Checking your Oil

After the engine has been running and stopped, there can be as much as 3 gallons still remaining in the upper engine. At this point the dipstick will read low therefore it's necessary to wait 10 to 15 minutes. Add oil at or close to the add mark.

 

It doesn't sound bad enough to be concerned about at low idle and bumping it up to 900 is a good idea. The top half of the rod bearing will wear faster than the rest of the bottom. That is the most common cause of oil pressure loss at warm idle. A bottom job will cure it if that's it. Personally I would run it till you dropped down to 20 at warm low idle or you notice it dropping faster than usual. Also have it diagnosed instead of requesting a bottom end done may save you some money. Oil will expand when hot so that is the main reason that as long as it is within the crosshatches you shouldn't need to add any.

 

I honesly don't remember exactly what he said. He doesn't normally offer much information unless he can peddle a product.

 

My 2010 Cummins ISX works like that. If I fill it to the full line on the dipstick it will be at the half mark in two days, if I only fill it to the half mark it will stay there.

 

Crazy. I wonder what the deal is?

 

That may be true if you start a cold engine then shut it off and check the oil. However, my experience does not support that statement with an engine at running temp. In the winter, our trucks run 24/7. With the oil at 190-200 deg, shut the engine off, by the time you open the hood and pull the stick, wipe it then check the level, there is very little oil that has not returned to the pan, perhaps 1/2 gallon. Cold oil would be another kettle of fish. As too when to check it, it should be checked as part of the pretrip, just like the coolant and power steering fluid as JohnP3 suggested.

 

Your dipstick is not calibrated properly then. It is a fairly common problem on truck engines.

 

Next oil change, I check that the marks on the stick are correct. Put in the exact amount that it calls for with filter. Run it and let it sit for 5 min. Then mark the stick at that level for full. I've a few sticks marked wrong, mostly on cat's. Checked 1 C15 a few months back that was using oil if you filled it. Come to find out that the add mark was really at the full level.

As far as checking oil, most manufacturers say to check it at operating temps after the engine has been off for 5 min. In my experience, temp make a very little change in oil level. As long as the engine has been off for 5 min or so, I check it.

 

I was a service manager at a new car dealership. I used to get complaints ocassionally from people because we didn't put the correct amount of oil in their vehicles. The manual would say a certain amount but it did not match up with the dipstick.