The Northstar is a typically 4.6L V8 engine built by General Motors from 1993 to 2011, almost exclusively for Cadillac. It did make an occasional appearance in other GM vehicles, often as a performance or special option, but spent most of its production life in various Cadillacs. It is designed with a 90° piston bank and was one of GM's most complex engines at the time.
First Generation Northstar
The original Northstar V8 was given the code L37 and produced from 1993 to 2011, the entire life of the engine's production.
| Internal Code | L37 |
|---|---|
| VIN Code | 9 |
| Engine Type | V8 |
| Displacement | 4.6L |
| Aspiration | NA |
| Horsepower | 290 HP - 300 HP |
| Torque | 285 lb-ft - 295 lb-ft |
| Fuel Type | Gasoline |
| Alignment | Transverse |
| Compression Ratio | 10.0:1 - 10.3:1 |
| Bore | 93 mm (3.66 in) |
| Stroke | 84 mm (3.31 in) |
Steve's Rating: 6/10
Second Generation Northstar
The next Northstar design was given the code LD8 and produced from 1994 to 2007. It was meant to provide more torque than the original.
| Internal Code | LD8 |
|---|---|
| VIN Code | Y |
| Engine Type | V8 |
| Displacement | 4.6L |
| Aspiration | NA |
| Horsepower | 270 HP - 275 HP |
| Torque | 295 lb-ft - 300 lb-ft |
| Fuel Type | Gasoline |
| Alignment | Transverse |
| Compression Ratio | 10.0:1 - 10.3:1 |
| Bore | 93 mm (3.66 in) |
| Stroke | 84 mm (3.31 in) |
Steve's Rating: 7/10
Third Generation Northstar
The code LH2 Northstar was produced from 2004 to 2010. It was redesigned to be used for longitudinal drivetrain layouts.
| Internal Code | LH2 |
|---|---|
| VIN Code | A |
| Engine Type | V8 |
| Displacement | 4.6L |
| Aspiration | NA |
| Horsepower | 320 HP |
| Torque | 310 lb-ft - 315 lb-ft |
| Fuel Type | Gasoline |
| Alignment | Longitudinal |
| Compression Ratio | 10.0:1 - 10.3:1 |
| Bore | 93 mm (3.66 in) |
| Stroke | 84 mm (3.31 in) |
Steve's Rating: 6/10
Fourth Generation Northstar
The code LC3 Northstar was produced from 2006 to 2009. A 4.4L (266.7 cu in/4,371 cc) supercharged Northstar was used in the 2006 Cadillac STS-V and Cadillac XLR-V. The bore was reduced to increase strength and improve head gasket sealing in order to handle the forced induction. Variable valve timing is used on both the intake and exhaust sides of the heads.
| Internal Code | LC3 |
|---|---|
| VIN Code | |
| Engine Type | V8 |
| Displacement | 4.4L |
| Aspiration | Supercharged |
| Horsepower | 443 HP - 469 HP |
| Torque | 414 lb-ft - 439 lb-ft |
| Fuel Type | Gasoline |
| Alignment | Longitudinal |
| Compression Ratio | 9.0:1 |
| Bore | 91 mm (3.58 in) |
| Stroke | 84 mm (3.31 in) |
Steve's Rating: 7/10
Aurora V8
The L47 Aurora V8 was a 4.0L V8 used in one of the last Oldsmobile models, the Aurora, from 1995 to 2003, and the Shelby Series One from 1999 to 2005. Although most of the Northstar's features, including the coolant loss system, remained in this version, the decreased bore increased the engine's weight unacceptably since there was now more material in the block. To reduce that added weight, Oldsmobile used a one-piece glass-filled thermoplastic intake manifold and simplified sequential fuel injection. A new aluminum die-cast structural oil pan baffling system was added to reduce oil starvation during hard driving. A starter interlock prevented the starter from engaging if the unusually-quiet L47 was already running.
| Internal Code | L47 |
|---|---|
| VIN Code | C |
| Engine Type | V8 |
| Displacement | 4.0L |
| Aspiration | NA |
| Horsepower | 250 HP - 320 HP |
| Torque | 260 lb-ft - 290 lb-ft |
| Fuel Type | Gasoline |
| Alignment | Transverse |
| Compression Ratio | 10.3:1 |
| Bore | 87 mm (3.43 in) |
| Stroke | 84 mm (3.31 in) |
Steve's Rating: 7/10
The "Shortstar"
The biggest outlier in the Northstar engine family was known internally as LX5 was produced from 1999 to 2002. It used some of established geometry, like the 90° V layout, but was a V6 instead of a V8. This engine code was one of the first General Motors engine to use coil on plug. Because of the amount of development required to make the engine, GM likely initially planned on building more engines based on the LX5, but after a short three year production run, the format was dropped in favor of their High Feature engine.
| Internal Code | LX5 |
|---|---|
| VIN Code | H |
| Engine Type | V6 |
| Displacement | 3.5L |
| Aspiration | NA |
| Horsepower | 215 HP |
| Torque | 234 lb-ft |
| Fuel Type | Gasoline |
| Alignment | Transverse |
| Compression Ratio | 9.3:1 |
| Bore | 89.5 mm (3.52 in) |
| Stroke | 92 mm (3.62 in) |
Steve's Rating: 6/10
Cadillac Northstar Water Pump Removal
In this video, Falcon's Garage explains how to remove the water pump on a Northstar engine with the rear position water pump layout. This video was published on January 8th, 2016.
- Water Pump Unit
- Water Pump Socket
- Full Strength Dex-Cool Coolant
- 50/50 (Ready to Use) Dex-Cool Coolant
Water Pump Replacement Items
Steve's Thoughts on Northstar Engines
The Northstar engine has a rocky history. It is known among mechanics for its difficulty to repair, and often requires a lot of component removal to access basic parts. It also had an issue early in its life with head bolts that weren't quite enough for the engine. However, when looked after, it makes for a powerful engine that is decently reliable, especially in models after the head bolt fix was put into place.
- Stephen Brand, August 26th, 2023.
- NorthstarPerformance.com
- Cadillac Forums: Small Block V8s
- Book: The Cadillac Northstar V-8: A History (Illustrated)
Related Links
These are links to other sites and haven't been thoroughly looked into (but have been browsed to some degree to make sure there isn't anything blatantly wrong with them) but may be sources of more information.
Overall Rating
Adding together all 5 of Steve's individual ratings, you end up with 33/50.