Anyone else do oil analysis?

[carguy75]

Continuing the subject of oil changes. Every time I take my car for an oil change at the dealership, they over fill it! I took the car to Jiffy Lube and asked how many quarts they were going to put in. They said 7, I asked them to put in 6.5 and it was perfect. I ask the dealership not to overfill it and they do any way. Anybody else seeing this?

No. I do my own oil changes. However, the service manual does recommend over 8 quarts(8.4 to be exact) for my 5.0 engine, however my dipstick is topped off at 8 quarts. The dealer service techs are probably told to just add what the service manual requires; even if it is about half a quart too much.

 

[Kyser_Soze]

No. I do my own oil changes. However, the service manual does recommend over 8 quarts(8.4 to be exact) for my 5.0 engine, however my dipstick is topped off at 8 quarts. The dealer service techs are probably told to just add what the service manual requires; even if it is about half a quart too much.

The service manual is listing dry fill. When you change your oil, you can never get all the oil out, so you never use the dry fill number for the refill. I don't do my own because after years of owning an oil change business and working in it day after day, I don't want to do it any more. I have an oil extractor that I can use to get the extra out, but it pisses me off because I specifically asked them not to overfill it. They also didn't use synthetic oil like all of my previous oil changes.

 

[carguy75]

The service manual is listing dry fill. When you change your oil, you can never get all the oil out, so you never use the dry fill number for the refill. I don't do my own because after years of owning an oil change business and working in it day after day, I don't want to do it any more. I have an oil extractor that I can use to get the extra out, but it pisses me off because I specifically asked them not to overfill it. They also didn't use synthetic oil like all of my previous oil changes.

The Hyundai service manual just list the amount of oil needed for an oil change as drain and refill for the 5.0 engine; not dry fill. I would assume dry fill would be the total capacity amount listed. However, you are correct that it would be next to impossible to completely drain the oil pan unless you let it drain for a entire day or more. Hence the last remaining half of quart of oil I suppose when I change my oil so that I only need about 8 quarts to top off.

Again I just change my own oil so that I know that it is done correctly.

 

[Seagolfer43]

Continuing the subject of oil changes. Every time I take my car for an oil change at the dealership, they over fill it! I took the car to Jiffy Lube and asked how many quarts they were going to put in. They said 7, I asked them to put in 6.5 and it was perfect. I ask the dealership not to overfill it and they do any way. Anybody else seeing this?

Yes, just had my oil changed at the dealership since it’s still under warranty maintenance. But they overfilled it by at least 5/32. I have read it could be harmful so obviously I have concerns. They did use synthetic so I was happy about that.

 

[EdP]

Yes, just had my oil changed at the dealership since it’s still under warranty maintenance. But they overfilled it by at least 5/32. I have read it could be harmful so obviously I have concerns. They did use synthetic so I was happy about that.

Everything has a tolerance. Anyone know what it is?

Also, the oil put is was about 70F in the shop but was it checked at the same temperature? You'd also have to calculate the volume increase from the engine heat.

 

[Kyser_Soze]

Everything has a tolerance. Anyone know what it is?

Also, the oil put is was about 70F in the shop but was it checked at the same temperature? You'd also have to calculate the volume increase from the engine heat.

I've never seen oil expand with heat, maybe it does, but I have personally changed the oil in thousands of cars and never seen it. The reason to not overfill: "When too much oil is added, the level in the oil pan becomes too high. That allows a fast-moving lobed rod called the crankshaft to come into contact with the oil and essentially aerate it. The result is a foamy, frothy substance that cannot properly lubricate the engine." From jdpower.com

The previous comment about 5/32, that is an odd amount, or rather a very precise amount. 8/32 would be a quarter of a quart or a quarter of the range on your dipstick measurement surface, approximately. The measuring of an overfill is hard to do because there is no measure surface above the full line, so how are you getting such a precise fraction? I've used my thumb to hold the stick above it's insertion point to bring the measurement surface up to where the overfill is, but even that is an approximation.

 

[Seagolfer43]

I've never seen oil expand with heat, maybe it does, but I have personally changed the oil in thousands of cars and never seen it. The reason to not overfill: "When too much oil is added, the level in the oil pan becomes too high. That allows a fast-moving lobed rod called the crankshaft to come into contact with the oil and essentially aerate it. The result is a foamy, frothy substance that cannot properly lubricate the engine." From jdpower.com

The previous comment about 5/32, that is an odd amount, or rather a very precise amount. 8/32 would be a quarter of a quart or a quarter of the range on your dipstick measurement surface, approximately. The measuring of an overfill is hard to do because there is no measure surface above the full line, so how are you getting such a precise fraction? I've used my thumb to hold the stick above it's insertion point to bring the measurement surface up to where the overfill is, but even that is an approximation.

It was an just an estimate and probably estimated on the low side. My searches on how much is two much was coming up with 2 millimeters which is about .078 or 5/64 so needless to say I’m at the dealership having this corrected. But totally agree that it’s difficult to get a precise measurement especially after the oil change the oil was so clear.

 

[EdP]

I've never seen oil expand with heat, maybe it does, but I have personally changed the oil in thousands of cars and never seen it. The reason to not overfill: "When too much oil is added, the level in the oil pan becomes too high. That allows a fast-moving lobed rod called the crankshaft to come into contact with the oil and essentially aerate it. The result is a foamy, frothy substance that cannot properly lubricate the engine." From jdpower.com

.

This is true, but how much space is there? Quarter inch? Two inches?

I'm sure there is clearance, but does anyone know how much? Big difference if it is a quarter inch or two inches.

How much does engine oil expand when heated?

Assuming easy-math 70-250F (21-121C) oil temperature changes, that's 0.0007/C * 100C = 0.07.. or 7%. So, conservatively, 4–7% seems like a reasonable volume increase of fresh engine oil.