I have an '02 Vic in central Florida. Currently, I change the engine oil and filter (always with Motorcraft) every 5,000 miles. Currently there are 46,000 miles on the clock.

For the last change I used 10W-30 instead of the recommended 5W-20 oil. Does anyone know whether this is likely to have any long term ill-effect on the engine.

Thanks.

 

I don't think it will hurt anything. We buy our oil in bulk, and use 10w40. We have had Crown Vics since 1984 and have not had any oil related engine failures. I am not saying that is what to do, I am just stating we have had real good luck using it in the CVPI.

 

The 5W-20 was really designed to reduce the amount of hydrocarbons produced and put into the air. Also to help the auto industry meet their CAFE requirements by increasing fuel mileage. A ligher weight oil can disapate heat faster than a heavier weight. However, depending on the quality of the oil used, the lighter oil can loose it's ability to maintain film strength when running at operating temperature and will also have a higher evaporation rate. The heavier oil as stated by way2old will work just fine if a heavier weight oil gives you a peace of mind. Just remember to use a quality oil.