Synthetic/dino oil and change intervals...

[BioStroker]

I've been running Valvoline Premium Blue Extreme 5w40 for about 4,000 miles now, and am have a couple of questions I'm hoping to get some opinions on.

1. What kind of change intervals should I go with a synthetic? The guy at Carquest told me I could go 10,000 miles if I just change the filter at 5,000 miles and top off the oil. That sounds high to me, I'm used to every 3,000 miles on dino in a gasser.

2. Is there any reason not to change from synthetic back to dino? The synthetic is expensive, but if I can SAFELY go longer with the change intervals I can see it being worth it. I don't have a bypass oil filter. If not, I'm probably going to switch back to dino. Does it hurt your engine to alternate between synthetic and dino?

3. What's the best dino oil and how long is everybody going between oil changes on dino?

Thanks! If there's anything else I might have missed please feel free to comment.

[breuer69]

Everyone seems to have an opinion when these oil discussions turn up, so I guess I'm no different there, but here are the things I would consider:

If you are going to do extended oil changes do an oil analysis at the regular oil change interval (especially for the 6.0L guys reading this). The high pressure systems tend to shear the oil down in viscosity (more so on the 6.0L).

If you don't have anything beyond stock filtration, you might not be keeping it clean enough anyway.

You won't hurt anything to switch back to dino at your next oil change.

[The_rook]

Get a good filter napa gold , motorcraft , wix. Rotella and change it every 5k.

[dereku]

the 6.0 manual recommends 7,500 miles on regular oil.

[Motown Fire]

What he said............

[SyN]

Stroker: What is or are your driving habits? Do you tow alot?
As Breuer stated above--> The 6.0L are shear monsters on oil. So the oil needs to be changed or have a UOA more often. The 7.3L is easier on oil then the 6.0L, but not by much.

All the dino 15W40 oils will work great if you keep you OCI around 5K miles.
All the Synthetic 15W-40 & 5w-40 oils will work great, just keep your OCI between 7.5K and 10K miles.-->{Maybe changing the filter at 4K miles and adding to fill}.You can use an Amsoil EaO filter, and not have to change the filter at all.

Remember every Powerstroke is different and will act and react differently to certain brands of oil due to the base stocks and additive packages within the oil.

Our Powerstrokes run best on New Clean Oil. If you chose to install a by-pass filtration system. U can extend your OCI with the use of UOA. I've read and experianced many who go 15K to 20K miles between OCI with a by-pass system installed. It's your time and money and your investment. This is just my personal Opinion.

The oil you are currently running is a great oil. Just spin on a top grade of filter and you are good to go. -->Up to 7.5K miles or 10K. Rook has good advice for dino oil.