I've been running Rotella 5w40 for YEARS now in my 7.3

I'm not driving it much anymore......about 100 miles a month...

Trying to keep the miles down.....

I've got just 145k on my L99....

I want to justify changing oil more often.....

Is it ok to switch BACK to DINO 15w40 Rotella at this point?

 

Yes. Either way is fine. If your not driving it much, you may want to have a sample tested annually for about $25.00 That way your not changing Oil more often than necessary.

 

Thanks! I like the Shell Rotella Oil in general!

 

I am thoroughly convinced that synthetic oil is far superior to conventional. I have ran synthetic in several vehicles with great results. It lubricates better. It stays cooler. And, it doesn’t break down as quick.

I am now considering changing my 2001 7.3 over to synthetic. My only concern is that it may cause oil leaks to pop up. As you guys know, 7.3s are prone to oil leaks and I’ve had several. Synthetic cleans much better than conventional therefore the leak concern.

Anyone here have experience with this?

 

In my personal experience, no. I’m sure it happened to one guy one time somewhere and before you know it an Internet forum legend was born. Conventional and synthetic oils are fine to use together in a pinch or if you want to switch from one to the other on an OCI. If your really want to clean that motor out run an OCI with Redline 15W40 Diesel. The base stocks they use in that are quite a bit different than what you typically find in automotive engine oil (more common in jet/turbine lubrications) and that stuff really cleans.