Recently, we took a closer look at the availability of the Aisin AR5 5-speed manual transmission, which was utilized by a somewhat-eclectic array of GM vehicles, including the Hummer H3, Chevy Colorado and GMC Canyon pickups, as well as the Pontiac Solstice, Saturn Sky and Opel-Vauxhall GT. Today, we’re back to take a look at the massive amount of parts used by GM Kappa vehicles.
As a quick refresher, the GM Kappa platform is a vehicle architecture engineered by General Motors for sporty, subcompact rear-wheel drive applications. The now discontinued platform underpinned the Pontiac Solstice, Saturn Sky, Opel-Vauxhall GT, Daewoo G2X, as well as the Tauro V8 Spider offshoot.
“We knew from the start that we would do it right or not do it at all; the support for that decision came from the very top,” said GM Vehicle Line Executive, Lori Queen, back when Pontiac Solstice transition from concept to a real product. “It has been an experience whereby the size and strength of GM was mobilized on a global scale to get the job done immediately.”
Kappa Platform Parts Interchangeability
Amongst Kappa vehicles themselves, every mechanical component from the lug nuts to the engine air filter should be identical, meaning one should be able to take a strut assembly from a U.S. market Solstice and bolt it to a Euro-spec Opel GT or even the Korean-spec Daewoo G2X. However, it’s worth noting that spring rates vary between model variants, and automakers may have tweaked the suspension settings for a particular model.
Other variations include single-outlet exhausts for base models versus dual-outlet exhausts for performance models, as well as limited slip differentials and wheel availability. All Kappa vehicles feature an independent, SLA-type suspensions in the front and rear, along with coil-over springs wrapped around monotube shock absorbers. The short-long arm suspension designs feature forged aluminum upper and lower control arms that are both strong and lightweight. The rear suspension feature a toe control link and the rear differential housing has an optimized three-point mounting design.
Below is a list of components that should be interchangeable across all GM-built Kappa models:
- Chassis & Suspension
- Wheels and wheel hub assemblies
- Strut assemblies
- Top hat
- Sway bar, end-links and bushings
- Steering rack and tie rods
- Braking system
- Calipers and pads
- Brake lines
- ABS modules
- Powertrain / Drivetrain
- All engine and transmission hardware, such as:
- Radiator and coolant hoses
- Fuel injectors and rails/lines
- Coils and spark plugs
- Wiring, sensors, and modules
- Clutch and pressure plate
- Driveshaft and rear differential
- ECM calibration may vary
- All engine and transmission hardware, such as:
- Exhaust system
- Manifold to tip for turbocharged models
- Manifold to tip for naturally aspirated models
And thanks to the global scale approach described above, the GM parts used by the Kappa platform are nearly identical across all vehicle applications, save for the exterior design of Pontiac Solstice.
In the table below, we’ve compiled a complete list of production Kappa vehicles, including the Saturn Sky, Opel GT, and Daewoo G2X.
|Year||Vehicle||Transmission||Engine||Power (hp / kW @ RPM)||Torque (lb-ft / Nm @ RPM)|
|2006-2009||Daewoo G2X||5-Speed Manual (AR5) or 5-Speed Auto (5L40-E)||2.4L L85 Ecotec I4||173 / 129 @5800||164 / 222 @ 4500|
|2006-2009||Daewoo G2X Turbo||5-Speed Manual (AR5) or 5-Speed Auto (5L40-E)||2.0L LNF I4 Ecotec||260 / 194 @ 5300||260 / 353 @ 2000|
|2006-2009||Opel GT||5-Speed Manual (AR5) or 5-Speed Auto (5L40-E)||2.0L LNF I4 Ecotec||260 / 194 @ 5300||260 / 353 @ 2000|
|2006-2009||Pontiac Solstice||5-Speed Manual (AR5) or 5-Speed Auto (5L40-E)||2.4L L85 Ecotec I4||173 / 129 @5800||164 / 222 @ 4500|
|2006-2009||Pontiac Solstice GXP||5-Speed Manual (AR5) or 5-Speed Auto (5L40-E)||2.0L LNF I4 Ecotec||260 / 194 @ 5300||260 / 353 @ 2000|
|2006-2009||Saturn Sky||5-Speed Manual (AR5) or 5-Speed Auto (5L40-E)||2.4L L85 Ecotec I4||177 / 132 @ 5800||173 / 235 @ 4800|
|2006-2009||Saturn Sky Red Line||5-Speed Manual (AR5) or 5-Speed Auto (5L40-E)||2.0L LNF I4 Ecotec||260 / 194 @ 5300||260 / 353 @ 2000|
|2012 – N/A||Tauro V8 Spider||6-Speed Manual (T56) or 6-Speed Auto (6L80-E)||6.2L LS3 V8||440 / 324 @ 5900||432 / 586 @ 4600|
Two inline Ecotec four-cylinder engines were available for GM Kappa models, including the 2.4-liter L85 which was utilized by entry-level models, and the 2.0-liter LNF, which was for the upper echelon variants such as the Pontiac Solstice GXP and Saturn Solstice Sky Red Line. There is a slight difference in the L85’s power output, however, as it makes slightly more horsepower and torque in the Sky than in the Solstice.
Notably, the LNF can be found under the hood of 2008-2010 Chevrolet Cobalt SS coupes and sedans as well as Chevrolet HHR SS sporty “panel vans”. However, a distinct difference is that the engine application for Kappa platform vehicles is longitudinal with a rear-wheel-drivetrain versus the transverse setup for the front-wheel-drive Chevy models, which results in more parasitic power loss in the drivetrain (plus the ability to pretend one is a Formula drifter).
GM Parts Bin Sharing
In order to decrease cost by leveraging economies of scale, the Kappa architecture used a whole bunch of major components from nearly every GM division/brand and modern platform at the time, such as:
- Rear axle and differential from the Cadillac CTS
- Sigma platform
- Pontiac Solstice interior storage bin from Cadillac XLR on the
- Y-Body platform
- Passenger-side airbag, steering column, and exterior and interior door handles are from the Chevrolet Cobalt and Pontiac G5
- Steering wheel on the Pontiac Solstice is from the Pontiac G5
- Backup lights for Solstice are from the GMC Envoy
- GMT 360 platform
- Heating, ventilating, and air conditioning modules are from the Hummer H3
- Front fog lamp assembly on the Pontiac Solstice is from the Pontiac Grand Prix
- 5-speed manual transmission is from the Hummer H3, GMC Canyon, and Chevrolet Colorado
- 5-speed automatic transmission is from the Cadillac CTS, STS, and SRX
We are continuing to compile information in an effort to create a comprehensive resource for all things GM. If we’ve missed anything crucial, shoot us a note here.
Including Ecotec engines, Aisin transmissions, suspension components, and more.
General Motors has yet to recall the cars, and the NHTSA has not opened an investigation.