Infiniti FX: Which Version to Buy and Why
Choosing an Infiniti FX comes down to four priorities. The 3.0 AT is the economy choice, combining 238 hp and 550 Nm with the lowest listed combined consumption of 9 l/100 km. The later 3.7 AT versions offer a stronger performance-to-consumption balance, reaching 0–100 km/h in 6.8 seconds while using 12.2 l/100 km combined.
Choosing an Infiniti FX comes down to four priorities. The 3.0 AT is the economy choice, combining 238 hp and 550 Nm with the lowest listed combined consumption of 9 l/100 km. The later 3.7 AT versions offer a stronger performance-to-consumption balance, reaching 0–100 km/h in 6.8 seconds while using 12.2 l/100 km combined. The 5.0 AT is the performance option, with as much as 420 hp, a 5.6-second acceleration time and a 300 km/h maximum speed. Buyers considering the earlier generation can choose the 3.5 AT for lower consumption or the 4.5 AT for V8 performance. Every FX listed here is an SUV 5-doors with a 90-litre tank.
Infiniti FX generations: what changed?
The first generation ran from 2002 to 2006 and included three listed versions, all with a 5-speed Automatic. Its 3.5 AT was offered with RWD or AWD, while the 4.5 AT used AWD. All three had 195 mm of ground clearance.
The first-generation restyling covered 2006–2009 and also contained three listed versions. The 3.5 AT again appeared with both AWD and RWD, while the 4.5 AT retained AWD. Output for the restyled 4.5 AT rose from 315 hp to 328 hp, and its 0–100 km/h time changed from 6.3 to 6.8 seconds. All versions continued with a 5-speed Automatic and 195 mm of clearance.
The second generation ran from 2008 to 2012 with five listed versions. Every version used AWD and a 7-speed Automatic. The engine range expanded to 3.0 AT, 3.5 AT, 3.7 AT and two 5.0 AT specifications distinguished by 390 hp and 400 hp. Ground clearance was 184 mm throughout the listed range.
The second-generation restyling ran from 2011 to 2013 and had five listed versions: 3.0 AT, two 3.7 AT specifications distinguished by 315 hp and 333 hp, and two 5.0 AT specifications distinguished by 400 hp and 420 hp. All retained AWD and a 7-speed Automatic. Most had 184 mm of clearance, while the 420 hp 5.0 AT had 164 mm.
Infiniti FX engine specs
| Generation and version | Power | Torque | Displacement | Fuel | Cylinders/layout | Boost | Gearbox | Drive |
|---|---|---|---|---|---|---|---|---|
| First generation 3.5 AT, RWD | 280 hp | 366 Nm | 3498 cc | Gasoline | 6, V-shaped | No | 5-speed Automatic | RWD |
| First generation 3.5 AT, AWD | 280 hp | 366 Nm | 3498 cc | Gasoline | 6, V-shaped | No | 5-speed Automatic | AWD |
| First generation 4.5 AT | 315 hp | 466 Nm | 4494 cc | Gasoline | 8, V-shaped | No | 5-speed Automatic | AWD |
| First-generation restyling 3.5 AT, AWD | 280 hp | 363 Nm | 3498 cc | Gasoline | 6, V-shaped | No | 5-speed Automatic | AWD |
| First-generation restyling 4.5 AT | 328 hp | 466 Nm | 4494 cc | Gasoline | 8, V-shaped | No | 5-speed Automatic | AWD |
| First-generation restyling 3.5 AT, RWD | 280 hp | 363 Nm | 3498 cc | Gasoline | 6, V-shaped | No | 5-speed Automatic | RWD |
| Second generation 5.0 AT, 400 hp | 400 hp | 500 Nm | 5026 cc | Gasoline | 8, V-shaped | No | 7-speed Automatic | AWD |
| Second generation 3.5 AT | 307 hp | 355 Nm | 3498 cc | Gasoline | 6, V-shaped | No | 7-speed Automatic | AWD |
| Second generation 3.0 AT | 238 hp | 550 Nm | 2993 cc | Diesel | 6, V-shaped | Turbo | 7-speed Automatic | AWD |
| Second generation 3.7 AT | 320 hp | 367 Nm | 3696 cc | Gasoline | 6, V-shaped | No | 7-speed Automatic | AWD |
| Second generation 5.0 AT, 390 hp | 390 hp | 500 Nm | 5026 cc | Gasoline | 8, V-shaped | No | 7-speed Automatic | AWD |
| Second-generation restyling 5.0 AT, 400 hp | 400 hp | 500 Nm | 5026 cc | Gasoline | 8, V-shaped | No | 7-speed Automatic | AWD |
| Second-generation restyling 5.0 AT, 420 hp | 420 hp | 500 Nm | 5026 cc | Gasoline | 8, V-shaped | No | 7-speed Automatic | AWD |
| Second-generation restyling 3.0 AT | 238 hp | 550 Nm | 2993 cc | Diesel | 6, V-shaped | Turbo | 7-speed Automatic | AWD |
| Second-generation restyling 3.7 AT, 333 hp | 333 hp | 363 Nm | 3696 cc | Gasoline | 6, V-shaped | No | 7-speed Automatic | AWD |
| Second-generation restyling 3.7 AT, 315 hp | 315 hp | 363 Nm | 3696 cc | Gasoline | 6, V-shaped | No | 7-speed Automatic | AWD |
The 3.0 AT produces about 79.5 hp per litre and the 420 hp 5.0 AT about 83.6 hp per litre. The strongest listed specific output belongs to the 333 hp 3.7 AT, at about 90.1 hp per litre. Its 315 hp counterpart produces about 85.2 hp per litre, despite sharing the same displacement and 363 Nm torque figure.
Infiniti FX performance and fuel economy
| Generation and version | 0–100 km/h | Top speed | City | Highway | Combined |
|---|---|---|---|---|---|
| First generation 3.5 AT, RWD | 7.1 sec | 221 km/h | 13.9 l/100 km | 10.2 l/100 km | 11.5 l/100 km |
| First generation 3.5 AT, AWD | 7.4 sec | 221 km/h | 14.7 l/100 km | 10.7 l/100 km | 12 l/100 km |
| First generation 4.5 AT | 6.3 sec | 225 km/h | 15.7 l/100 km | 12.4 l/100 km | 13.5 l/100 km |
| Restyled first generation 3.5 AT, AWD | 7.8 sec | 212 km/h | 14.7 l/100 km | 10.7 l/100 km | 12.6 l/100 km |
| Restyled first generation 4.5 AT | 6.8 sec | 228 km/h | 15.7 l/100 km | 12.4 l/100 km | 14 l/100 km |
| Restyled first generation 3.5 AT, RWD | 7.8 sec | 212 km/h | 18.2 l/100 km | 11 l/100 km | 13.6 l/100 km |
| Second generation 5.0 AT, 400 hp | 5.8 sec | 250 km/h | 18.8 l/100 km | 9.8 l/100 km | 13.1 l/100 km |
| Second generation 3.5 AT | 6.9 sec | 228 km/h | 16.6 l/100 km | 9 l/100 km | 11.8 l/100 km |
| Second generation 3.0 AT | 8.3 sec | 212 km/h | 11.2 l/100 km | 7.8 l/100 km | 9 l/100 km |
| Second generation 3.7 AT | 6.8 sec | 233 km/h | 17.1 l/100 km | 9.4 l/100 km | 12.2 l/100 km |
| Second generation 5.0 AT, 390 hp | 5.8 sec | 250 km/h | 18.3 l/100 km | 9.6 l/100 km | 12.8 l/100 km |
| Restyled second generation 5.0 AT, 400 hp | 5.8 sec | 250 km/h | 18.8 l/100 km | 9.8 l/100 km | 13.1 l/100 km |
| Restyled second generation 5.0 AT, 420 hp | 5.6 sec | 300 km/h | 18.3 l/100 km | 9.6 l/100 km | 12.8 l/100 km |
| Restyled second generation 3.0 AT | 8.3 sec | 212 km/h | 11.2 l/100 km | 7.8 l/100 km | 9 l/100 km |
| Restyled second generation 3.7 AT, 333 hp | 6.8 sec | 233 km/h | 17.1 l/100 km | 9.4 l/100 km | 12.2 l/100 km |
| Restyled second generation 3.7 AT, 315 hp | 6.8 sec | 233 km/h | 17.1 l/100 km | 9.4 l/100 km | 12.2 l/100 km |
No listed acceleration, maximum-speed or consumption figure is unmeasured. Among second-generation choices, the 3.0 AT consumes 3.2 l/100 km less than the 3.7 AT in combined driving but takes 1.5 seconds longer to reach 100 km/h. The restyled 420 hp 5.0 AT is 0.2 seconds quicker than the 400 hp version, has a 50 km/h higher maximum speed and uses 0.3 l/100 km less combined fuel.
Infiniti FX weight, clearance and wheel specs
| Generation and version | Kerb weight | Gross weight | Clearance | Tank | Wheels |
|---|---|---|---|---|---|
| First generation 3.5 AT, RWD | 1840 kg | 2340 kg | 195 mm | 90 l | not measured |
| First generation 3.5 AT, AWD | 1900 kg | 2430 kg | 195 mm | 90 l | not measured |
| First generation 4.5 AT | 2005 kg | 2478 kg | 195 mm | 90 l | not measured |
| Restyled first generation 3.5 AT, AWD | 1900 kg | 2422 kg | 195 mm | 90 l | 265/60 R18; 265/50 R20 |
| Restyled first generation 4.5 AT | 1917 kg | 2446 kg | 195 mm | 90 l | 265/60 R18; 265/50 R20 |
| Restyled first generation 3.5 AT, RWD | 1890 kg | 2342 kg | 195 mm | 90 l | 265/60 R18; 265/50 R20 |
| Second generation 5.0 AT, 400 hp | 2098 kg | 2320 kg | 184 mm | 90 l | not measured |
| Second generation 3.5 AT | 1953 kg | 2240 kg | 184 mm | 90 l | not measured |
| Second generation 3.0 AT | 2080 kg | 2749 kg | 184 mm | 90 l | not measured |
| Second generation 3.7 AT | 2010 kg | 2500 kg | 184 mm | 90 l | 265/50 R20; 265/45 R21 |
| Second generation 5.0 AT, 390 hp | 2098 kg | 2320 kg | 184 mm | 90 l | not measured |
| Restyled second generation 5.0 AT, 400 hp | 2098 kg | 2320 kg | 184 mm | 90 l | not measured |
| Restyled second generation 5.0 AT, 420 hp | 2098 kg | 2320 kg | 164 mm | 90 l | not measured |
| Restyled second generation 3.0 AT | 2080 kg | 2749 kg | 184 mm | 90 l | not measured |
| Restyled second generation 3.7 AT, 333 hp | 2010 kg | 2500 kg | 184 mm | 90 l | 265/50 R20; 265/45 R21 |
| Restyled second generation 3.7 AT, 315 hp | 2010 kg | 2500 kg | 184 mm | 90 l | 265/50 R20; 265/45 R21 |
Overall exterior dimensions are not measured in the supplied data. On weight per horsepower, the restyled 420 hp 5.0 AT leads at about 5.0 kg/hp. The 333 hp 3.7 AT follows at about 6.0 kg/hp, while the 3.0 AT carries about 8.7 kg/hp. The first-generation RWD 3.5 AT is 60 kg lighter than its AWD counterpart and uses 0.5 l/100 km less combined fuel.
Which Infiniti FX version should you buy?
Choose the 3.0 AT when consumption and torque matter most. Its 550 Nm is the highest torque figure in the range, exceeding either 5.0 AT specification by 50 Nm, while its 9 l/100 km combined consumption is the lowest listed. The trade-off is the slowest acceleration at 8.3 seconds.
Choose a 3.7 AT for the middle ground. The 333 hp restyled version gives the best power per litre in the data, reaches 100 km/h in 6.8 seconds and consumes 12.2 l/100 km combined. The restyled 315 hp 3.7 AT records exactly the same 363 Nm, acceleration, maximum speed and consumption, so the data gives the 333 hp version an 18 hp advantage with no measured performance or economy penalty.
Choose the restyled 420 hp 5.0 AT for maximum performance. Compared with the restyled 333 hp 3.7 AT, it adds 87 hp and 137 Nm, cuts the acceleration time by 1.2 seconds and raises maximum speed by 67 km/h. Combined consumption rises by only 0.6 l/100 km, but clearance falls by 20 mm.
Among early cars, the first-generation RWD 3.5 AT is the consumption-focused selection, while the original 4.5 AT is the performance choice. Moving from that 3.5 AT to the 4.5 AT adds 35 hp and 100 Nm and cuts 0–100 km/h from 7.1 to 6.3 seconds, at the cost of 2 l/100 km more combined fuel and 165 kg more kerb weight. No purchase prices, reliability measurements, problem records or sale listings are provided, so those factors cannot be compared from this data.