A 2008 Cadillac STS uses an eight-cylinder engine (V8).
In the 2008 STS lineup, Cadillac offered V8 propulsion across the board. The regular STS models were equipped with a 4.6-liter Northstar V8, while the high-performance STS-V variant used a 4.4-liter supercharged V8. There was no factory six-cylinder option for the 2008 STS.
Engine options for the 2008 STS
The two primary engine configurations associated with the 2008 STS are listed below.
- 4.6-liter Northstar V8 — standard engine for the regular STS models (eight cylinders).
- 4.4-liter supercharged V8 — used in the high-performance STS-V variant (also eight cylinders).
In short, both configurations are eight-cylinder designs; the six-cylinder option does not apply to the 2008 STS lineup.
What to know when buying a used 2008 STS
If you are shopping for a used 2008 STS, confirm the exact variant and its maintenance history. The base STS with the Northstar V8 differs from the STS-V in performance and service needs. Here are factors to check:
- Verify the engine type listed in the VIN and owner’s manual (8-cylinder Northstar V8 or 4.4L supercharged V8 in STS-V).
- Be aware of potential Northstar-related concerns such as head gasket issues or oil leaks, which have appeared on some models.
- Inspect the transmission and electrical charging systems, especially on higher-mileage examples.
Consult a qualified technician or Cadillac specialist if you are unsure about the variant or the car’s service history.
Summary
The 2008 Cadillac STS is an eight-cylinder vehicle. The standard model employs a 4.6-liter Northstar V8, while the high-performance STS-V uses a 4.4-liter supercharged V8. There is no six-cylinder option for this model year, though buyers should verify the exact engine variant when evaluating a used car.