Oil Useage?

[Murray the Cop]

I used about a quart in 4000 miles, mostly hard hywy miles 70-80mph and higher Eastern LI to Queens and back daily, if you call that hywy and a little towing (500 miles-tops).Is this an acceptable amount? The truck has 36000 on it and I started running a bypass system at about 24000. I didn't notice the usage with the shorter oil change intervals(3000) before the bypass was installed. I had the oil analysis done after 7000 with the system (used a little over a quart at 4000), all was fine but I changed it anyway. I intended on another analysis after another 7000 and if all was still well waiting untill 10000 to change it. I am running synthetic oil in the truck and was under the impression it wouldn't burn. No leaks either so its going somewhere. The truck runs good and I have not had any real problems. Any info is appreciated. Thanks

[DmaxMaverick]

Some oil usage is normal. One qt. at 4000 miles is not excessive. As long as there are no issues causing oil usage, how much depends on the brand and type of oil, more than anything. Some brands are more volitile than others, and synthetic oils tend to vapor off less.

If you are concerned, once you have a base line of oil consumption, change brands and compare. The consumption is not a bad thing, and will happen with any oil.

I claim zero oil consumption between 7500 miles changes. To me, less than a qt. at those miles is zero. It's normal. If my changes yielded the same coming out as I put in, I'd be concerned. There would have to be something other than oil, in my oil. If I were using dino oil, I'd expect more loss, and be content with that.

[Runaway]

I use a quart between oil changes (10K) w/ Synthetic 5w40 Rotella T. Every diesel I have owned has used oil with Shell products.

Both my Cummins used oil between oil changes with Shell and when I switched to the Chevron (Delo???) they both used very little.

I had an old 6.2L back in early "90's" that used over a quart between the 2500 mile recommended oil changes. I switched to a Citgo diesel oil and had very little consumption between oil changes.