About to put a hughes kit on my 5.9 intake and wondered what other people have done about oil after. I'm at 204678 miles. Should I switch to syn or keep it regular? Clean out the sludge or is that holding my motor together? Stick with 10w30? Been putting in castrol high mileage 10w30. Let's hear some personal experiences.

 

I was going to start on mine today but going to delay it for a week due to weather. Once done I will continue with the same oil I been using -regular 10/30. I am at 148k miles. After about 170k I plan on using the high mileage regular 10/30. My decisions are based on a tight budget. If I had a bigger budget and there was a benefit to using synthetic, on any of our rides, we would.