General Motors' largest division gives its midsize TrailBlazer SUV performance enhancements, branding it with the same SS badge found on its Cobalt, Impala, Malibu, and Monte Carlo cars.
   TrailBlazer SS is a truck-type SUV available with rear-wheel drive or all-wheel drive. Instead of the base 291-horsepower 6-cyl engine or the 300-horsepower V8, Chevy drops in a slightly detuned version of the Corvette's V8. The 6.0-liter engine makes 395-horsepower in this application, and it teams with a 4-speed automatic transmission. Chevy claims a 0-60 mph acceleration time of 5.7 seconds.
   In keeping with the performance theme, this TrailBlazer gets a sport-tuned suspension that rides one inch lower than the stock 2WD model. The standard antilock 4-wheel disc brakes are larger than those in standard versions. The brake pad linings are taken straight out of the Corvette and are designed to resist fade, a reduction in stopping power caused by a buildup of heat.
    Like its siblings, the SS comes standard with GM's Stabilitrak traction/antiskid control as well as OnStar assistance. Curtain side airbags are optional, as are DVD entertainment and navigation systems. The SS has specific interior trim, but like other TrailBlazers, materials quality significantly trails key import and domestic rivals. Maximum towing capacity is 6,700 lb with 2WD and 6,500 lb with AWD.
    SS was a $5,100 option package for 2006 LS and LT TrailBlazers. For 2007, the SS is a separate model, with 2WD versions starting at $30,745 and AWD models at $33,045.

    Chevy's full-size pickup trucks offer performance models as well. Silverado 1500HD models are 4-door crew cabs with full-size doors. Silverado SS is an extended cab. All have a 345-horsepower 6.0-liter V8 engine and a 4-speed automatic transmission. Most Silverado V8 models have a 295-horsepower 5.3-liter engine.
    Rear-wheel drive is standard. The 1500HD can be ordered with GM's Autotrac four-wheel drive that can be left engaged on dry pavement and includes low-range gearing. No 4WD or all-wheel-drive system is available on SS. When properly equipped, the 1500HD can tow up to 10,300 lb, the SS 7800.
    Note that GMC sells the similar Sierra 1500HD and luxury-trimmed Sierra Denali, both of which share Silverado's basic design and powertrains.
    Silverado will be redesigned for 2007 based on the underskin design of the Tahoe and Suburban SUVs. The 2006 1500HD starts at $29,645, the SS at $33,280.

    This proof-of-concept pickup truck blends Dodge's Ram 1500 pickup chassis with Viper's high-performance powertrain. Dodge bills Ram SRT10 as the world's fastest pickup, with a mid-5.0-seconds 0-60 mph acceleration time. That puts this big pickup in the realm of the BMW M3 for straight-line acceleration.
    The SRT10 gets it done through the Viper's 500-horsepower 8.3-liter V10 engine (vs. Dodge's 345-hp 5.7-liter Hemi V8). It's rear-wheel drive only and offers a regular cab or a 4-door Quad Cab model. Regular cab models use a 6-speed manual transmission, Quads a 4-speed automatic. Other features that distinguish the SRT10 from other Rams include: 22-inch wheels, sport suspension and seats, and specific trim. Quad Cabs can tow up to 8,150 lb.
    If you want one, be aware of two things. First is SRT10's fuel thirst, which is heavy even for a big pickup. Test SRT10s have averaged 9.2-11.3 mpg on the required premium-grade fuel. These are among the lowest ever recorded in a Consumer Guide(r) evaluation. Also, be aware that 2006 is the last year for these models. The regular cab SRT10 starts at $47,605, the Quad Cab at $51,810.

    Though not quite as outlandish as the Ram SRT10, Chrysler's Jeep division has its own high-performance utility vehicle, the midsize Grand Cherokee SRT8. This SUV seats five and has the same 420-horsepower 6.1-liter V8 engine found in the Dodge Magnum SRT8 and Chrysler 300C SRT8. Other Grand Cherokees with V8 engines have 235 or 330 hp. Jeep says the SRT8 does 0-60 in 5.0-seconds flat, which would make it faster than the BMW X5 4.8is or Porsche Cayenne Turbo.
    The Grand Cherokee has standard AWD, and unlike other Jeeps, it's not meant for serious off-road use. It also has specific sport suspension, Brembo-brand brakes, 20-inch wheels, sport seats, and specific trim. Maximum towing capacity is 3,500 lb.
    Traction/antiskid control is standard on SRT8, but curtain side airbags are optional. No changes are in store for 2007 versions of the SRT8, and the '06 models have a starting price of $39,300.

    Domestic manufacturers aren't the only ones to offer high-performance versions of their SUVs. British luxury-SUV maker Land Rover offers a supercharged model of its Range Rover Sport. Based on a modified LR3 platform, the Sport is a smaller version of the flagship Range Rover SUV and the brand's best-selling model.
    The base $56,535 HSE model uses a 300-horsepower 4.4-liter V8 engine. For an additional $13,000, Land Rover offers the Supercharged model, with a 390-horsepower 4.2-liter supercharged V8. Both models team their engines with a 6-speed automatic transmission.
    That engine propels the Supercharged Sport from 0-60 in 6.7 seconds in Consumer Guide(r) testing. Power comes with a steep price at the pump, however. Test Superchargeds averaged 11.1-11.2 mpg in mostly city driving on the required premium-grade fuel. Don't expect much better on the highway.
    Though several interior components may fall short of the Range Rover Sport's luxury promise, these SUVs have some innovative technological features. Land Rover's Terrain Response System is designed to tailor the standard AWD system for certain off-road driving conditions.
    Superchargeds also include Rover's Dynamic Response Suspension, which is designed to counteract body lean in turns. Maximum towing capacity of the Supercharged is 7,718 lb.

    Mercedes-Benz is getting into the souped-up-SUV business, with performance-tuned AMG versions of its five-passenger ML-Class and six-passenger R-Class.
    Formed 38 years ago, AMG started as an independent tuning company for Mercedes' cars. The company grew to become an arm of Mercedes-Benz. The first AMG car to debut in the United States was the 1995 C36, with a 282-horsepower 6-cyl engine.
    AMG now has a hand in producing high-performance versions of all Mercedes' cars, from the 362-horsepower V8 engine C55 to the 604-horsepower V12 SL65. The 2007 ML63 and R63 aren't the first SUVs to go through AMG's finishing school, however. From 2002-2005, Mercedes offered the G55 AMG, a tuned version of its luxury, but military-styled, "G-wagen."
    ML63 and R63 debuted at the 2006 Chicago Auto Show. Both use a 503-horsepower 6.2-liter V8 engine. The current top-line ML500 and R500 each have 302-horsepower. This engine is the first developed entirely by AMG. It doesn't share any parts with other Mercedes powerplants. A 7-speed automatic transmission gets the power to the pavement.
    Both SUVs have standard AWD and traction/antiskid control, specific sport suspension, and Mercedes' AIRMATIC adjustable air suspension. Also standard is hill-descent control, designed to limit speed while driving down steep grades. Mercedes' Hill Start Assist system is designed to keep the vehicle from sliding backwards while driving up a hill. The ML63 has 20-inch wheels; the R63 has 19s.
    Mercedes estimates a 0-60 mph acceleration of about 5 seconds for both vehicles, and it says each vehicle is capable of an electronically-limited top speed of 155 mph.
    Prices have not yet been announced, but you can expect these SUVs to command a substantial premium over the current top-line ML500 ($48,500) and R500 ($55,500).

    The idea of a Porsche SUV remains a vile one in the minds of many. Like it or not, the Cayenne is here, and it shares some of its basic design with Volkswagen's Touareg.
    Cayenne base and S models use V6 and V8 engines, respectively. The top-line Turbo and Turbo S up the ante, with the former using a 450-horsepower 4.5-liter turbocharged V8. The latter has a 520-horsepower 4.5. Both Turbos use a 6-speed automatic transmission.
    Cayennes have a maximum towing capacity of 7,716 lb. Porsche pegs the Cayenne Turbo at 5.5 seconds 0-60, the Turbo S at 4.8 seconds.
    With starting prices of $90,200 for the Turbo and $111,600 for the Turbo S, these SUVs certainly aren't cheap. But for those well-heeled shoppers, price doesn't matter when they're buying the prestige that accompanies the brand.