I have a 2004 mazda 6 2.3 liter. Ive been getting the oil changed at the dealership ever since i bought the car. It now has 49000 miles on it and someone at the dealership said since ive been using normal or semi-synthetic the whole time , that its too late to put synthetic oil in and that it could damage my car since i havent been using it previously. Is this true?

 

BS. You can use syntheitc without any worries.

 

So long as the oil being used previously isn't a parafin based (wax) oil. Quaker State and Pennzoil are both parafin. Over time, this wax builds up. Synthetic oils can wash this build-up off of the insides of the engine and right into your filter. It clogs the filter and can cause oil starvation in your engine.

I prefer Valvoline or Mobil.

 

Ya i figured so! I dont know what oil was used before its whatever mazda dealerships use so i guess that rises another concern thanks to everyone for there input!

 

3 words.

THEY WANT TO MAKE MONEY (ok, 5 words)

in any case. if u use conventional oil, it reuiqres 3500-7000 mile changes depending on ur driving habits. this means more labor profit for the dealer. duhh.