Switching From Conventional To Synthetic Oil?

[Hybrid Fever]

I've been running Castrol GTX 5W-30 conventional oil for about 10,000 miles now since my engine rebuild, and I want to switch to Mobil 1 5W-30. My question is, Do I have to have my engine flushed out, or do I just put the synthetic oil in next time I change my oil?

[sassage]

just switch

[fizzbob7]

people sometimes have problems going from synthetic back to mineral oil, but your situation really doesn't give people problems.....drain it pretty good and replace the filter then put in the synthetic oil.......

[SpeedFreak_77_]

just switch..change filter

[Transparent]

like fizzbob said, Ive only heard of issues going from synthetic to conventional

[mls]

Some people like to mix mineral with synthetic. So, having a little mineral oil residue in the engine should not cause any problems. Just follow the previous replies.