I run Motul 10-60W in my 993 and it uses way less oil.....was burning off a quart between yearly oil changes with Mobil 1 15-50W....last 2 years since the switch... don't have to top it up at all between changes......I have had my car 24 years......

 

jae lee (#handbuiltbyjaelee) built my 3.8 and singer's engines, uses the gibbs DT50 in his builds.