Too much oil??

[LK23]

I took my Cummins 400 ISL into the local Cummins facility for a oil and filter change. This should take 26 3/4 quarts of oil. The technician read the specs for total capacity and added 28 quarts (not allowing for the oil that remain in the engine). I didn't realize this until I got home and checked my dipstick. Now, I am a little over a quart too much.

I called Cummins and the Rep said he would not worry too much about one quart. If it was two quarts, I should remove some oil.

What do you think? Should I run it with too much oil or should I loosen the drain plug and try to take out a quart?

[Ann n Gene]

I would tend to believe the factory rep. If they charged you on the ticket for 28 qts. they are on record and on the hook for any problems that develop, which I feel very confident they will not. We had trucks for years and a quart in that volume gets lost in the shuffle. Did not add oil until they got a gallon low. just my experience and opinion

[LK23]

To further clarify, I took 27 quarts of Rotella oil to the Cummins facility because they did not handle Rotella. After they had the coach for about a half hour I got a phone call from the tech saying he needed another quart. I bought another quart and it was added by the tech before I departed.

In hindsight, I should have questioned more since I knew to bring 27 quarts for the change. I assumed they knew more than me about oil capacity. Bad assumption.

[AFChap]

Only ill effects may be some blow-by spots on the toad if you tow. My ISC takes 21 qt and service places have sometimes put in closer to 24. I have posted a sign in the engine compartment that max capacity is 21 qt ...and when I take it in for service I tell them the max is 21 qt AND that I will PAY for ONLY 21 qt.

[spike45]

As a field service engineer for a Cummins company, one quart over will not cause any issues. Neither will it accelerate crankcase vent tube slobber any more than normal for this engine.

[LK23]

Thanks for the replies.

By the way, I am not overly critical of the Cummins facility. The guy who normally handles RV oil changes was on vacation and the diagnostic tech was filling in for him. Other than the overfill issue, the service was excellent and I will gladly return.

[J Walker]

What the tech was probably trying to do was to add enough oil so that it reached the top of the "Full" mark on the dipstick. Since dipsticks are often wrong, putting in the specified amount of oil is the right thing to do. After that just mark the dipstick accordingly. Just be sure of the specified volume of oil

[LK23]

No, I don't think the tech checked the dipstick. If he had he would not have added the extra quart. Normally, after an oil change I am about 1/8 inch above the full mark on the dipstick. Now, I am about 1/2 inch above the full mark.

[Skip426]

The Tech probably only waited 5 min. instead of the 1 hour rec. for checking oil in the engine. As stated by a previous poster a quart or part of a quart over is not an issue. As you stated, next time they ask for more oil something should click ! Why ?

[Mr_D]

When I change my oil/filter I set the oil level half way between full and add. If I don't it throws oil over the towed until it gets to that level anyway. One there it pretty much stays there till the next change.