I had oil changed at a Toyota dealership last week and they put in 0W20, Will this harm my engine? As a note, the manual for our 2012 Tahoe recommends 5W30 synthetic BLEND, which we will continue to use. I am thinking of changing oil today, even though it was just changed last week due to concerns about the 0W20. Thoughts?

 

0W20 can replace 5W20; It depends on your environment, temperature, how you drive....
5W30 that they recommend is for non-synthetic oil;
by the time you get an oil change, 5W30 non-synthetic is probably worn down to 5W20, anyways.
0W20 synthetic is basically the same as non-synthetic 5W30.
My brother is a mechanic, & said he would leave it.