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General Information by Model Year
There have been many changes in the ten model years of the fourth generation V6 F-Body. Here are some of the more noteworthy ones. 1993
1993 marked the introduction of the all-new fourth generation of the F-Body. The engine available was the L32 3.4L V6. For these models, the standard transmission was the Borg-Warner T-5 5-speed manual, with the 4L60 4-speed automatic available as an option. Final drive ratio was 3.23. 1993 models came with 10.7"single-piston caliper front discs (the same as their V8 counterparts) but came with 9.5" rear drum brakes, a steel two piece driveshaft, a 16.9:1 ratio steering rack, 30mm front sway bar, and a 17 mm rear sway bar. Noteworthy V8 Parts 1994
In 1994 the 4L60 automatic transmission was overhauled and re-designated as the 4L60-E. The major difference was that the new transmission was computer controlled. There were no other significant changes for the 1994 model year. Noteworthy V8 Parts 1995
In 1995 there were two engines available. Initially the L32 3.4L was standard, with these being almost identical to 1994 models. Halfway through the year a few F-Bodies in The 95 L36 marked the debut of OBD-II (On Board Diagnostic system, second generation) in the V6 F-Body. The OBD-II system included 4 oxygen sensors: one in each exhaust manifold, one in the Y-pipe before the catalytic converter, and one in the intermediate pipe just after the catalytic converter. Brakes, driveshaft, steering rack, and sway bars were identical to models of earlier years. Noteworthy V8 Parts 1996
In 1996 the L36 became the only available engine. The standard transmission was the Borg-Warner T-5 5-speed manual, with the 4L60-E 4-speed automatic available as an option. The final drive ratio for the manual was 3.23, with 3.08 being standard for cars with the automatic. New 5 spoke alloy wheels were made available. Brakes, driveshaft, steering rack, and sway bars were identical to models of earlier years. 1LE Package same as 1994. 1997
1997 models saw a revised interior that featured a flip-out cup holder. Orange daytime running lights became standard. Camaros were given redesigned tail lights. The Firebird W68 Appearance Package was introduced that included ground effects, fog lamps, and the Y87 package dual exhaust but with aluminum tips. 1998
1998 saw the F-Body's most dramatic redesign since the introduction of the fourth generation in 1993. Both the Firebird and the Camaro were given freshly redesigned front ends. The Firebird's two pop-up headlights were eliminated and quad lights were introduced. The Camaro saw its headlights dramatically redesigned as well. The Firebird was given new graphics and new "honeycomb" taillights. The air intake system for the L36 engine was radically changed to accommodate the new hoods on both the Firebird and the Camaro. The airbox changed to a lid type, with the lower airbox being the same plastic piece as the upper radiator support. It uses a larger panel filter than the previous design. The exhaust hangars were changed, while the pipe routing is the same as in previous years. 1998+ cars no longer have an oxygen sensor just before the catalytic converter. Automatic cars get a one-piece steel driveshaft to replace the two piece steel unit used in earlier years. The suspension was revised with stiffer springs (front spring rates were increased from 39 N/mm to 45 N/mm while rear spring rates increased from 16.9 N/mm to 19.9 N/mm) and "softer" sway bars (28 mm front, 15 mm rear as compared to the 30mm front and 17 mm rear in earlier years). The end result was to make the ride smoother while maintaining handling. Completely new, considerably larger brakes were introduced on 98's, and for the first time four-wheel disc brakes were standard on all F-body models. The front discs were upgraded to use 11.9" rotors and dual piston PBR calipers (from the 10.7" discs and single-piston calipers of earlier years), while the rear discs consisted of 12" single-piston calipers. Additionally, shocks for both V6 and V8 Firebirds were revalved for enhanced ride. Noteworthy V8 Parts 1999
In 1999 the L36 saw its first redesign since its introduction in late1995. A new intake manifold was introduced that was straight, not angled slightly as in earlier years. The cable-controlled throttle was replaced with an electronic "drive by wire" system. The new throttle plate opens and closes by way of an electric motor based on inputs from the TAC module, which reads pedal position and movement with three different sensors. For Y87 automatics, there is a PCM update from GM that will "correct throttle lag during heavy acceleration". For non-Y87 automatics and all manuals there is no correction because GM decided that there is no need for one. All V6 cars get a one-piece steel driveshaft to replace the two piece steel unit used in earlier years. There is a bulletin out warning that excessive speeds (excess of 125 mph) can cause the tail shaft extension seal to vibrate out and allow all of the transmission fluid to leak out. The fix as recommended by GM is to replace the steel one piece driveshaft with the steel two piece version from earlier years; the fix recommended by many automotive enthusiasts is to replace the steel one piece driveshaft with an aluminum one. SGS (Second Gear Start) became standard on all automatic cars as a type of traction-control-like system. It starts the transmission in second gear instead of first to help prevent wheel spin on slippery surfaces. It does hurt the transmission (it heats the fluid more because the torque converter is slipping more) and offers no benefit during everyday driving. The old disc-type limited slip differential ( Noteworthy V8 Parts 2000
The most significant change for year 2000 models was new tubular exhaust manifolds. The throttle opening map was revised to prevent any throttle lag. It is reported that many automatic cars (but not all) received the limited slip differential and 3.42 gears standard, although official GM documents state that these come only with theY87 performance package. Noteworthy V8 Parts 2001
2001 saw a few minor changes from 2000 models. The wheels were dropped from the available components as they were now the "new" WS6 wheels (with different wheel caps). Noteworthy V8 Parts
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