Jaguar MK X

Buyer Beware

The MkX/420G is a mixture of good and bad news. The former is that because this fat cat provided the mainframe of the Daimler limousines (such as hearses!) right up until 1992, parts and panels are in reasonable supply even from the manufacturers.

Rust has to be the biggest enemy. Start at the fl oorpan and work upwards! Look for signs of serious rot and poor repairs on the fl oor, especially by the front seats, all box sections, jacking points, radiator cross-member and suspension pick-up points.

The MkX shares a good number of cabin parts with other Jags and holds no real worries so long as the hide is in good shape and that forest of a dashboard is okay. Otherwise, you are looking at an expensive restoration job. Some parts, such as those super picnic tables, are particular to the car.

Those massive bumpers should be scrutinised for damage and corrosion because fettling all that chrome will prove expensive.

On such a big car, expect to fi nd tired springs and dampers. The E-type rear end is fi tted with lots of bushes and prone to wear, meaning the subframe needs to be removed – a major job on the driveway.

The disc rear brakes are peculiar to the car being inboard mounted and these can seize, especially the handbrake which – being a Jag – is rarely that effective anyway due to lack of expert use. Also peculiar to this Jaguar are an odd wheel and tyre size (205 x 14). Early XJ6 rims and tyres (15 inch) can be substituted and an okay swap, even if the car rides a tad higher.

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Weighing two tons and the size of a Transit but the MkX was also a better car than a Rolls yet nearly a third of the price when new! They still offer remarkable value and a lot of classic car for the money – or too much flash for your cash?

Essentially there are three derivatives of the MkX, the 3.8, the later 4.2 and then the 420G which saw out the range in 1970. In many ways the Mk X was an E-type albeit clothed in a limo’s bodyshell. The XK engine was lifted directly from the E-type, the triple carburettor engine gave 250-bhp on 8:1 compression ratio (the E-type was 265 with 9:1). The most advanced feature though was the IRS (independent rear suspension), which it also shared in principle with that sports car (and continued in production until the Aston Martin DB7 would you believe). Understandably the big barge, aimed at the American market, featured a Borg Warner automatic gearbox, although the standard Moss four-speed manual ‘box (with or without overdrive) was also offered. The biggest change arrived in 1964 when the lustier if not so sweet 4.2 engine replaced the sportier 3.8. The all-round disc brake set up changed from the rather curious Kelsey-Hayes bellows servo, to a normal vacuum type. Air-conditioning (Delany Galley) and a Jaguar fi rst, electric windows were desirable optional extras. The 420G was an even fl ashier version gaining dashing chrome waistline strips and slightly modifi ed interior featuring a padded dash top. There was even a special limousine version fi tted out with a centre partition, cocktail cabinet and massive picnic tables. Strictly speaking, there was no Daimler version made but you have to remember that the 420G was used as the platform for the Daimler DS420 limousine. Which one to buy? Well, to be honest, condition counts more than anything else and a great 3.8 makes a better bet than feeling blue 4.2 although like-for-like, thelater car is better because apart from that larger engine – which suited the MkX better than the E-type – a better gearbox plus Jaguar’s variable rate Varamatic power steering system replaced the original, lifeless, PAS set up – and there was now an alternator, too. Prices are similar as well which means they are comparative bargains when compared to a Mk1 or Mk2 saloon. Costing a remarkable £2300 when new, values are now similar to the S-type/420 models meaning you can buy a very nice example for under £10,000 and a cracker for double this – and like or loathe the car, that’s a lot of classic metal for your money!

WHICH MODEL FOR YOU?

Essentially there are three derivatives of the MkX, the 3.8, the later 4.2 and then the 420G which saw out the range in 1970. In many ways the Mk X was an E-type albeit clothed in a limo’s bodyshell. The XK engine was lifted directly from the E-type, the triple carburettor engine gave 250-bhp on 8:1 compression ratio (the E-type was 265 with 9:1). The most advanced feature though was the IRS (independent rear suspension), which it also shared in principle with that sports car (and continued in production until the Aston Martin DB7 would you believe). Understandably the big barge, aimed at the American market, featured a Borg Warner automatic gearbox, although the standard Moss four-speed manual ‘box (with or without overdrive) was also offered. The biggest change arrived in 1964 when the lustier if not so sweet 4.2 engine replaced the sportier 3.8. The all-round disc brake set up changed from the rather curious Kelsey-Hayes bellows servo, to a normal vacuum type. Air-conditioning (Delany Galley) and a Jaguar fi rst, electric windows were desirable optional extras. The 420G was an even fl ashier version gaining dashing chrome waistline strips and slightly modifi ed interior featuring a padded dash top. There was even a special limousine version fi tted out with a centre partition, cocktail cabinet and massive picnic tables. Strictly speaking, there was no Daimler version made but you have to remember that the 420G was used as the platform for the Daimler DS420 limousine. Which one to buy? Well, to be honest, condition counts more than anything else and a great 3.8 makes a better bet than feeling blue 4.2 although like-for-like, thelater car is better because apart from that larger engine – which suited the MkX better than the E-type – a better gearbox plus Jaguar’s variable rate Varamatic power steering system replaced the original, lifeless, PAS set up – and there was now an alternator, too. Prices are similar as well which means they are comparative bargains when compared to a Mk1 or Mk2 saloon. Costing a remarkable £2300 when new, values are now similar to the S-type/420 models meaning you can buy a very nice example for under £10,000 and a cracker for double this – and like or loathe the car, that’s a lot of classic metal for your money!

BEHIND THE WHEEL?

Before anything else, let’s talk about the sheer size of the bloody thing! It occupies almost 17 feet and dwarfed even the Rolls- Royce Silver Cloud with its width of 6ft 4in (although a Ford Focus is now almost as wide!), weighing in at a massive 37-cwt. Rear seat space is so great, that they almost occupy another post code. However let’s put this into context so not to put you off. With so many drivers today used to piloting massive 4x4s, a MkX is no longer the culture shock it was half a century ago but still you need a big drive and garage to store one. With its E-type DNA (they were launched months apart) the MkX drives and handles far better than any other big old classic of that era, although it’s no E-type of course! Also the car’s prowess depends on how good the suspension – and that complex IRS in particular – has been maintained. It takes a brave soul to hurl a MkX around but with a maximum speed of over 120mph and a zero to 60 dash in some 10 seconds it will surprise many moderns. Of course, the MkX was designed more for upper class cruising, and in its day was better than a Rolls-Royce.

It still impresses with its magic carpet ride, quietness (unless the engine is revved hard) and immense comfort from that old world Jaguar interior. Best keep any spirited driving as a solo treat!

What won’t be a treat are the regular visits to the garage pumps. Expect 15mpg regardless of how it is driven and less if the old girl is clapped out. It’s a weekend cruiser Those massive bumpers should be scrutinised for damage and corrosion because fettling all that chrome will prove expensive.

On such a big car, expect to find tired springs and dampers. The E-type rear end is fi tted with lots of bushes and prone to wear, meaning the subframe needs to be removed – a major job on the driveway. The disc rear brakes are peculiar to the car being inboard mounted and these can seize, especially the handbrake which – being a Jag – is rarely that effective anyway due to lack of expert use. Also peculiar to this Jaguar are an odd wheel and tyre size (205 x 14). Early XJ6 rims and tyres (15 inch) can be substituted and an okay swap, even if the car rides a tad higher.

DAILY DRIVER?

Hardly! The size and thirst of a MkX means it’s ‘something for the weekend sir’ and even then, the heaviness of the gearbox, unassisted steering and the brakes can be tiring. In standard form the car was a ground breaker back in its heyday but now you may want to modify yours to make it easier to drive.

The curious 14-inch tyres that were special to this Jaguar are still available through Vintage Tyre Services and Longstone Tyres but are expensive making swapping over to the XJ6 15-inch wheels extremely worthwhile as the later car’s 205 VR 70 15 tyres have the same rolling radius as those old ‘balloon’ originals, giving as vastly improved ride and grip without altering the speedo reading.

As the DS420 was built on the MkX platform it effectively means that some of the upgrades can be incorporated into the earlier car such as massive four-pot front brake calipers with their ventilated discs that bolt straight on. It is also possible to fi t the excellent four-speed automatic found in the XJ40 which is a real boon.

Or if you are feeling brave then fit a V12 as Jaguar did during development! In May 1960 Jaguar bought the Daimler company and with it came the outfi t’s two fi ne V8 engines. The 4.5 lump was tried in the MkX giving a useful gain in performance, achieving some 133mph at MIRA as well as slicing the 0-60mph down to E-type levels! The more pragmatic owner will fi t more straightforward upgrades such as electronic ignition, a larger, more effi cient radiator and perhaps S3 E-type brakes along with new (GAZ, Spaz or Koni ) dampers and re-bush the IRS (a time consuming and expensive job but one that really pays dividends), all of which will make a very nice car indeed.

OWNING AND RUNNING?

Don’t let the size of the thing put you off because a MkX won’t cost any more than a Mk2 to maintain. Mechanical parts are common on other Jags, of course, and while body parts aren’t now so plentiful, the DS420 limo carried on in production until the early 1990s so in theory certain body parts (floor, front end) should be obtainable.