I have an '05 and I'm thinking about switching to synthetic so I don't have to change the oil every 3,500 miles. I remember reading some threads I found and people said that 12,000-15,000 miles was the best time to switch. Would switching around 25,000 miles be detrimental at all?

 

i wouldn't do that

 

Why wouldn't you do that?

I cant think of any reason why you wouldn't want to switch it at 25K. It might not be ideal, but lets be honest how much engine wear actually takes place between 15K and 25K, my guess is it is but a fraction of what takes place during the break in period.

I say go for it.

 

I think I probably would but I also believe their is no single right or wrong answer.
If you drive your car daily there may be little to no advantage.
But on the other hand......who knows?
If you would feel better about using a synthetic, then use it.
Not only are we treating our car to what we believe may be a super lube, we are also treating ourselves to some peace of mind that we really are doing the very best we know how to take care of it.

 

I misread what he wrote. I was under the impression that he wanted to switch to synthetic and switch his oi change interval period to 25k miles

to the OP, go for it. You will notice a difference in running smoothness right when you start it up.

 

I daily drive it and since I'm at school its tough for me to go home every 3000 miles to change the oil. I'm thinking if I switch to synthetic I could at least extend the interval to 6k-7k.

 

I wouldn't recommend extending the interval to much, just because it is synthetic doesn't mean that it wont get just as dirty as conventional oil.

 

That's what the oil filter is for. The recommended change interval is 7500 for normal conditions, 3750 for Severe conditions. Personally, I run 5000 mile intervals with synthetic and consider it overkill.

 

^^ I agree, i know people that change their oil every 3,500...on synthetic. Why would you not just run conventional? Isn't extending the life of your oil the main selling point of a synthetic?

 

As long as you change your oil filter at normal intervals, you can usually run synthetic oils for 10-15k. It all depends on the car. Just because JoeX's car can run it 15k, doesnt mean JoeY's car can without problems.