2004-2006 PONTIAC GTO
AUSTRALIA’S MUSCLE CAR SCENE PARALLELED America’s but managed to last longer than the U.S. version. While American cars were choked with air pumps and catalytic converters and suffered the ignominy of the 5-mph bumper, the Aussies had Ford Falcon GTHOs, Chrysler Valiant Chargers, and Holden Monaro GTSes (and even smaller Holden Toranas when properly equipped) well into the 1970s.
ENGINE
The GTO quickly got a reputation for cheap speed in the used car market, so gearheads sought them out—and frequently beat on them. Whether it’s the 350-hp 5.7-liter LS1 from 2004 or the 400-hp 6.0-liter LS2 from 2005-’06, watch for aftermarket parts, or signs that engine hardware has recently been removed and/or replaced. The GTO’s front-sump oil pan can starve the engine of oil in extreme circumstances, and that can result in damaged bearings and audible knocking. The 2004 (and some early ’05) models have a plastic engine cover that often rubs against the fuel line on the driver’s side, potentially causing a leak.
TRANSMISSION
More than 60 percent of all 2004-’06 GTOs were equipped with the Tremec T56 six-speed, a $695 option when new, making the standard 4L60E automatic the rarer choice. (Automatic-equipped cars are said to be marginally quicker at full acceleration down the quarter-mile.) Both options are robustly engineered and are easily enough repaired but watch for signs of abuse. Stick cars should have the clutch fluid changed regularly; black fluid in the reservoir is a sign of skipped maintenance.
INTERIOR
The GTO’s raved-about-when-new quality interior didn’t always hold up. Headliners tend to sag. Seams in the leather seats are prone to splitting, but none more than the rear-seat headrests, which can bake in the sun if the rear window isn’t tinted. Heavy keychains can
