I searched to see if this came up before, but can't seem to find anything

I'm using Rotella Synthetic 10/40 with an Amsoil Bypass filter set up.

For normal driving, how long do you think I can go between oil changes? I don't have any long tows planned this year.

I've been changing every 6K and it still looks pretty good when I drain it. I'm thinking I can go further without any harm.

Trying to save some money to buy more Bacon. LOL

 

You would probably have to have an analysis done on the oil when you changed it now to see how much life you have actually used then you can judge it accordingly from there

 

I use rotella 5-40 synthetic "$19bucks a gallon walmart" and a donaldson oil filter "$12 bucks Freightliner trucks" every 8k miles, all tests say Im good to go farther I just dont.

 

Only way to safely extend your drains is to do used oil analysis to get a history of how the oil is performing. I would suggest drawing a sample at 5000 miles and see what the results are. If all looks good, sample again at 10,000 miles, etc. In most cases the company doing the analysis will make comments and/or suggestions.

I have safely extended my drains up to 136,000 miles using oil analysis, Amsoil by-pass filtration, regularly scheduled oil filter changes, and Amsoil HDD 5W-30.

 

I use 5/40 in the winter and 10/40 in the summer.

I had an analysis done last year on a 6000 oil change, and they said the oil was in perfect condition. But they didn't specify what I could extend it too. But most of the last 2 oil changes were running in high heat and/or towing. so I continued with the 6000. I wrapped a couple of refrig magnest on the filters too. The last change, I cut the filters open and didn't find anything to speak of or to worry about. Even the paper was good. The bypass element was due though.

Thanks so far guys. . .let's keep getting opinions. . . . I'm inclined to go to 10 with a 5,000 filter change

 

Why not just run the 5/40 year round? at operating temperature both are 40 wt. oils.

 

The 10 stays in the bearings longer than the 5 does

 

I run 0W40 Mobil1 Synthetic year round with my 08.