smooth shifting and any signs of hesitation or slipping. Inquire about transmission fluid changes.

Suspension: Check the air suspension system for leaks or compressor failures. Ensure the car sits level.

Electrical System: Test all electrical components, including the infotainment system, power windows, and lights.

Body and Interior: Inspect for rust and damage to the interior trim.

Service History: A complete service history is crucial to understanding the car's maintenance record.

Recommendations:

Get a Pre-Purchase Inspection: Have a qualified mechanic inspect the car before you buy it.

Factor in Maintenance Costs: Budget for potential repairs and regular maintenance.

Consider an Extended Warranty: If possible, purchase an extended warranty to protect yourself against unexpected repairs.

Don't Be Afraid to Walk Away: If you find any red flags, don't hesitate to walk away and find another car. There are many X351s available on the market.

The Jaguar XJ (X351) is a beautiful and rewarding car to own, but it's important to be aware of its potential issues. With careful research and a thorough pre-purchase inspection, you can find a well-maintained example that will provide years of luxurious and enjoyable driving.
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