Daimler XJ40

Which Daimler XJ40 version to buy

There is no later generation to wait for: every XJ40 is 1 generation, Sedan, rear-wheel drive, Gasoline, no boost, front longitudinal engine, 81 L tank, 180 mm ground clearance. The choice is only among 3.6 AT (185 hp), 3.6 AT (202 hp), 4.0 MT, 4.0 AT, and 6.0 AT.

There is no later generation to wait for: every XJ40 is 1 generation, Sedan, rear-wheel drive, Gasoline, no boost, front longitudinal engine, 81 L tank, 180 mm ground clearance. The choice is only among 3.6 AT (185 hp), 3.6 AT (202 hp), 4.0 MT, 4.0 AT, and 6.0 AT.

Power spans 185 hp to 311 hp (126 hp, +68% from the weakest to the strongest). Kerb weight, where measured, spans 1770 kg to 2160 kg (390 kg). Specific output is 51.4 hp/L on 3.6 AT 185 hp (185 ÷ 3.596), 56.2 hp/L on 3.6 AT 202 hp (202 ÷ 3.596), 55.5 hp/L on both 4.0 MT and 4.0 AT (222 ÷ 3.998), and 51.9 hp/L on 6.0 AT (311 ÷ 5.992). The 202 hp 3.6 AT is the densest engine; the 6.0 L twelve does not buy more power per litre.

Mass per horsepower, where kerb weight is measured: 3.6 AT 185 hp is 11.68 kg/hp (2160 ÷ 185); 3.6 AT 202 hp is 8.76 kg/hp (1770 ÷ 202); 4.0 MT is 8.42 kg/hp (1870 ÷ 222); 6.0 AT is 6.17 kg/hp (1920 ÷ 311). 4.0 AT kerb weight is not measured, so its kg/hp cannot be stated.

If the question is “which version to buy,” the catalogue numbers point to three answers, not one: 3.6 AT 202 hp for the lightest car and the only timed 0–100; 4.0 MT if a Manual 5-speed is the point; 6.0 AT if peak power and torque matter more than litres and fuel grade.

XJ40 specs: five versions, one generation

All five sit in the same 1986–1994 window. Restyling is not a separate generation here. What changes is injection, gearbox, cylinders, and mass.

Engine feed: 3.6 AT 185 hp is Central injection (single-point or single- point); the other four are Distributed injection (multi-point). Compression is 9.6 on 3.6 AT 202 hp, 11 on 6.0 AT, not measured on the rest. Bore × stroke is 91 × 92 on 3.6 AT 202 hp, 90 × 78.5 on 6.0 AT, not measured elsewhere. Valves per cylinder are 2 on both 3.6 AT versions and not measured on the 4.0 and 6.0 cars.

3.6 AT 185 hp vs 3.6 AT 202 hp

Same name, same 3596 cc, same 6 Inline, same 2 valves per cylinder, same 92 fuel, same RWD, same Independent, spring suspension, same Ventilated disc front and Disc rear. The buy decision is not “3.6 or not 3.6”; it is which of the two 3.6 AT cars.

The 202 hp car has 17 hp more (+9.2%) and 13 kW more (149 vs 136). Torque is 302 Nm vs 297 Nm (+5 Nm, +1.7%), but the 185 hp peak is at 2500 rpm and the 202 hp peak is at 4000 rpm; rpm for the 185 hp power figure is not measured, while the 202 hp engine is rated at 5250 rpm.

Gearbox: Automatic 3 vs Automatic 4. Injection: Central injection (single-point or single- point) vs Distributed injection (multi-point). Kerb weight: 2160 kg vs 1770 kg — the 185 hp car is 390 kg heavier (+22%). Gross weight is not measured on the 185 hp car and 2190 kg on the 202 hp car. That 2190 kg is only 30 kg above the 185 hp car’s kerb weight, which is why the 185 hp 3.6 AT looks like the wrong buy if you care about mass: 11.68 kg/hp versus 8.76 kg/hp.

Fuel use is measured only on 3.6 AT 185 hp: 24.1 city, 14.8 highway, 19.2 mixed. On 3.6 AT 202 hp those three figures are not measured. Do not treat the heavier car as “the thirsty one” from the table; it is the only one with a printed mpg-style figure.

Performance: 0–100 is 7.9 s and top speed is 219 only on 3.6 AT 202 hp. Both are not measured on 3.6 AT 185 hp. For a timed sprint and a stated top speed, the 202 hp 3.6 AT is the only 3.6 that qualifies.

4.0 MT vs 4.0 AT: same 222 hp, different gearbox

4.0 MT and 4.0 AT share 222 hp, 163 kW, 3998 cc, Gasoline, 6 Inline, No boost, Front, longitudinal, Distributed injection (multi-point), 92 fuel, RWD. Torque, torque rpm, power rpm, compression, bore × stroke, valves per cylinder, 0–100, top speed, city/highway/mixed use, and gross weight are not measured on either.

Displacement is 402 cc above the 3596 cars (+11.2%). Power is 20 hp above the 202 hp 3.6 AT (+9.9%) and 37 hp above the 185 hp 3.6 AT (+20.0%). Specific output (55.5 hp/L) sits between the two 3.6 figures and above 6.0 AT.

The split is the gearbox: Manual 5 versus Automatic 4. 4.0 MT kerb weight is 1870 kg — 100 kg above 3.6 AT 202 hp and 290 kg below 3.6 AT 185 hp. 4.0 AT kerb weight is not measured; you cannot claim it is lighter or heavier than the Manual. If you want the 3998 cc six with a documented kerb weight, 4.0 MT is the one that has it. If you want Automatic 4 with 222 hp, 4.0 AT matches 3.6 AT 202 hp and 6.0 AT on gear count, but without a measured mass.

6.0 AT: what the extra displacement buys

6.0 AT is the only 12 V-shaped engine and the only 95-fuel car. Displacement is 5992 cc: +1994 cc vs the 4.0 cars (+49.9%) and +2396 cc vs the 3.6 cars (+66.6%). Power is 311 hp / 229 kW at 5350 rpm: +89 hp vs 4.0 MT/4.0 AT (+40.1%), +109 hp vs 3.6 AT 202 hp (+54.0%), +126 hp vs 3.6 AT 185 hp (+68.1%). Torque is 477 Nm at 2850 rpm: +175 Nm vs 3.6 AT 202 hp (+58.0%) and +180 Nm vs 3.6 AT 185 hp (+60.6%). Torque on both 4.0 versions is not measured, so those gaps cannot be written.

Compression 11 versus 9.6 on 3.6 AT 202 hp is +1.4. Kerb weight 1920 kg is 150 kg above 3.6 AT 202 hp, 50 kg above 4.0 MT, and 240 kg below 3.6 AT 185 hp. At 6.17 kg/hp it is the lightest per horsepower of the four weighed cars. 0–100, top speed, and all three consumption figures are not measured. Tank remains 81 L, so range cannot be calculated from catalogue fuel use.

What the extra capacity does not buy: a different drive (still RWD), boost (still No), body (still Sedan), clearance (still 180 mm), or a later generation. It buys cylinders (12 vs 6), layout (V-shaped vs Inline), fuel 95 vs 92, and the highest hp and Nm in the set.

Performance and economy (mpg)

Measured 0–100 exists for one row: 3.6 AT 202 hp at 7.9 s. Not measured: 3.6 AT 185 hp, 4.0 MT, 4.0 AT, 6.0 AT.

Measured top speed exists for one row: 3.6 AT 202 hp at 219. Not measured on the other four.

Measured consumption exists for one row: 3.6 AT 185 hp at 24.1 / 14.8 / 19.2 (city / highway / mixed). Not measured on the other four. Highway versus city on that car is 9.3 units less on the highway (24.1 − 14.8). Mixed sits 4.4 above highway and 4.9 below city.

CO2 and eco class are not measured on every version.

Buy implication: you cannot pick a “most economical” XJ40 from a full table. You can only say the 185 hp 3.6 AT is the one with printed use, and it is also the heaviest kerb (2160 kg).

Dimensions, weight, tank, wheels

Ground clearance is 180 mm on all five. Tank is 81 L on all five. Wheel sizes are not measured on all five.

Kerb weight: 3.6 AT 185 hp 2160 kg; 3.6 AT 202 hp 1770 kg; 4.0 MT 1870 kg; 4.0 AT not measured; 6.0 AT 1920 kg. Gross: only 3.6 AT 202 hp at 2190 kg; payload on that car is 420 kg (2190 − 1770). Gross on the other four is not measured.

Front suspension Independent, spring and rear Independent, spring on all five. Front brakes Ventilated disc, rear Disc, all five.

Weight is the sharpest chassis difference in the file: 390 kg between the two 3.6 AT cars. That gap is larger than 6.0 AT versus 3.6 AT 202 hp (150 kg) and larger than 4.0 MT versus 3.6 AT 202 hp (100 kg).

Reliability and problems: what the numbers do and do not say

The data do not list faults, recall counts, or service intervals. Reliability talk from this file is limited to configuration spread: two injection types on the 3.6 Automatics, 3-speed versus 4-speed Automatic, one Manual 5, 6 versus 12 cylinders, 92 versus 95 fuel. More parts in the 12 V-shaped 6.0 AT is a parts-count fact (12 vs 6), not a failure-rate fact. Central injection (single-point or single- point) on 3.6 AT 185 hp versus Distributed injection (multi-point) on the rest is a hardware split, not a verdict on which lasts longer.

Which version to choose

Buy 3.6 AT 202 hp if you want the lowest measured kerb (1770 kg), the only 0–100 (7.9) and top speed (219), Automatic 4, Distributed injection (multi-point), and the highest hp/L (56.2). Versus the other 3.6 AT you give up the only printed consumption figures and pick up 17 hp and lose 390 kg.

Do not buy 3.6 AT 185 hp for lightness or a timed sprint. It is the heaviest (2160 kg), Automatic 3, Central injection (single-point or single- point), 185 hp, and 0–100 / top speed not measured. Buy it only if you specifically want that 3-speed Automatic and the only city/highway/mixed numbers in the catalogue (24.1 / 14.8 / 19.2).

Buy 4.0 MT if the Manual 5 is the requirement. You get 222 hp from 3998 cc at 1870 kg (8.42 kg/hp). Torque, 0–100, top speed, and mpg are not measured. Versus 3.6 AT 202 hp: +20 hp, +100 kg, +402 cc, no timed performance.

Buy 4.0 AT if you want 222 hp with Automatic 4 and do not need a measured kerb weight. Versus 4.0 MT the engine figures that exist are identical; the gearbox is the difference. Versus 3.6 AT 202 hp you gain 20 hp and 402 cc and lose the only 7.9 s / 219 figures.

Buy 6.0 AT if 311 hp and 477 Nm matter more than litres and 95 fuel. You pay 1994 cc over the 4.0 cars and 12 V-shaped cylinders instead of 6 Inline. kg/hp is the best measured (6.17). 0–100, top speed, and mpg are not measured. Versus 3.6 AT 202 hp: +109 hp, +175 Nm, +150 kg, fuel 95 instead of 92.

There is no second generation to “wait for a facelift car.” The arithmetic on this one generation is: lightest and only timed car = 3.6 AT 202 hp; only Manual = 4.0 MT; most hp and Nm = 6.0 AT; only printed mpg = 3.6 AT 185 hp; 4.0 AT is the 222 hp Automatic whose weight was not measured.