Oil level dropped after spirited drive

I check the engine oil level on the dipstick most weekends. I recently did an oil change, the the level was 1 or 2 mm above the max mark (yes I know, it shouldn't have been over the max at all, but I really didn't think this amount of overfill would make a difference, especially to an NA). All was fine, and the level didn't budge at all after 3-4 weeks of fairly sedate driving (which is normal for me).

Then I did a motorway trip at faster speeds than I usually do, doing around 90 leps (not from cold though, I always let the car warm up with sedate driving before going above 3000rpm!). I checked the oil level 2 days after the trip, and it was halfway between the min and max mark.

I checked again the day after (following some more sedate driving), and it hasn't moved.

Does anyone else find that spirited driving causes the oil level to drop? Is this normal?

What I'm most concerned about is, is this a symptom of an underlying problem with the health of my engine?

Thanks

Is the car smoking at all? I would have thought there was maybe an airlock after the oil change, but it does sound like you have lost an awful lot.....

I take it there is none in the undertray or on your drive etc?

H.

Thanks Harvard,

I've had a brief look at the undertray, and couldn't see any oil. I could see a very small puddle of something (it was a wet day), but dipping a rag in it confirmed it was just water. I've also felt around the oil filter to ensure it was on tight enough and didn't leak. I haven't checked the sump plug for leaks yet, but I'd be surprised if there were any.

There's no tell-tale oil on the garage floor, and I've never seen any blue smoke out the back of the exhaust (whether engine is cold or warm).

Hmm. Hope it's not the same as Tricky-Ricky's problems. ie higher speed = higher oil pressure = blowin' oil out the crank seal..Crossin' fingers for you bud.

Were you parked on a slope when you checked the oil level either of those times and did you check on both occasions with the oil hot or cold?

The car was parked on relatively flat ground (flat and level to the eye, but possibly with a very slight slope on it). I always check when the oil and engine are both stone-cold. I usually leave the car for 3-4 hours before checking the oil, to make sure it's all descended into the sump.

Hmm. Hope it's not the same as Tricky-Ricky's problems. ie higher speed = higher oil pressure = blowin' oil out the crank seal..Crossin' fingers for you bud.

Andy: thanks for the tip-off. Do you have a link to Tricky-Ricky's problem handy? If not I'll just PM him. Sounds like something I should look into. I take it from your tone that it's a serious problem?

engine oil will absord water if the car is driven around in a "sedate" manor as the oil temp does not get hot enouth to evaporate the moisure. So when you checked the levels it all seemed fine. .Then when you went for a motorway cruise the temps caused the moisure in the oi to evaporate and therefor reduce the levels on your dip stick.

Top up all is fine

Andy: thanks for the tip-off. Do you have a link to Tricky-Ricky's problem handy? If not I'll just PM him. Sounds like something I should look into. I take it from your tone that it's a serious problem?

He posted today mate. Thread called oh dear...3

Hoping it's what ard said though.

engine oil will absord water if the car is driven around in a "sedate" manor as the oil temp does not get hot enouth to evaporate the moisure. So when you checked the levels it all seemed fine. .Then when you went for a motorway cruise the temps caused the moisure in the oi to evaporate and therefor reduce the levels on your dip stick.

 

Top up all is fine

Sorry mate but oil does not absorb water,in the worst case scenario it will form an emulsion, but this requires a fair bit of water heat and agitation ie head gasket, sedate driving will not cause this, and you certainly would not get enough water in the system to cause the oil levels to rise so you would notice;) think your getting confused with brake fluid.

engine oil will absord water if the car is driven around in a "sedate" manor as the oil temp does not get hot enouth to evaporate the moisure. So when you checked the levels it all seemed fine. .Then when you went for a motorway cruise the temps caused the moisure in the oi to evaporate and therefor reduce the levels on your dip stick.

 

Top up all is fine

He is not wrong. I quote from the Supra owners manual page 94:

Oil consumption: Max 1.0L per 1000KM

When judging the amount of oil consumption, note the oil may become diluted and make it difficult to judge the true level accurately.

As an example, if a vehicle is used for repeated short trips, and consumes a normal amount of oil, the dipstick may not show any drop in the oil level at all, even after 1000KM or more. This is because the oil is gradually becoming diluted with fuel or moisture making it appear that the oil level has not changed.

The diluting ingredients evaporate out when the vehicle is then driven at high speeds, as on an expressway, making it appear that oil is excessively consumed after driving at high speeds.

He is not wrong. I quote from the Supra owners manual page 94:

 

Oil consumption: Max 1.0L per 1000KM

 

When judging the amount of oil consumption, note the oil may become diluted and make it difficult to judge the true level accurately.

 

As an example, if a vehicle is used for repeated short trips, and consumes a normal amount of oil, the dipstick may not show any drop in the oil level at all, even after 1000KM or more. This is because the oil is gradually becoming diluted with fuel or moisture making it appear that the oil level has not changed.

 

The diluting ingredients evaporate out when the vehicle is then driven at high speeds, as on an expressway, making it appear that oil is excessively consumed after driving at high speeds.

Nice. So where'd you get your manual mate? Would like one for J spec.

It came with the car when I bought it. Although mines a UK spec so it must have come with the car when new. I guess the J spec ones had a Japanese owners manual?

Anyway there is an English translation manual here on ebay: http://cgi.ebay.co.uk/93-99-TOYOTA-SUPRA-OWNERS-MANUAL-HANDBOOK-ENGLISH_W0QQitemZ200107590171QQihZ010QQcategoryZ1132QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

It came with the car when I bought it. Although mines a UK spec so it must have come with the car when new. I guess the J spec ones had a Japanese owners manual?

 

Anyway there is an English translation manual here on ebay: http://cgi.ebay.co.uk/93-99-TOYOTA-SUPRA-OWNERS-MANUAL-HANDBOOK-ENGLISH_W0QQitemZ200107590171QQihZ010QQcategoryZ1132QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Yep. Lol trying to read it...

He is not wrong. I quote from the Supra owners manual page 94:

 

Oil consumption: Max 1.0L per 1000KM

 

When judging the amount of oil consumption, note the oil may become diluted and make it difficult to judge the true level accurately.

 

As an example, if a vehicle is used for repeated short trips, and consumes a normal amount of oil, the dipstick may not show any drop in the oil level at all, even after 1000KM or more. This is because the oil is gradually becoming diluted with fuel or moisture making it appear that the oil level has not changed.

 

The diluting ingredients evaporate out when the vehicle is then driven at high speeds, as on an expressway, making it appear that oil is excessively consumed after driving at high speeds.

Sounds like a bit of Toyota customer service bull to cover them from the numpty brigade,

most engines should not gain any significant rise or fall in oil levels due to moisture and fuel contamination, both will cause premature failier!

I have yet to own a car that has done this, bar a fuel system problem,in which case it needs to be looked into! head gasket problem,obvious! or heavy oil consumption due to bore/ring ware,

my Supra uses no oil between changes,(except when blowing the FMS;) ) and docent gain any either:p

and i do a fair bit of short trips.

If it was a sign of engine damage or wear surely they would put. please have your car checked by a toyoto dealer and charge $$$ for the job? Rather then putting its normal behaviour... petrol is a hydrocarbon and would be quite at home in oil if it never got much above 70 degrees. water is heavier then oil and i assume would sit in the sump unless it was churned up or boiled off??

if somone does short journeys or doesnt ever get the oil upto 100+ temps for long i can believe it. Water when under pressure will have a higher boiling point to.

I didn't say it was i sign of engine damage, i said significant volumes of either water or fuel in the oil would result in engine damage, petrol diluted oil is pretty worthless as a lubricant when pressure fed through bearings, the same goes for water, and the water under pressure reference was head gasket related,

my normal oil temp is 100C even on short journeys, normal operating temp is reached quite quickly.

I dont know how long it takes to get the oil up to temp. I've not got a gauge for that. I know it takes a mile or two for the water temp to reach normal and I assume it will take ahwile at the higher temps to boil off the nasty contaminates if theyre there. I guess somone whould have to run the car in pretty extreme circumstanses or over tiny distances to produce those effects in the manual.

Interesting. Still reading with interest....

BTW, my "sedate driving" involves a half-hour journey, most of which is spent between 50 and 70 mph.

I would have thought a half hour drive at those speeds would be more then enough to get well up to temp etc. I think you would need lots of less then 2 mile trips to produce what it says in the manual.

Interesting. Still reading with interest....

 

BTW, my "sedate driving" involves a half-hour journey, most of which is spent between 50 and 70 mph.

do the 'hard' drive again and see if it drops to the 'low' marker..........if not then top up to full and do it again and see if its a down to half............ie keep an eye on it!

BTW do you partially fill your oil filters before fitting? and do you check the level after an oil change, or after a startup and then the 3-4 hrs drain?

do the 'hard' drive again and see if it drops to the 'low' marker..........if not then top up to full and do it again and see if its a down to half............ie keep an eye on it!

 

BTW do you partially fill your oil filters before fitting? and do you check the level after an oil change, or after a startup and then the 3-4 hrs drain?

I'll certainly try the hard drive again Scooter. That should narrow it down.

I don't partially fill my oil filter when I change it. I tend to screw in the new (empty) filter, fill up the dipstick to about the min mark (leaving it for several minutes before re-checking), then run the engine for maybe 20 seconds. Leave the oil to drain for as long as I can (half an hour?), then top it up. I also check it maybe once a day for a few days after the oil change.

I changed the oil several weeks ago, and I try to check it at least once a week. It's these once-a-week checks where I leave the car for 3-4 hours before checking the level. I drive it to work, park on level ground in the car park, and check it at lunchtime.

All this waiting and checking sounds a bit @nal, but I've had some odd readings in the past (on other cars) by not leaving the oil to settle for long enough.

ah ok, i just thought that maybe you weren't doing the filter and then filled to the max.........(this way you'd drop the level next time you checked as the filter would be full/fuller)

but your 20secs and then topup rules out my theory .......

Update: I've been for a couple of shorter "spirited drives" today (with slower speeds, but just as high engine revs), and after allowing the oil level to settle for a few hours, the engine doesn't seem to have lost any oil at all.

So, I think I'll just put it down to a one-off hiccup, and keep an eye on things. Thanks for the help though guys.