Dodge Viper (third generation, ZB I) buying guide

The convertible came first, as the SRT/10 roadster that dropped the RT/10 name, according to Hagerty. It finally got a folding soft top in place of the old targa-style canvas-and-vinyl one. The 8.3-liter V10 is rated at 500 horsepower, with 525 ft.-lbs. of torque on tap. You can browse every convertible for sale.

The coupe arrived as a 2006 model after its debut at the 2005 Detroit show. Hagerty and HotCars give it a revised cam and heads, for 510 horsepower and 535 lb-ft. Classic Motorsports says the 2006 cars got a 10-horsepower bump. Coupes are listed separately. Dodge skipped 2007 while the factory prepared the 2008 car, so a 2006 is the last of this generation.

Later cars look nearly identical but are a different proposition. The 2008 and later Vipers have a reworked 8.4-liter V10 with 600 horsepower and revised suspension, and they belong to our fourth-generation guide. Classic Motorsports also notes that 2006 was the last year for mechanical throttle body Vipers.

Classic Motorsports says collectors prize special editions such as the Mamba, Copperhead and VOI.9. The Mamba, which arrived in 2004, was a purely cosmetic package, so it adds nothing mechanical. AutoTrader.ca's advice is to buy a well-maintained car as close to stock as possible.

The sources describe a mechanically tough car with annoying body and trim faults, and AutoTrader.ca warns that reliability information is patchy because so few were sold.

Sagging doors

AutoTrader.ca says some owners report door hinges that sag, letting the door ride too low in its opening. That can also let water past the seals.

Window pre-drop failure

The computer that controls the window pre-drop can lose its settings, possibly after the battery goes flat. The glass can then smash onto the roof when the door closes.

Weak window regulators

Regulators on most cars of this era are weak, and AutoTrader.ca says many owners report failures, noise or slow operation. An upgraded regulator became available from 2009.

Rocker panel rust

The rocker panel and exhaust cover areas can rust once the paint is compromised. The panels are expensive to replace.

Airbag module recalls

Recalls cover the air bag control module on 2003 and 2004 cars and the occupant restraint module on 2005 and 2006 cars, which can fire the air bags unintentionally. Check that the work was done.

Clutch switch spring

A recall covers certain 2006 cars built July 1, 2005 to July 31, 2006, for a clutch pedal position switch spring that may break.

Ergonomic complaints

Owners gripe about poor outward visibility, a tight cabin, heavy consumption of premium fuel and the skip-shift function. They are annoyances rather than faults, but you should drive one before you buy.

AutoTrader.ca calls running costs relatively high, citing an aggressive fluid-change schedule, pricey tires, top-end brakes and heavy fuel use. It says some fluids need changing as often as every 20,000 kilometres. It also advises assuming a car needs tires, brakes, a clutch and overdue fluid changes until records show otherwise.

The same source says a pre-purchase inspection typically costs $200 or less, which is small money against the car's other bills. Classic Motorsports adds that the Viper's simple nature makes past abuse easier to fix. For what cars cost to buy, see the price guide.

Buy the best-documented, least-modified car you can find, and treat the records as more important than the badge. AutoTrader.ca calls the powertrain primitive and the car largely reliable, with fussy doors and windows but a solid driveline and electronics if maintained and not abused. Classic Motorsports sees it as a budget supercar. A 2006 coupe has the extra power and the last mechanical throttle, but the sources do not rate it as the better car.

Skip a car with track use, fresh stripe paint, leaks or no fluid history. Insist on a history check, a pre-purchase inspection and proof the air bag recalls were done. Then work every door and window yourself.