Jaguar XJ6, Frequently Asked Questions

How much does a Jaguar XJ6 cost in Australia?

The XJ6 is one of the great classic car bargains. A running, presentable Series 3 4.2 can be found for $8,000-20,000 AUD. A Series 2 is even cheaper, $8,000-15,000 for a decent driver. Series 1 cars have climbed further, sitting at $15,000-40,000+ for good examples, reflecting their increased collectibility.

V12 models (XJ12, Sovereign V12, Daimler Double Six) add 30-50% to the equivalent six-cylinder price. Daimler-badged versions command a modest 10-20% premium over Jaguar-badged cars with the same mechanicals.

Long wheelbase models are generally worth slightly more than standard wheelbase, but the difference is modest unless the car is in exceptional condition.

Projects and non-runners exist for under $5,000, but approach them with extreme caution. A cheap XJ6 with hidden rust and deferred maintenance will cost more to sort than a car bought right in the first place.

Which series should I buy?

Series 3 for most people. It’s the most refined, has the best parts supply, and benefits from years of development. Late-production Series 3 cars (1987 onwards) with Bosch ignition are the most reliable. The Sovereign trim level gives you the full luxury experience. This is the XJ6 you can actually use.

Series 1 for the purist. The most beautiful, the most collectible, and increasingly the most valuable. If you care about aesthetics and historical significance above practicality, the Series 1 4.2 is the one. Be prepared for Lucas electrics, SU carburettors, and generally more maintenance.

Series 2 for the bargain hunter. Nobody loves the raised bumpers, which means prices are low. You get essentially the same car as the Series 1, same engine, similar running gear, for significantly less money. If you can look past the cosmetic changes, it’s a smart buy.

Avoid the 2.8-litre engine in any series. It’s underpowered, unreliable, and there’s no reason to choose it when 4.2 cars are plentiful and affordable.

Can I use an XJ6 as a daily driver?

Many people do, particularly with Series 3 models. The car is comfortable, refined, and practical enough for regular use. The boot is large, the cabin is spacious for four (five at a squeeze), and the ride quality makes traffic bearable.

The caveats are fuel cost (14-18 L/100km for the 4.2, more for the V12), the need for regular maintenance, parking a large car in tight spaces, and the likelihood that something minor will need attention periodically. Air conditioning is essential in Australian conditions, make sure it works before committing to daily use.

The six-cylinder Series 3 with Bosch ignition is the most viable daily driver. Electronic ignition eliminates the most common roadside failure, and the GM TH400 automatic is essentially unbreakable. Budget for annual servicing, keep on top of the cooling system, and the car will be dependable.

V12 models are less practical as daily drivers due to fuel consumption and more complex maintenance requirements. Save the V12 for weekends and touring.

What’s the difference between Jaguar and Daimler versions?

Mechanically, nothing. The Daimler Sovereign (later just Daimler) uses the same engine, gearbox, suspension, brakes, and body structure as the equivalent Jaguar XJ6 or Sovereign.

The differences are cosmetic and trim-related: the Daimler has a distinctive fluted grille (replacing the Jaguar’s horizontal-bar grille), Daimler badges, and typically higher-specification interior trim, more wood, better leather, additional equipment depending on the specific model year.

The Daimler Double Six is the V12 version, equivalent to the Jaguar XJ12 or Sovereign V12.

Daimler versions command a modest premium (10-20%) in the used market, primarily based on the higher trim level and the perceived prestige of the Daimler badge. For practical purposes, buy whichever version is in better condition, the badge on the grille doesn’t affect how the car drives.

How reliable is the XK engine?

Remarkably reliable for a design from the 1940s. The XK inline-six is one of the most proven engines in automotive history, it powered everything from Le Mans winners to London taxis across a 44-year production run. A well-maintained 4.2 XK will cover 200,000+ km without major drama.

The engine’s weaknesses are well-known and manageable: oil leaks from gaskets and seals (universal), cooling system marginal in hot conditions (addressable with upgrades), timing chain stretch over high mileages (routine replacement), and the need for regular valve adjustments on some specifications.

The key word is “well-maintained.” The XK engine tolerates neglect poorly. Oil changes every 5,000-8,000 km with quality oil, regular coolant changes, attention to the timing chain and valve clearances, and prompt attention to any overheating, do these things and the engine will serve you well.

Should I worry about Lucas electrics?

On Series 1 and 2 cars, yes. Lucas ignition components are the single most common cause of roadside failure on these cars. Points, condensers, distributor caps, and rotor arms all fail with depressing regularity. The famous “Lucas, Prince of Darkness” jokes exist for a reason.

The fix is simple: fit an electronic ignition conversion (Pertronix or similar). It replaces the failure-prone points and condenser with a solid-state module. Better starting, more consistent running, and dramatically improved reliability. It’s the first modification anyone should make to a Series 1 or 2 XJ6.

Series 3 cars with Bosch ignition are significantly better. The Bosch system is more reliable, easier to diagnose, and parts are more readily available. If you’re buying a Series 3, try to get a late-production car with Bosch ignition, it makes a real difference to daily usability.

The rest of the electrical system (windows, locks, instruments, lighting) uses Lucas components regardless of series. These are age-related rather than design-related failures, clean connections, good earth points, and regular attention keep them working. A full rewire with a modern harness is the nuclear option for cars with pervasive electrical gremlins.

What are the main rust areas?

The same as every Jaguar from this era, in roughly this order of severity:

1. Sills (inner and outer), structural, critical, expensive to repair
2. Floor pans, structural, hidden under carpet, often worse than they look
3. Rear wheel arches and lower rear quarters, progressive, gets expensive if ignored
4. Boot floor and spare wheel well, water ingress from failed seals
5. Front wings, bolt-on panels, replaceable, but indicate general condition
6. A-pillars and windscreen surround, from failed windscreen rubbers
7. Subframe mounting points, safety-critical

Australian-delivered cars are generally better than imports. But “better” doesn’t mean “immune”, check every area carefully on any car you’re considering.

A magnet and a screwdriver are your best friends when inspecting an XJ6. Don’t trust underseal. Don’t trust fresh paint on the sills. And don’t buy a car without getting underneath it with a torch.

How much does maintenance cost?

Budget $2,000-4,000 AUD per year for routine maintenance on a sorted six-cylinder car. This covers annual servicing, oil changes, brake fluid, coolant, and the inevitable small repairs. The XK engine is not expensive to maintain, it’s simple, well-understood, and parts are affordable.

V12 models cost 30-50% more, more oil, more spark plugs, more ignition components, and generally more specialist time for any job.

Major items are additional: cooling system overhaul ($1,000-2,500), suspension refresh ($2,000-4,000), brake overhaul ($1,500-3,000), A/C restoration ($2,000-5,000). These arise over years of ownership and should be budgeted for as part of the total cost.

The purchase price is the smallest part of XJ6 ownership. A $10,000 car that needs $8,000 in deferred maintenance is more expensive than a $15,000 car that’s already sorted. Always buy the best condition you can afford.

Where do I find parts?

Parts availability is excellent, particularly for the Series 3:

• SNG Barratt (UK), comprehensive XJ parts catalogue, ships to Australia.
• David Manners (UK), strong Jaguar inventory, good for mechanical parts.
• Martin Robey (UK), particularly good for body panels and trim.
• JDCA network, club members trade parts, and the registers can locate rare items.
• Australian Jaguar specialists, workshops in every major city stock common items.

The XK engine shares components with the E-Type and XJ-S, broadening the supply base. Suspension and brake components are largely shared with the XJ-S. This parts commonality is one of the XJ6’s great advantages, you’re buying into a well-supported ecosystem, not an orphaned model.

Series 1 cars have slightly harder-to-find trim and brightwork, but even these are available through specialists.

Is the V12 XJ worth the extra money?

Only if you genuinely want the V12 experience and can afford the running costs.

The V12 XJ (XJ12, Sovereign V12, Daimler Double Six) offers something the six-cylinder can’t match: a level of mechanical refinement that’s almost supernatural. At idle, the engine is virtually silent. At speed, the power delivery is effortless and smooth in a way that even the lovely XK six can’t replicate. It’s the ultimate expression of the XJ concept, a luxury saloon powered by an engine of extraordinary sophistication.

The costs are real: 20-25 L/100km fuel consumption, more complex maintenance, cooling system challenges, and higher parts costs for anything engine-specific. A V12 XJ costs roughly 40-60% more per year to run than a six-cylinder equivalent.

If you want a V12, the Series 3 Daimler Double Six HE is the sweet spot, the HE engine is more economical than the pre-HE, the Series 3 build quality is the best, and the Daimler trim level matches the engine’s character. But for most buyers, the 4.2 six is more than sufficient and dramatically cheaper to own.

What should I take to an inspection?

• Magnet, to check for body filler. Run it over the sills, wheel arches, and any area that looks suspiciously smooth.
• Screwdriver, to poke at suspect metalwork, especially sills and floor edges.
• Torch, to inspect underneath, inside wheel arches, and the boot floor.
• A friend, to check the lights, indicators, and brake lights while you operate the controls.
• Overalls, you’re going underneath the car. Dress accordingly.
• The JDCA buying guide, if available, print the relevant checklist and work through it methodically.

Start with the body. If the sills and floors are rotten, nothing else matters, walk away. Then check the engine (oil leaks, cooling system, smoke), gearbox (smooth shifts, no slipping), and electrics (everything should work). Interior condition indicates overall care.

Ask for service history. Ask about specialists the car has been serviced at. Ask what’s been done recently. A seller who can answer these questions confidently is a better bet than one who bought it last month at auction.

Is the XJ6 a good first classic?

One of the best, particularly the Series 3. The car is comfortable enough for regular use, mechanically straightforward for a competent home mechanic, and supported by an outstanding parts supply and knowledge base. The JDCA provides a safety net of experienced owners who’ll help with any question.

The caveats: you need to be comfortable with the idea that old cars need regular attention, that fuel costs more than a modern car, and that unexpected issues will arise. If you expect modern car reliability, you’ll be disappointed. If you accept that classics require involvement and reward it with character, the XJ6 is brilliant.

Buy a Series 3 4.2 in the best condition you can afford. Join the JDCA. Find a good specialist. Learn to do the basic maintenance yourself (oil changes, spark plugs, filters). And enjoy one of the finest saloon cars ever made.

What modifications are recommended?

Essential (all series):

• Electronic ignition conversion (Pertronix or similar), Series 1 and 2 especially
• Cooling system refresh, upgraded radiator, fresh hoses, electric fan upgrade
• Modern tyres, radial replacements are available and transform handling

Worthwhile:

• Polyurethane suspension bushes, better durability and feel than worn rubber
• Stainless steel exhaust, lasts longer than mild steel, sounds good
• LED interior lighting, brighter, lower current draw
• Bluetooth stereo conversion, keep the original fascia, add modern connectivity

Leave alone:

• The exterior, originality matters for value and aesthetics
• Engine specification, a stock 4.2 is the right engine for an XJ6
• Automatic gearbox, the TH400 doesn’t need improving

Keep all original parts if you modify. Reversibility protects value and gives you the option to return to standard specification if your priorities change.