There's plenty of choice when it comes to the Series III, and here's how to pick the very best...
When introduced in 1979, the Jaguar XJ6 Series III was not immediately to everyone's liking. Despite an expensive redesign with its Pininfarina styled roof, and refreshed cabin, some Big Cat enthusiasts felt that it was taking liberties with the classic looks of one of their favourites. In fact, the Series III set out to rectify some of the deficiencies of the Series II, and was better equipped for everyday use, but you had to try one to find that out. In addition to new body panels, the new model had an increased amount of glass, and a much-needed additional 3in of headroom in the back - great if you're being chauffered! External differences included flush door handles, vertical grille bars, revised 'Gothic' rear lamp clusters, and impact bumpers with decorative chrone along their top edges. There were three engine options to choose from, 3.4- and 4.2-litre straight sixes and V12 5.3-litre. The 4.2 had the advantage of fuel injection, while the 3.4- and 4.2- litre cars both had the option of the LT77 five-speed manual gearbox.
VITAL STATISTICS
Engine: 4235cc/6-cyl/DOHC
Power: 205bhp@5000rpm
Torque: 236lb ft@3750rpm
Maximum speed: 130mph
0-60mph: 8.5sec
Fuel consumption: 16-20mpg
Transmission: RWD, five-speed manual/three-speed auto
WHAT TO LOOK FOR
Rotten luck
While these cars are known for being well built, rot free they are not. One of the first areas where rust attacks the bodywork is beneath the rear valance where the exhausts emerge. Check the boot floor too. A really crucial area to inspect is where the rear suspension radius arms are mounted to the floorpan near the rear doors. Water can infiltrate the double-skinned rear valance and if the rubber is slack around the front and rear windscreens, it can get in and cause damage to the surrounding areas. If mudflaps are fitted, lift them to inspect the state of the wheelarches. Light corrosion shouldn't put you off, but extensive amounts of rust will inevitably result in big bills. Keep looking.
Six of the best
Six-cylinder engines are tough and can rack up six-figure mileages easily with good maintenance. Head gaskets should be replaced at 100,000 miles so check if this has been done. While V12 engines are also generally robust, they are not cheap to fix so if you find a troublesome one, move on. They are less DIY-friendly than the 3.4- and 4.2-litre engines too.
Cool running
If you are looking at a fuel injected car, make sure that you hear the engine running up from cold, building it up to correct temperature. If you arrive and the 'helpful' owner already has the engine running, ask him to turn it off and start again when it has cooled down.
Under pressure
Good oil pressure is essential and should be at least 40psi when you start up from cold and not fall below 20psi once it has warmed up. Gauges may not be reliable.
Top gear
Gearboxes - the Rover SD1-derived five-speed manual and a three-speed auto - can be troublesome. Other worthwhile checks are for worn brake discs, noisy timing chains and rear axles, plus fuel hoses on fuel injected cars.
Heat treatment
Make sure the climate control equipment is working properly as this can be another area where you'd have to carefully evaluate the cost of work or replacement.
You wear it well
That 'gentleman's club' feel of the cab interior is wonderful and the leather seats and door trim generally wear well and respond to being looked after, which is good as they can be expensive to retrim. The cost of making a car like this look right can easily exceed that of mechanical considerations.
OUR VERDICT
After early doubts were allayed, the Series III established itself as one of the best Jaguars of all, with the injected 4.2-litre coming out as the pick of the crop. As the Series III was produced in large numbers, the survival rate has been good. If you are interested, don't leap at the first one you see but keep looking until you're sure you have the car you want. In its review of June 1980, Car and Driver magazine described the Series III sa being as 'slick as the inside of Faye Dunaway's dressing gown' - and you can't be fairer than that!
MANUAL 
LHD
