The Jaguar Mk IX  1958-1961

Years MK IX 1958-1961
See also MK VII   MK VIII
Notes The MK IX was Introduced at the Earls Court London motor show in the fall of 1958. Visually it was almost identical to its predecessor the MK VIII. Mechanically however much was updated. Under the hood the engine capacity was increased to 3.8 liters by the adotion of the 3.8 version of the XK engine. This was achieved by increasing the stroke from 83mm to 87mm and using a slightly taller block. The existing "B" type cylinder head was retained as fitted to the 3.4 engine in the MK VIII.  This engine went on to be fitted to the XK150 sports car the following year in both standard, and uprated "S" state of tune.

The previous braking system was upgraded to Dunlop 4 wheel disc system, and power steering was made available as a standard fitment. This system had debuted in late models of the MK VIII. It was driven by a Hobourn Eaton pump driven by a take-off at the rear of the dynamo.

Nothing much changed inside the car, as the MK VIII was already superbly equipped. The major change was the up-rating of the heater system which had been criticized as being marginal,

As with the MK VIII the majority of MK IX's were sold with a dual color scheme, darker color on top.

As mentioned in the section on the MK VIII, production of the low volume  MK VIIIB continued throughout the life of the MK IX 

Description 4 door sedan (saloon), separate chassis
Colors See the large sedans colors page
Additional Pictures

We are grateful to Docs Jags for their kind permission to use selected images in this database


1959 Jaguar MK IX sedan
Mark9.jpg (15155 bytes)

courtesy Benedikt Lehner and his brother-in-law Chris Vellender who  restored it.
Note one piece windshield, chrome surround to radiator grille, and the Jaguar leaper. Also cut-outs in rear wheel spats.

Model Engine Bore/Stroke Power
MK IX 3781cc 6 cyl twin ohc 87 x 106 mm 220 bhp @ 5500 rpm
SU 1/3/4 inch HD6
Engines is enlarged 3.8 version of the XK engine
Brakes Four wheel discs, servo assist (Dunlop)
(Various sources differ, slightly)
MK IX  (RHD)  5984 Total 10005
MK IX  (LHD)  4021
MK IX 3950 pounds
Length 16 feet 4 1/2 inches
Height 5 feet 3 inches 
Width 6 feet 1 inches 
Top speed 115 mph  
Wheelbase 120 inches
Transmission 4-speed manual.  optional  Borg and Warner 3 speed automatic transmission. Laycock de Normanville overdrive fitted on the standard transmission car.
Front Independent. wishbones and torsion bar, anti roll bar
Rear Live axle, half elliptic leaf springs.
Chassis Numbers BW Suffix indicates fitment of Borg Warner automatic transmission
DN Prefix indicates firment of overdrive (De Normanville)
MK IX Sedan 770001 and up - Right hand drive
790001 and up - Left hand drive
Standard Equipment Leather seats, fog/spot lights.Hub caps, sun roof, disc brakes,power assisted steering.
Options Two tone paint colors
Notes According to Larry Martz the tachometer changed from mechanical to electric operation at chassis numbers 771820 RHD and 791072 LHD.  Larry maintains the MK IX registry