Checking Oil Level cold or hot?

[MGV]

I have the same scenario as minke (OP). And the same engine (EA888 ).

Checking my oil cold gives a lower reading on the dipstick than when checking warm, after the recommended ~5 minute wait. Probably around 3ish mm on the dipstick.

Therefore if i was right at the high mark when cold, i would be ~3mm overfilled when warm. That's why i check when warm.

[Amalgam]

I appreciate the technical nature of this thread discussion, but given that the oil level should not exceed the max mark or the min mark, then if the oil level does not exceed these two extrema ( and for safety, let us say not below the mid point ) then does it really matter if the reading is taken hot or cold ?

As a point of reference, when new, my 125TDI came from the factory with the oil at the max mark when I checked it cold. It has now travelled 12500km and the oil level is down 2mm.

[brad]

I appreciate the technical nature of this thread discussion, but given that the oil level should not exceed the max mark or the min mark, then if the oil level does not exceed these two extrema ( and for safety, let us say not below the mid point ) then does it really matter if the reading is taken hot or cold ?

As a point of reference, when new, my 125TDI came from the factory with the oil at the max mark when I checked it cold. It has now travelled 12500km and the oil level is down 2mm.

Couldn't agree more.

As long as you check it the same way all the time it doesn't matter.

[Finance_Analyst]

I just got my GTI back from service this week and they used about 4.9 L. Checked the dipstick and it is on max, but there is oil right to half way up the stick. Anyone else have this??

[brad]

If it's just a smear of oil up the stick then don't worry. If it's solid then they have overfilled.

[Guest001]

I just got my GTI back from service this week and they used about 4.9 L. Checked the dipstick and it is on max, but there is oil right to half way up the stick. Anyone else have this??

Whip it out wipe it and put it back in to get a true reading There is almost always oil up the stick initially

[rory]

Some engines demonstrate higher oil consumption when the oil is at the max marker rather than below it (not below bottom mark of course)
My new Scania Diesel Bus engine in case. My workshop mechanic suggests filling half way up only so as not get into excessive consumption defined range, as measured by amount of oil added per distance operated. Don't think this is written anywhere.

[golfandtiguan]

Here are two pics detailing the levels. Basically, the oil level should be in the 'dipped' area. Top kink is max, lower kink is min. Hashed/chequer plate area is 'comfort zone'......

In a wet sump setup, as is the case for most road vehicles, measuring oil requires a bit of common sense.

If your vehicle has been running, wait a few minutes for some of the oil to drain back to the sump.
If dipstick is in the 'c' region, wait a few more minutes (could still be draining)
If it stays in the 'c' region after about 10 minutes, then sure, top up a bit.
If dipstick is in the 'b' region, sweet.

Nowhere does it say that oil must always be at the 'a' level, just it should not be more than 'a' (hence why it's called the 'max' level)

The car does not need ~5L of oil in at all times, it just needs enough to have some going through the engine, the sump and scavenge pump at all times. The 'c' level indicated is the level of oil required before you risk starving the scavenge pump, meaning loss of oil pressure, which can lead to engine failure.

And remember, if the check oil light comes on, there's a fair chance you need more oil

[Finance_Analyst]

Thanks guys - it was odd that the stick had oil all the way to half way up the stick. The car was serviced at a VW dealer and I read in the manual it takes 4.7L (not sure if that is inclusive of the oil filter). I provided my own oil and they gave back maybe 0.1L in the container so I assume they were close.

Either way, have warranty to fall back on as the dealer did it should something happen......

[Youdotinmymirror]

I've had my MK6 GTI for 6 years and it's got 105K km on the clock. It's my first time that had this check engine oil level warning light on during the ownership. I've done about 6-7K km since last service in June and lately have been doing a bit of driving in rush hour traffic - ?100km.

I've looked up the manual and it says to check the oil dipstick level after a few minutes of turning off the engine. I've done that and it's slightly over the minimum level. The warning light doesn't come up any more after first dipstick check. I've bought the recommended type of engine oil top up of 1L from the local dealership but I was wondering when is the right time to fill it up. It looks like it should be done when it's warm like after checking the dipstick? So that it doesn't get overfilled as it's the level that's going to be at operating temperature? Just couldn't find that information in the manual. Thanks.

[brad]

but I was wondering when is the right time to fill it up. It looks like it should be done when it's warm like after checking the dipstick? So that it doesn't get overfilled as it's the level that's going to be at operating temperature? Just couldn't find that information in the manual. Thanks.

Don't over-think it.
If you put the oil in and the engine is cold then go to the top of the crosshatch section and recheck later when the oil is hot.
If the engine is hot, go to the top mark.
Don't have a heart attack if the oil is a fraction (1-2mm) over the top mark.

[Guest001]

Some engines demonstrate higher oil consumption when the oil is at the max marker rather than below it (not below bottom mark of course)
My new Scania Diesel Bus engine in case. My workshop mechanic suggests filling half way up only so as not get into excessive consumption defined range, as measured by amount of oil added per distance operated. Don't think this is written anywhere.

Never heard of that I drove several Scanias and we had to check oils and water daily. The bosses order was it should be full and very rarely did they need any. All were used daily and had over 500,000km on them and motors had never been touched. One Merc had done 900,000km and not been touched and hardly used any oil either. For all my 61 years of driving have always checked oil before running motor, clean dipstick put it in again and check it. Has always worked for me. In my Cruiser there was enough floating around in a hot motor to make a difference as it held 11 litres

[gazzmo]

I am an old dude so I have always checked the oil level when the engine is cold and vehicle on a level surface, the issue when the engine is warm\hot is how much of the total oil is in the sump, this gives rise to over filling if topped up when warm. This is only my opinion after 43 years of driving and wrenching on my own cars.

[Youdotinmymirror]

Don't over-think it.
If you put the oil in and the engine is cold then go to the top of the crosshatch section and recheck later when the oil is hot.
If the engine is hot, go to the top mark.
Don't have a heart attack if the oil is a fraction (1-2mm) over the top mark.

Thanks for the concise advice. I've had to fill up when engine was warm today as the warning light came up again. I've just poured in 200ml of it and it seems to be sitting at about quater of the middle of the dipstick.

What gazzmo says also makes sense as well. As I have no mechanical knowledge of cars I only assumed that I should stick with the oil level when the engine is at operating temperature as the oil level will rise to that level when running the car - I've read somewhere that the oil level is lower when engine is cold which means it will rise at the operating temperature hence I thought I should use that level to fill. Anyway I guess I'll just get into the habit of checking my dipstick more regularly and fill minimally as required.

[Youdotinmymirror]

Just checked the engine oil level in the morning when cold and it seems to have gone up about 1-2mm than when it was warm yesterday. It is different to what I've read so I guess filling it when cold would be better although shouldn't make a big difference if it's at low and filling it minimally.