The 1999 GMC Sierra could be equipped with several different engines, depending on the model and configuration. The most common options were a 4.3-liter V6, a 5.0-liter V8, a 5.7-liter V8, and, on heavier-duty models, a 6.5-liter turbo-diesel V8. Availability varied by whether you were looking at a light-duty 1500 or a heavy-duty 2500/3500 truck.
In 1999, the Sierra lineup spanned light-duty and heavy-duty pickups, and engine choices were tailored to performance needs and towing demand. Gasoline options focused on versatile V6 and V8 configurations, while the diesel was reserved for the heavy-duty models designed for more demanding work. The following breakdown outlines what owners could typically expect in that model year.
Gas engine options
The gasoline-powered engines were available across light-duty Sierra models, with the most common choices being a V6 or V8. The list below highlights the standard gas engines you’d typically find in a 1999 Sierra.
- 4.3L V6 (Vortec 4300) — A V6 option used across many light-duty trucks for balanced power and efficiency.
- 5.0L V8 — A small-block V8 option available on some light-duty configurations.
- 5.7L V8 (Vortec 5700) — A larger V8 option offering increased torque and towing capability for more demanding use.
Gasoline engines provided a spectrum of power suitable for daily driving, mid-range work, and towing lighter loads, with the 5.7L V8 delivering the strongest performance among the gas options.
Diesel option
For those prioritizing torque and heavy-duty hauling, the 1999 Sierra offered a turbodiesel on the heavier configurations.
- 6.5L Turbo Diesel V8 — A turbocharged diesel engine available on the heavy-duty 2500 and 3500 models, valued for high torque at low RPMs.
The diesel option was typically chosen by buyers needing greater pulling power and durability for work or frequent heavy towing tasks.
Summary
In summary, a 1999 GMC Sierra could be powered by a 4.3L V6, a 5.0L V8, or a 5.7L V8 in light-duty configurations, with a 6.5L Turbo Diesel V8 available on heavy-duty 2500/3500 models. Engine availability depended on the truck’s trim level and intended use, making the Sierra versatile for both everyday driving and tougher work tasks.
What problems did the 1999 GMC Sierra 1500 have?
Top 1999 GMC Sierra 1500 Problems
- 4WD Transfer Case Position Sensor/Selector Switch May Fail.
- Heating and AC Temperature and Air Delivery Mode Door Actuators May Fail.
- Fuel Level Sensor Failure.
- Steering May Develop Clunk Noise From Upper Intermediate Steering Shaft.
- Inside Door Handles May Break.
What years to avoid for a GMC Sierra 1500?
The GMC Sierra 1500 years to avoid are 2014, 2015, 2016, and many early 1992 to 2002 models. The best years include 2004, 2009, 2018, 2021, and 2022.
Was the 1999 Sierra a good truck?
As a whole, consumers found the vehicle's comfort and performance to be its strongest features and value to be its weakest. 1219 out of 1659 of owners (73% of them) rank the 1999 Sierra 1500 five out of five stars.
What engine is in a 1999 GMC Sierra?
A number of items set the new Sierra apart from its predecessor. First is a new family of Vortec V8 engines that consists of 4.8-liter, 5.3-liter and 6.0-liter versions. This engine's basic architecture shares its roots with the V8 from the Corvette, and as such it is quick-revving, powerful and gutsy.