You mix one qt 530 synthetic oil with four qts regular for change in my 2007 Saturn Ion Is this procedure good engine?

Mixing synthetic and conventional oil is generally acceptable in a pinch, but it's not ideal for long-term use. For a single oil change in your 2007 Saturn Ion, using a 1:4 ratio of synthetic to conventional oil probably won't cause immediate harm. However, it's not the best practice.

Here's why:

* Different Properties: Synthetic oils have different properties than conventional oils. They tend to last longer, withstand higher temperatures, and offer better protection against wear. Mixing them dilutes the benefits of the synthetic oil.

* Potential for Reduced Performance: While unlikely to cause immediate damage, consistently mixing synthetic and conventional oils can slightly reduce the overall performance of the oil compared to using only one type.

* Optimal Protection: For best engine protection, it's recommended to stick to the oil type specified in your owner's manual. If your manual recommends synthetic, using only synthetic will give you the best protection. If it recommends conventional, stick with that.

For future oil changes: It's best to choose either fully synthetic or fully conventional oil and stick with that type consistently. Check your owner's manual to see what type of oil is recommended for your vehicle. Using the recommended oil will maximize your engine's lifespan and performance.