What kind of oil should I use?

Question

i got a 2004 Pontiac Gran Prix GTP supercharged. Its got 54000 miles. some people tell me to use sythetic others tell me to use conventional oil and yet others tell me to use a special oil for turbocharged cars. who do i listen to?

Answer 1

Synthetic is better, you can go longer between changes and depending on which brand you use it can increase horsepower. Royal Purple is my brand by the way. :)

Some will tell you not to switch from regular dino juice to synthetic because it will make your motor leak or burn oil but my car has a lot of miles and I switched with zero problems.

Answer 2

I know I can give you a better answer here.

I was a manager at a Penz Oil oil change shop for a number of years. I have to tell you that not one reg oil can do when even the cheapest synthetic can.

Your engine has a supercharger on it, it makes more heat for the engine then a non supercharger engine in the same class so any help keeping it cooler and making the engine more slippery is the key for a long life.

With synthetic oil parts that are moving will move more freely then reg oil, less friction is less heat and less gas it needs to move parts.

Your car will gain power and MPG, have less heat and last a lot longer with synthetic.

Your engine is not some factory limited super beast or an aftermarket bolt on so it just requires the recommended viscosity.

In the summer I would run a synthetic 10w30, in the winter and for racing I would use a 5w30.

A urban legend has been you cant changed to synthetic once you put in reg oil, this is just not true, they would then have to explain the synthetic and conventional blends they sell now.

You can also switch back to reg oil from synthetic as well.

When you see the "W" in say 10W40 it means the weight of viscosity of the oil is going to be. In the oil days it used to mean Winter. The first number in 10W40 is what the oil is at a normal temp before the engine starts, so if it was dead winter you would want a lower firt number fo easy start ups, as well the second number 40 is how the oil will get "thicker" as it gets hotter.

So in the summer on your engine you would want 10 because its all ready hot then when it gets hotter it gos to 30.

So why do they have 10w40 you ask, well not every engine is the same, so engines need that bigger 2nd number because they have more clearances between say the crank and the bearing and require a thicker oil as a better pillow. Diesel engines and race engines will use one weight oil like W30 or W40 or even 30W50 and even W60.

You engine is a normal GM engine with slice of HP with the supercharger (nice car I might add) and will not need the super thick oils.

In my GTO I run W30 in the summer (don't drive in the winter tho) when I go race I will put in 5W30 just for the track, as this is a thinner oil that will give me less friction for a better 1/4 time.

I used reg oil to break in my engine then I switched to synthetic oil.

The truth about changing you oil is that with reg oil you need to changed it every 3,000 or 3 months even if you don't put 3,000 on you car, as the oil will break down and loose its protective ability. With synthetic you can get away with 4,000 or 4 months some oils claim higher however I'm not betting my engine on a sales pitch.

If you take anything away from this it's that synthetic oils are just better, they are your little extra insurance on your engine and if and when you sell the car note that you have been using synthetic as if they are in the "know" they will see it's been well taken care of.

It's worth the extra money.

P.S. If you have an older car like pre 95 DO NOT use a conventional oil that's a detergent type (pens oil is) it will eat the gaskets out of your engine.

Good Luck

Answer 3

2004 Pontiac Grand Prix Oil Type

Answer 4

Supercharged and turbocharged cars use synthetic oils. Also luxury and high end sports cars use synthetic oil.
It won't hurt the car if you use a different type of oil, but synthetic offers more protection for the engine.

Answer 5

Well if you havent used synthetic since it was new than no use switching. No real special oil for the supercharged just use top quailty like castrol or pennzoil ,no cheapo oil cause it will leave deposits in the long run and you will start losing hp.. I have a 06 grand prix and i use a castrol 10-30 synthetic blend

Answer 6

just use Castrol High mileage 10 / 40 wt and all will be right with the worl as long as you change it every three months. If you space out and drive 6 months use Castrol Synethic Motor oil. My GTP went 138,000 on the original engine.

Answer 7

With today's tech and an engines reliance on the computer. It does not make sense to use anything other than what the manufacturer recommends. If you make a change and your engine runs cooler than it should, the computer will compensate and give it a richer fuel mixture. End result, it will be harder on gas than it should be. However minute, in the long run it will come from your pocket.

Answer 8

usually tells you on oil cap ive seen it on all cars i worked on but use high quality oil penzoil quaker state,castrol ect.

Answer 9

check out Amsoil 5W-30 synthetic: http://www.amsoil.com/redirect.cgi?zo=1463115&page=StoreFront/asl


browse Amsoil products: http://www.amsoil.com/redirect.cgi?zo=1463115&page=products