The Jaguar Mk X  and 420G 1961-1970

Both these new models had some pieces of their design in common - both featured the triple 2 inch carburetored version of Jaguars new 3.8 XK engine, as had been fitted to the XK150 "S" , both had monococqe bodies, replacing the previous models body on chassis construction, and both featured Jaguars new design independent rear suspension mounted in a separate sub-frame, which it turned out was still being used 25 years later in the XJ6.

There the similarities between E Type and MK X ended. The MK X was a massive car meauring 16 feet 10 inches which was almost 6 inches longer than its predecessor the MK IX (and about  22 inches longer than the contemporary MK II). It was also extremely wide, at 6 feet 4 inces.  The only dimemsion which was reduced when compared to the MK IX was the height, which was reduced from 5 feet 3 inches  to 4 feet 6 3/4 inches. Some of this reduction was due to the adoption of 14 inch wheels, rather than 15 inch.

Being longer and lower the MK X 's bulk was quite well disguised, and apart from the somewhat bulging sides, the car looked quite sleek.  The car retained some of the styling cues of the "big" Jaguars. The chome plated window frames, and the imposing radiator, which was now sloped forward to reduce the height at the front. For the first time on a Jaguar a 4 headlight treatment was used.and the traditional Jaguar horn grilles were retained. Power assisted steering was standard, and the car was availabel with 3 speed Borg Warner automatic transmission, or a 4 speedmanual box. 

Inside the MK X was traditional Jaguar luxury with leather seating, and walnut wood. The dash was the new "corporate" design of the 1960's that had originated with the MK II in 1959, but with much more extensive use of wood. veneer. split bench front seats were used, and the rear seats had individual picnic tables that folded down from the back of the front seats.

The MK X 4.2 was introduced in October 1964 for the 1965 model year, and in general received the same mechanical updates as the contemporary E Type. The engine was further enlarged to 4.2 liters, and the transmission was either the new all synchromatic 4 speed, or a newer design Borg Warner Model 8 automatic. An alternator replaced the generator of the previous model, and power steering and braking systems were improved. Air conditioning became available as an option in 1966.

For the 1967 model year the designarion was changed from MK X to 420G.  This was in line with the model policy at the time, when all Jaguars models were being rationalized.  The MK II range became the 240 and the 340, and the new 420 was introduced as an intermediate model between the MK II and the MK X. The changes to the MK X were cosmetic only, but quite distinctive. Most noticeable were the radiator grille which was given a distinctive central vertical bar, side repeater flashers, and a new hub cap design. In addition the car became available with two tone paint finishes, or, when   painted in a single color, a chrome strip down the waist line was employed, where the divider line would have been for two colors. Inside the car, crash proofing was improved by fitting a black padding to the top of the dashboard, and the clock was moved from its position in the rev-counter, to a separate fitment in the top crashproofing of the dash. Perforated leather was used for the seats.

The 420G became the last survivor of Jaguars extensive 1960's range of cars, all of which were killed off after the launch of the XJ6 in 1968.  Production of the 420G actually continued well into 1970.

courtesy Joel Kimball Ventura, CA

In 1968 with the introduction of the S2 E-Type, the USA version of the same 4.2 engine that was fitted to that car was equipped with two Stromberg carburetors, rather than three SU units. Its not known if the 1968 and up 420G's destined to the States suffered a similar modification.