Vehicle overview
The latest Buick is built at the same General Motors plant that also produces the 2006 Cadillac DTS, which is an upgraded version of the outgoing DeVille. The cars run on the same wheelbase length, although the Buick Lucerne is about 4 inches shorter. The Lucerne's relationship with the DTS is particularly favorable for the powertrain. After a drought of about a decade, the V8 engine is finding its way back into the Buick lineup. The 4.6-liter Northstar DOHC V8 is available in CXL trim and standard in CXS. It produces 275 and 290 lb-ft of torque. As the base engine for the CX and CXL, Buick offers General Motors' proven 3.8-liter V6 OHV. This makes 197 hp and 227 Nm of torque.

Buick has styled the Lucerne with a sleek and attractive exterior. It's not overly exciting, but the rear end resembles that of the 2006 Passat, and the portholes in the front wings are a subtle reference to Buick cars of the past (V6 models have three portholes, V8 models have four). On the road, the Buick Lucerne is particularly quiet thanks to the "QuietTuning" initiative, which includes special technical modifications to reduce road, engine and wind noise. Ride quality is soft, while handling is unexpectedly smooth for a large Buick. However, the Lucerne performs poorly in several unexpected areas. Standard equipment is more than adequate, but typical luxuries such as one-touch windows, a folding rear bench seat and a retractable steering wheel or electrically adjustable pedals are not available. Also absent are HID headlights, adaptive cruise control and wireless Bluetooth.

Performance and consumption
Two engines are available for the Buick Lucerne model. The Trim CX comes with a 3.8-liter V6 that produces 197 hp and 227 lb-ft. Available in the CXL and standard in the CXS is a 4.6-liter V8. It produces 275 hp and 290 Nm of torque. Both engines send their power to the front wheels via a four-speed automatic transmission.

Standard safety equipment includes OnStar, four-wheel-lock brakes, traction control, front side airbags and curtain airbags to protect the heads of all outboard passengers. Stability control and BrakeAssist are standard on the CXS, an option for V8-powered CXL models and not available on V6-powered models. Lucerne front seats have a two-point seat belt for the middle position. In NHTSA crash tests, the Buick Lucerne received five stars (out of a possible five) for driver and passenger protection in frontal crashes. Four stars were awarded for front and rear passenger protection in side impacts.

A soft, smooth ride is a priority in the 2006 Buick Lucerne. The mildly tuned CX and CXL models do not have good handling. The taller CXS model is reasonably nimble in corners thanks to its Magnetic Ride Control suspension. The CX and V6 CXL models feel wobbly inside, so upgrading to the variable Magnasteer configuration available on the CXL V8 and CXS is a good idea if you can afford it. Brakes are the weakest aspect of the Lucerne's driving dynamics. In daily driving, pedal feel is fine, but in emergency situations the stopping distance is the longest of any full-size sedan in this price range. The base V6 engine accelerates adequately, but has less power for this class. The V8 responds smoothly and allows the Lucerne to accelerate to 100 km/h in 7.7 seconds. That's a respectable time, although rivals with a V6 engine, like the Avalon and Azera, are even faster.

The Lucerne's interior is cleanly designed, and the layout of the controls is simple and uncluttered. The leather upholstery is soft, and the designers have done a good job matching the grain patterns of the vinyl and plastics on the dash and doors. Unfortunately, there are still a few low-quality materials in the mix, and build quality is inconsistent. The front seats are typically for two people, but a 40/20/40 split bench can be ordered for the CX and CXL, in which case the Lucerne seats six. Cushions and legroom are plentiful, whether you sit in the front or rear. You can fit 17 cubic meters of cargo in the trunk. In addition to the folding rear seats, there is a ski pass-through.