Ive been debating, and i want to switch to durablend, i have 111kmiles, ive hear horror stories about oil leaks and stuff w/ full synthetic, therefor i just bought this car, and im a fan of valvoline, the car was ran on castrol dino 10w 30 befor i owned her. Do you think its ok to switch to durablend?

 

synthetic oil only causes leaks because it cleans out all the crap reg oil leaves behind.
It is very clean oil, back home we use to change it every 5000 miles because at 3000 it wasn't even all the way black. It would still have some clear ness to it. At 2000 it would still look like new oil all most.
We use to have a 91 cavalear with over 200,000 miles, we used full synthetic all ways and one day I pulled the valve cover and it was perfectly clean, just bare metal under a film of oil. That is why I all ways use it now.
It is going in my 3.4 after I break it in.
Oil is oil as long as you have as much as you need in the crank case, it all does the same thing.
I think I'm going to run it in my little toyota for a season over here because there is a lot of black shat up in the valve cover and synthetic should clean it out. I don't think any one has ever put synthetic in it. It might clog the oil filter.

 

Oil Pan pretty much covered everything. I got my car at 70k, and i switched everything over to full synthetic.. i even use synthetic grease where applied. I once saw the poster child for all synthetic oils, when i took the oil pan off of an 84 honda with well over 150k on it. Not one drop of sludge, just regular ol' oil in there. I was pretty impressed, actually. That being said, and just to reiterate what Oil Pan said, as long as you change it every 3k, you're fine using about anything.

 

Just change it before it starts breaking down.
3000 for reg oil
5000 for synthetic