Oil Changes

[H2er]

I recently took my H2 in for routine service they once again overfilled my oil by 1/4 of a quart. I do not really know if this will hurt or should i remove some from the drain. the thrash marks look #### #### #### #### my oil proceeds almost up to where the number start which is about 1/4, any suggestions. The tech took the oil and messured it before he put it into the truck. it has happened once before i am really getting tired of having to take out oil. ?

[Dug]

H2er - 1/4 of a quart will not hurt the engine. The 6.0 liter takes a even 6 quarts. So it should be hard for the mechanic to overfill by a 1/4 . I would guess that the tech isnt letting all the oil drain down into the pan after you have shut the engine off. Is this a quickie oil change place? DO not overfill more than a 1/4 of a quart. good luck

[Dug]

Another idea - The tech is filling a two gallon container out of a large oil tank up to where he thinks 6 quarts is , and not actually using 1qt containers .

[Arizona Hummerboy]

I would take it back and have them to take out some of the oil. This happened a few times to my wife car, and we take it back to them and they will remove some of the oil out.

[mdoyle]

I think a lot of the quick oil change places overfill to offset installing a dry filter and to prevent rework from people complaining their oil wasn't filled all the way up.

1/4 quart would barely show on the stick, my guess is if you're noticing it, then it's more than 1/4 quart.

For this very reason, I change the oil in our vehicles myself and recycle it at O'Reilly Automotive (parts store) for free. It's also a good opportunity to check everything over, grease the zerks, and prevent surprises that sometimes happen when you never crack the hood and spend time under chassis.

[H2er]

The Reply:

I have taken this this truck to 2 different GM dealers each time they overfilled by some amount i assume its a 1.4 of quart because its about the same distance as one of the 4 hash markes. The dealer says don't worry about it. I have to take the truck to there place or it will void my warranty.

i know this sounds stupid but my oil pressure has increased slighlty, maybe i should consider letting a little oil out.

[mdoyle]

Oil pressure is independent of oil level to the point that the sump runs dry so as long as the pick-up is submerged then pressure should follow a parabolic curve matching rpm to the point of bypass or relief.

The risk of an oil level above the design point is excess counterweight incursion, rod and piston skirt contact that can cause foaming resulting in loss of pressure, and excess oil consumption. Extreme overfilling can result in damage to the PVC system and seal failure.

[H2bill]

Originally Posted by H2er

The dealer says don't worry about it. I have to take the truck to there place or it will void my warranty.

How's that work? There's no way they can void your warranty for having your oil changed (and documented) by someone else (or yourself).

[CO Hummer]

Originally Posted by mdoyle

Oil pressure is independent of oil level to the point that the sump runs dry so as long as the pick-up is submerged then pressure should follow a parabolic curve matching rpm to the point of bypass or relief.

The risk of an oil level above the design point is excess counterweight incursion, rod and piston skirt contact that can cause foaming resulting in loss of pressure, and excess oil consumption. Extreme overfilling can result in damage to the PVC system and seal failure.

Dang....... I was gonna say '220, 221, whatever it takes'.

[H2er]

Good Info Thanks, Should i check the oil after it has been warm and then let sit for say 10 minutes to get a true reading. The owners manuel say check it warm but i rather hear from one of you guys here in the fourm.

[CO Hummer]

Originally Posted by H2er

The owners manuel say check it warm but i rather hear from one of you guys here in the fourm.

The other thing you should do is put a tiny bit on your tongue. If it tastes soapy, you're probably ok. If it has a metallic/oily taste, then get it drained because you likely have a pressure issue.

[mdoyle]

I like to check the oil when I'm buying gas since it's level and the engine is warm. There will be some oil retention in the upper galleries, under the valve covers, ect so warm measurement is the best indicator.

With that said, you really shouldn't have a situation where the oil is retained anywhere in the return areas unless there is excess sludge build-up. The lifter valley, upper cylinder head areas, and internal block low pressure pathways all retain some oil as it drains downward towards the pan, but hot and cold readings should still be within safe levels is you're using the right viscosity for the local climate.