Originally Posted By: 1LOW1
Hi, I'm a bit of a lurker don't post just browse a bit.I took a brief browse looking for some answers but I'm still a little lost. I have an 03 Silverado 2500 with a 6.0 gas. I am starting to use a little more oil than I should be. Roughly 1-2 quarts in 850 mile road trip. I was hauling about 6000lbs and with 4.10 gears my rpm is about 2300. I get no smoke at start up and do leak a little, I am going to clean up the engine and monitor that better. I have just over 200,000 miles and about 8500hrs run time. My questions are is there a huge difference in 5-30 oils such as Penzoil,Quaker State,Valvoline or Castrol. I get the difference between synthetic and high mileage oils but how about the basics. I'm also considering an additive to maybe condition/help my valve seals. I'm not expecting miracles just a little prolonged life from this engine before I swap in another.One of the local mechanics mentioned a flush with Seafoam in the oil then an STP additive, not sure which one however I will need to confirm which one.
Hi 1LOW1, Our Pennzoil and Quaker State motor oils are similar in technology, but their formulations are not the same. Pennzoil puts an emphasis on engine cleanlines, and preventing sludge and other damaging deposits. Quaker State puts an emphasis on durability and second-to-none wear protection.
With that said – and considering that your Silverado’s engine has approximately 200,000 miles on it - we would recommend our Quaker State Defy Synthetic Blend 5W-30 High Mileage Motor Oil for your 2003 Silverado 2500 (which is formulated to “prevent 98% of all future engine wear”). Besides the extra anti-wear agents, the QS Defy is also formulated with extra seal conditioners (to help reduce oil leakage), as well as a higher viscosity (to help with engine sealing and the possible reduction of blow-by). Hope this helps! - The Pennzoil Team