Jaguar XJ-S, Frequently Asked Questions

How much does an XJ-S cost in Australia?

Less than you’d think. A running V12 coupe in presentable condition starts around $15,000-25,000 AUD. A good six-cylinder coupe can be found for $10,000-25,000 AUD. Convertibles are more, a decent V12 convertible sits at $30,000-50,000 AUD, with top examples pushing higher.

Facelift models (1991-96) command a premium of roughly 20-40% over equivalent pre-facelift cars. The 6.0 V12 facelift convertible is the most expensive variant, with excellent examples reaching $60,000-70,000 AUD.

Projects and rough runners exist below $10,000, but be very careful. A $5,000 XJ-S that needs $15,000 in work is not a bargain. The purchase price is the smallest part of XJ-S ownership, it’s the maintenance and repairs that cost real money.

Should I buy the V12 or the six-cylinder?

This is the fundamental XJ-S question, and there’s no wrong answer, just different priorities.

Buy the V12 if: You want the full XJ-S experience. The V12 is what makes this car special, the silky power delivery, the extraordinary sound under load, the effortless torque. A V12 XJ-S on a quiet country road is one of motoring’s great experiences. You need to accept the fuel consumption (15-20 L/100km), the more complex maintenance, and the higher running costs. If you’re prepared for that, the V12 is magnificent.

Buy the six-cylinder if: You want a grand touring Jaguar you can use regularly without financial anxiety. The 4.0-litre AJ16 is a strong, smooth, modern engine that’s reliable and relatively economical (12-15 L/100km). It has more than enough performance, 0-100 km/h in about 7.5 seconds, and the maintenance costs are substantially lower. The six-cylinder XJ-S is the sensible choice, and it’s still a genuinely enjoyable car.

The sweet spot: 4.0-litre facelift coupe. Best build quality, best engine in the six-cylinder range, reasonable running costs, and the facelift styling is the most attractive. This is the XJ-S for someone who wants to drive it, not just admire it.

What’s the difference between pre-HE and HE V12 engines?

The pre-HE V12 (1975-1981) uses flat-head combustion chambers and is spectacularly thirsty, 20-25 L/100km in normal driving. It also runs hotter and is more sensitive to fuel quality.

The HE (High Efficiency) V12, introduced in 1981, uses Michael May’s fireball combustion chambers with a higher compression ratio and more efficient burn. Fuel consumption drops to 15-18 L/100km (still not exactly frugal, but a genuine improvement). The HE also produces more low-end torque, making it a better road engine.

Later cars received the 6.0-litre V12 (from 1993), which is essentially the HE design with increased capacity. More power, similar economy, and generally considered the best of the V12 variants.

If you’re buying a V12, get at least an HE. The pre-HE cars are significantly more expensive to run and harder to tune correctly.

Is the GM TH400 automatic really that good?

Yes. The GM Turbo-Hydramatic 400 is one of the most reliable automatic gearboxes ever mass-produced. It was designed for American V8 trucks and muscle cars, which means it’s hilariously over-engineered for the Jaguar V12’s torque output. Regular fluid and filter changes (every 40,000 km) keep it happy indefinitely.

The earlier Borg-Warner BW66 (fitted to early cars) is less robust. It can handle normal driving but doesn’t tolerate high heat or hard use as well as the GM unit. If your car has a BW66, it’s worth considering a TH400 conversion when the time comes, kits are available and well-documented.

Later cars received the GM 4L80-E four-speed electronic automatic, which is also excellent.

Can I use an XJ-S as a daily driver?

You can, with some caveats. The XJ-S is comfortable, fast, and practical enough for daily commuting. The cabin is spacious for two (the rear seats in the coupe are decorative rather than functional), the boot is a decent size, and visibility is reasonable.

The caveats: fuel cost is significant if you’re doing daily kilometres in a V12. Parking a wide, long car in tight city spaces requires nerve. The air conditioning needs to work in Australian summers. And you need to accept that something will occasionally go wrong, a relay fails, a hose leaks, a sensor throws a wobble. This is par for the course with a 30-50 year old car.

The six-cylinder facelift models are the best daily drivers. More economical, better built, and with fewer complex systems to fail. The V12 is better suited to weekend and touring use unless you have a robust maintenance budget.

How much does it cost to maintain?

Budget $2,000-4,000 AUD per year for a well-sorted V12, covering routine servicing, oil changes (it holds nearly 12 litres), ignition consumables, and the inevitable small repairs. The six-cylinder is cheaper, $1,500-2,500 AUD per year.

Major items are additional. A cooling system overhaul ($3,000-5,000), head gasket replacement ($8,000-12,000), A/C rebuild ($2,000-5,000), suspension refresh ($2,000-4,000), these are the bigger-ticket items that arise over ownership. Budget for them by setting aside money annually.

Fuel is a real ongoing cost for the V12. At 18 L/100km and current fuel prices, a car doing 8,000 km per year burns roughly $3,000 in 98 RON.

What should I look for when buying?

In order of importance:

1. Cooling system (V12): This is the number one priority. Check coolant condition, verify fan operation, look for head gasket weeping, and ask about cooling system maintenance history. A V12 with a poorly maintained cooling system is a ticking time bomb.

2. Rust: Sills, rear wheel arches, boot floor, front wings. Poke them with a screwdriver. Don’t trust underseal, it hides rot.

3. Service history: A documented maintenance record is worth thousands in purchase price. An XJ-S with no service history is a gamble.

4. Electrics: Test everything, every switch, every light, every window, A/C, cruise control. Electrical issues are time-consuming and frustrating to sort.

5. Gearbox: Confirm whether it’s a TH400 or BW66. The TH400 is the one you want.

6. General condition: Interior trim, paint, chrome (or lack thereof), panel fit. These indicate overall care.

Where do I find parts?

Parts availability is excellent:

• SNG Barratt (UK), comprehensive catalogue, ships to Australia regularly.
• David Manners (UK), strong Jaguar parts inventory.
• Martin Robey (UK), particularly good for body panels.
• Welsh Enterprises (USA), good range, sometimes better pricing on certain items.
• Australian Jaguar specialists, most capital cities have dedicated workshops that stock common parts.
• JDCA network, members trade parts, and the club’s connections can locate rare items.

The XJ-S shares many components with the XJ saloon range, which broadens the parts supply base considerably. Mechanical parts are generally affordable. Body panels and trim are more expensive but available. Electrical components can be sourced from specialists or, in some cases, from general automotive suppliers (relays, sensors, etc. are often standard Bosch or Lucas items).

Is the XJ-S rust-prone?

Less so than the E-Type, but yes, it’s a steel-bodied car from an era when rust protection was improving but not yet comprehensive. The main areas to watch are sills, rear wheel arches, boot floor, door bottoms, and front wings.

Australian-delivered cars tend to be less rusty than imports from the UK or Europe (no road salt, drier climate). But neglected cars rust regardless of location, blocked drains, failed seals, and standing water do the damage.

Rust on an XJ-S is generally repairable. Replacement panels are available for common areas, and the bodywork is less complex than the E-Type’s monocoque. A car with minor surface rust is manageable. A car with structural sill rot needs careful assessment.

What about the flying buttress styling? Will I get used to it?

You’ll go through three phases. First: “Those buttresses are weird.” Second: “I suppose they’re distinctive.” Third: “I can’t imagine the car without them.”

The flying buttresses are the XJ-S’s most divisive design element, but they’re also what gives the car its identity. Without them, it’s just another 1970s coupe. With them, it’s unmistakably an XJ-S. They also serve a functional purpose, they improve rear three-quarter visibility and add structural rigidity to the roofline.

The facelift cars soften the buttresses slightly with revised trim, and the convertible eliminates them entirely. But if you’re buying a coupe, embrace the buttresses. They’re part of the deal.

Is the XJ-S a good investment?

Values are rising, particularly for V12 convertibles and late facelift models. The XJ-S was undervalued for years, seen as a cheap, complex car that no one really wanted. That perception is changing as the car’s qualities are reappraised and the supply of good examples diminishes.

That said, the XJ-S is not an investment-grade classic in the way an E-Type is. It’s a car you buy because you love it, with the reasonable expectation that values will hold or appreciate modestly. The maintenance costs mean you won’t make money on the deal unless values jump significantly.

The best “investments” in XJ-S terms are: V12 convertibles (facelift especially), low-mileage facelift coupes, and any genuinely exceptional example with full documented history. These are the cars that will appreciate most as the market matures.

Should I join the JDCA?

Absolutely. The Jaguar Drivers Club of Australia has strong XJ-S representation across all state branches. You’ll get access to experienced owners who’ve dealt with every problem, specialist recommendations, technical resources, and a social network of people who understand why you’d choose to own a complex British GT over something sensible.

The club also organises events, runs, concours, technical days, that are genuinely enjoyable and useful. Insurance discounts through club schemes can offset the membership cost.

Membership is typically $80-120 AUD per year. It’s one of the best investments in XJ-S ownership.

What modifications are worth doing?

Essential upgrades:

• Cooling system refresh: Not optional on a V12. Aluminium radiator, new hoses, aluminium header tank, verified fan operation. Do this before anything else.
• Electronic ignition: Pertronix or similar. Replaces the failure-prone Lucas ignition on pre-Marelli cars. Better starting, better running, less maintenance.
• Stainless steel exhaust: The original mild steel systems rot. Stainless lasts and sounds better.

Worthwhile improvements:

• Polyurethane suspension bushes: Firmer, longer-lasting, better handling.
• Modern stereo with Bluetooth: Keep the original head unit facia but fit modern internals. The original radio is useless.
• LED interior lighting: Subtle improvement, less battery drain.

Leave alone: The exterior styling, the engine specification, and the overall character. The XJ-S is best appreciated as a well-maintained original, not a modified one. Keep original parts if you do upgrade, reversibility protects value.