I just wanted to ask why I always have to top up my engine oil every month, I get it serviced every year, I even specifically say get it to maximum but 1 month all oil is gone and the engine runs dry but there's no warning light on the dash. The dipstick shows no oil in the sump at all.
I have checked there are no leaks by the sump and the oil filter. What's going on? Thanks for your help!