2010–2019
2013–2020
2016–2022
Jaguar's last traditional saloon goes head‑to‑head with the Mercedes S‑Class and BMW 7 Series. The XJ offers unmatched style and value, but can it compete with the tech‑laden Germans? Here's the honest verdict.
The XJ X351 is the best value for money, but the S‑Class is the better car overall. The Jaguar offers a unique blend of style, driving pleasure, and bargain prices – a good XJ can be had for £8,000–£15,000. The S‑Class W222 sets the benchmark in refinement and technology, while the 7 Series G11 is the dynamic all‑rounder. If you're budget‑conscious and value character, the XJ wins; for ultimate luxury and reliability, choose the S‑Class.
Full comparison, five‑year cost projection, and which flagship fits your needs below.
| Jaguar XJ X351 | Mercedes S‑Class W222 | BMW 7 Series G11 | |
|---|---|---|---|
| Years | 2010–2019 | 2013–2020 | 2016–2022 |
| Key Engines | AJ126 3.0 V6 SC · AJ133 5.0 V8 SC · 3.0 diesel | OM642 3.0 V6 diesel · M276 3.0 V6 petrol | B57 3.0 diesel · N63 4.4 V8 petrol |
| 2025 UK Enquiries | 151 [EM‑VERIFIED] | 55 [EM‑VERIFIED] | 150 [EM‑VERIFIED] |
| Typical Recon Fitted Cost | AJ126: £4,500–£7,500 | OM642: £3,200–£5,500 | B57: £5,000–£8,000 |
| Defining Failure | AJ126 cooling leaks | OM642 oil cooler seals | B57 coolant leaks |
| Best For | Style, value, driving character | Refinement, luxury, tech | Dynamics, efficiency, tech |
Enquiry volumes from 2025 Engine Failure Index. Costs are independent specialist supply‑and‑fit.
The S‑Class W222 is the overall winner – it sets the standard for luxury, refinement, and reliability, and its replacement costs are competitive. The 7 Series G11 is a close second, offering sharper dynamics and modern tech. The XJ X351 is the most charismatic and best value, but it's older, less reliable, and its running costs are higher. If you want the ultimate luxury experience and can afford the higher purchase price, choose the S‑Class; if you're on a budget and value style above all, the XJ is a bargain.
The X351 is Jaguar's last traditional saloon, a car that combines dramatic styling with a lightweight aluminium body. Its engine range includes the AJ126 3.0‑litre supercharged V6 (340–380 PS), the AJ133 5.0‑litre supercharged V8 (up to 550 PS in Supersport), and a 3.0‑litre V6 diesel. The AJ126 is the most common; its cooling system failures (water pump, crossover pipes) are well‑documented and can be costly [PATTERN DATA]. The AJ133 pre‑2013 has timing chain tensioner risks – see our AJ133 Chain Tensioner Failure page. Replacement costs are moderate: £4,500–£7,500 for the AJ126, £5,500–£9,000 for the AJ133. The XJ's aluminium construction gives it a weight advantage over its German rivals, contributing to sharp handling and good fuel economy for its size. Full specs on the AJ126 Knowledge Centre and AJ133 Knowledge Centre.
The W222 S‑Class is widely regarded as the benchmark for luxury saloons. Its engine line‑up includes the OM642 3.0‑litre V6 diesel (258 PS) and the M276 3.0‑litre V6 petrol (333 PS). The OM642 is known for oil cooler seal leaks – a labour‑intensive but manageable repair [PATTERN DATA]. Replacement costs are competitive at £3,200–£5,500 for the OM642, making it cheaper to replace than the XJ's AJ126. The S‑Class offers unparalleled ride comfort, cutting‑edge technology, and a cabin that feels a generation ahead of the XJ. It also has strong retained values. Enquiry volume is lower (55) due to its higher purchase price and lower parc volume, but it's a highly desirable used buy. See our repair‑or‑replace framework for cost guidance.
The G11 7 Series (2016–2022) is BMW's flagship, offering a blend of luxury and driving dynamics. Key engines are the B57 3.0‑litre six‑cylinder diesel (265–400 PS) and the N63 4.4‑litre V8 petrol (450–600 PS). The B57 is generally robust, with coolant leaks from expansion tanks being the main issue [PATTERN DATA]. Replacement costs are higher: £5,000–£8,000 for the B57, and £6,000–£10,000 for the N63. The 7 Series offers a more engaging drive than the S‑Class, with excellent refinement and a high‑tech interior. It's a strong all‑rounder, but its replacement costs are the highest among the three. Enquiry volume is comparable to the XJ at 150 requests [EM‑VERIFIED]. Full details on the B57 Knowledge Centre (though not a Jaguar engine, we can link to a relevant page – but we don't have a B57 page; we'll link to a general data page instead).
For a broader look at luxury car running costs, see our average replacement cost guide.
The XJ's strengths are value, style, and driving character. A good X351 can be bought for £8,000–£15,000 – significantly less than a comparable S‑Class (£15,000–£25,000) or 7 Series (£12,000–£22,000). The XJ's aluminium body makes it lighter and more agile than its rivals, and its interior, while dated, has a distinctive, cosseting feel. The supercharged V6 and V8 engines deliver a soundtrack that the diesel‑heavy German alternatives can't match. For those who prioritise individuality and driving pleasure over badge prestige, the XJ is a compelling proposition. However, you must budget for higher running costs and potential engine repairs – the XJ's older tech and known issues mean it's not the car for the faint‑hearted. Our XJ replacement economics guide helps you decide when to repair.
Over a typical 5‑year ownership window, the S‑Class is the cheapest to run among the three, thanks to lower replacement costs, better fuel economy (diesel versions), and stronger residuals. The 7 Series is slightly more expensive due to higher parts and labour costs. The XJ is the most expensive to run – its older engines are thirstier, its servicing costs are higher, and its probability of a major failure (cooling system, timing chain) is greater. However, the XJ's lower purchase price can offset these running costs, especially if you keep the car for a shorter period. For a full breakdown of repair costs, see our engine replacement cost guide.
Choose the XJ X351. It offers the most character for the least money. Buy a well‑maintained example with a service history and budget for cooling system preventative work.
Choose the S‑Class W222. It's the benchmark for a reason – incredible ride, quiet cabin, and strong reliability. The OM642 diesel is a great choice for economy.
Choose the 7 Series G11. It offers the best handling and a high‑tech interior. The B57 diesel provides excellent performance and economy.
Whichever you choose, always apply the repair vs replace framework before committing to a major repair – the 60% (Jaguar) or 70% (BMW/Mercedes) scrap threshold applies.
No – the XJ is the least reliable of the three, with known cooling system and timing chain issues. The S‑Class and 7 Series, especially with diesel engines, are generally more robust.
The S‑Class with OM642 diesel is cheapest at £3,200–£5,500 fitted. The XJ's AJ126 costs £4,500–£7,500, and the 7 Series B57 is £5,000–£8,000.
If you value style, driving character, and a bargain price, yes. But be prepared for higher running costs and potential repairs. For ultimate luxury and peace of mind, the S‑Class is the better choice.
Jaguar uses a 60% threshold: if the cost of a replacement engine exceeds 60% of the vehicle's market value, it's usually cheaper to scrap the car. We explain this in our repair‑or‑replace framework.
356 Combined Enquiries - real data from 2025.
15+ Vetted Specialists - independent and experienced.
100% Independent - no manufacturer influence.
Clear Verdict - we name a winner and explain why.
Compare quotes from our vetted specialist network for any of these flagship engines.
COMPARE QUOTES NOW → FIND YOUR ENGINE FIRST