Hello all, this is 22yr old chinese guy from Leeds, West Yorkshire, north england. The car in question is a 1996 Renault Clio Mark1 1171cc engine 60hp, 4 speed manual, weighs less than 900kg which currently has 141,515 miles. The car is used extensively as a pizza delivery vehicle. 80% of the oil milege is used as city stop&go traffic with no more than 4 miles trip 1 way. So with each delivery the car would have travelled less than 8 miles. Engine will also experience a lot of turn on & offs. This oil milege also includes a Track day @ about 4000 miles. Air filter was changed after the trackday just before the 1st sample. Old filter was filthy. The car is filled with Granville Hypalube Fully synthetic 5W-40 engine oil. Oil is produced by granville oil & chemicals. It is a small UK oil refinery company. We do have Castrol Edge, or Mobil 1 selling here, but for this granville oil, it's half the price of those, that's why i chose to use it. (Castrol 40pounds 4L, Granvile 19pounds 5L) I emailed the company to ask what kind of base oil they use in this oil, they frankly replied that they use Group III. Oil type with viscosity: Granville Hypalube Fully synthetic 5W-40 Miles on the oil: 8,815 miles Vehicle type with year and engine: 1996 Renault Clio, 1171cc E7F Naturally Aspirated Throttle body single injection 140,815mi @ time of 2nd sample Usage: Generally, I baby it in 80% of the time, even on the 200mi trip to the trackday, i don't drive more than 60mph on the motorway. Car can achieve at least 47.04mpg (us) 5L/100km on motorway and at least 31.64mpg (us) on pizza delivery. No Make up oil is added because engine use very very little oil. Oil was changed at 132,000mi (strictly it's 131,9xx) 1st sample at 4,297 mi oil life with NO TBN. 2nd sample at 8,815 mi oil life WITH TBN. car manual call for 6,000 mi OCI. I am trying to push it with fully synthetic oil. I WILL CHANGE THE OIL AS SOON AS I CAN, as result is not favourable.