I have a 2000 s type 4.0, i'm planning on changing the oil this afternoon. what is the best weight to use?

thank you in advance

 

You will find that 5W-30 will be the recommended weight oil to use. A TSB was issued lowering the weight oil that is recommended from 10W-30 to 5W-30 with the intent of increasing mileage. As for conventional over synthetic, there are many different thoughts out there and I will leave that up to you. There are pros and cons for both sides.

So, you can use either 10W-30 or 5W-30. IF you live in a hotter climate, the 10W-30 may be a bit better. The slightly thicker oil will help coat the metal surfaces and provide better wear protection. But, if you see this oil staying in the car until the temps drop into the 40's and what not, going with the 5W-30 may be a better choice.