Quote:

I am using Rottella T in my 440 Motor with about 1500 miles on it since rebuild. I heard that Rottella T is best for flat tappet motors. But I recently heard that it causes sludge build up. When I had the valve covers off every thing looked fine. I only drive about 700 miles a year. And change the oil once a year. Should I change to another oil or use the regular 10-40 modern oils with a separate zinc additive?



Rotella is NOT known for sludge build up. Weight wise the most likely oils to sludge are 10w-40 due to their high viscosity improver content. Synthetics not included (they don't need high amount to reach that weight designation)