Phenomenal oil consumption--the good kind

[Jameel]

I'd be curious to see how much oil others' cars are using. Post and boast your best consumption rate.

I'll go first.

I have a new engine that's using around a quart every 4k. But that's not the car I'm writing about. My brother's car is a 1979 SC that, to our knowledge, has never been opened. It runs great and the idle drops noticeably when the oil filler cap is off. It has good leakdown and compression numbers for its age and mileage, 95k miles. We bought the car last fall and he's driven it 3600 miles since we did its first oil change this spring. We've checked the oil about every 500 miles and for the first time today since the first change we added 2/3 quart to bring the level back to dead center between the dots. Doing a little math, and assuming the consumption stays steady, it's using about 1 quart every 4700 miles. That just seems impossibly good. We've been religious about checking it, and keep every check logged in a book, so unless there's a German leprechaun topping off the oil tank, we can't explain it. We're using VR-1 20W-50.

[groovydude]

I bought my '82 about 2 years ago, with a rebuild around 12K miles back (new rings and valve guides in addition to seals). I ran my first 3000 miles and the level had barely moved on the dipstick. I know, I'm not driving enough! It's mostly a summer car for me. I just changed the oil to Swepco.

[cassisrot]

PO rebuilt engine at 50k, it's at 115k now and with 3K B-P oil changes I never add oil. It's an 87 3.2 and I do a fair amount of 70+ country road cruising.

[sky1jord]

Bought my '88 in 1992 with 43K on it. Now it has 120K, engine has never been touched, and over that time it consistently uses 1 qt/1500 miles, gets regular changes at 3K miles. I don't know whether or not that's phenomenal, but it sure doesn't bother me.

[Drisump]

As you were saying it seems keeping the oil level at half of dipstick or less, means that you can expect far less consumption compared to a guy that constantly tops up to the high line. Both my air cooled cars (an 85@ 105k and a 96@ 86k) get between 2000-2500 miles to a quart. I suspect that on long cruising runs the consumption is negligible but driving them as I do .....with a certain amount of "elan", I am very happy with these numbers. Cheers

[Nick Triesch]

My 85 911 has never been
Opened has clean
Plugs at tuneup and drives and starts just fine. I get about 600 miles to a quart at 155000 miles on the clock.

[Crude Rudy]

Jameel,

Does your brother drive the SC hard and fast up to redline regularly like a 911 should be driven? Or does he baby it like a garage Queen?

Makes a big difference.

My '84 Cab will use 1/2 a Qt in 300 miles of hard fast driving in one day in the mountains or 1/2 Qt in 2000 miles if I drive her gently. I have ~150K and I dont think it has been opened up, but not sure.

[Trakrat]

I have a 87 that currently has 109,xxx miles on it. Doesn't burn a drop of oil.
No rebuilds that I am aware of.. (based on history of receipts that came with the car).
No oil leaks that I have seen since owning the car and driving it.

I've measure the dipstick in the past 1000 miles and nothing has changed.... and this is with VERY spirited driving.

[Peter M]

How does an engine not burn "a drop of oil"?

It can't, if it gets operated, its an engineering reality that it will. Even the presence of high temperatures will see a small proportion evaporate. Remember the NOACK oil test?

Why doesn't the oil level drop in my car even though I drive it?

The volume of oil loss is replenished by fuel dilution. Often caused by a leaky injector or the accelerator pump or excess choke use on carburettor engines.

The volume of oil is replenished by moisture accumulated through many very short trips.

Reading errors in using the dipstick is also very common.


Ultimately threads like this are just a bit of fun and you need to take in consideration the validity of some of the information presented as factual data.

Carry on!

[Nick Triesch]

Wow! Old 911's that use no oil! Well i' m just going to
Go and say.....impossible! Maybe a Toyota Camry can use very little oil but not an old air cooled 911.

[Dumont]

Just for reference, a before and after shot of the garage queen (2 weeks of no wash and some gravel roads). Redline is the part on the tach where you should keep the needle all the time, right?

[mgar88]

~150k mile car, never opened and driven like a stole it 80% of the time.

The comment re keeping the oil below half on the dipstick is scripture. My car burns through the top half the dipstick but maintains the bottom quarter seemingly indefinitely.

PS- the above car, black on tan with the bright trim, absolutely gorgeous.