I put an oil catch can on our 2019 Prime and I catch about 3 ounces between 10k mile oil changes and at 33% HV over that period. I won't have data on our Prime for the egr cleaning until 120k miles when I do the spark plugs. But the gen4 with the battery up front has crammed everything together, making the egr access more difficult. But I'll get the data and share some pics when the time comes 4 years from now.