Just bought a 2005 Sierra SLT 4X4 with 127,000+ miles on it. Great truck. I usually run Synthetic oil in my vehicles but usually start them on it while very low miles. Could I run Synthetic in this one at this stage of the game or just run reg oil? Thanks for any help .
Synthetic oil is perfectly safe for use in new or high-mileage engines PROVIDED they are in good mechanical condition. However, in older vehicles with high mileage, it may be advisable to use a product such as this first. This will ensure the engine is clean and free of accumulated contaminants that may affect the service life of the synthetic motor oil. Installation of an high quality Oil Filter at every oil change is recommended.
Thanks for any help .