Hi, I have a 2005 ES series 11, 3.5 Lt. wagon with 150,000 k ms. It goes through a bit of oil every few weeks, although does not blow any smoke at all. I am using 15W 50 synthetic. Why is it using oil, and am I using the correct oil. Any help would be appreciated.

Cheers.

What oil brand do you use?

Why is it using oil, and am I using the correct oil.

Check your rocker cover gaskets, and front engine seals. If there is no leaks evident, and no fresh leaks evident on the driveway or wherever you park, it'll likely be the valve stem seals. Does it blow smoke?

15w-50 is a good weight so that shouldn't be an issue, have you actually looked under the car to see if the lower half of the motor is covered in oil or whether you are dropping some?

Exactly what do you mean by "goes through a bit of oil every few weeks"? - at your Kms you shouldn't need to top up between oil changes.

Penrite hpr 10-50 is excellent oil. Use 15-50 of you are happier with that weight. You have a problem if you are leaking oil though

Some synthetics tend to evaporate a little. A bit of oil every few weeks is nothing to worry about. Perhaps try going for semi-synthetic.

When you say a bit of oil, is it like 200mL or 1L? If it goes to low level on the dipstick, then something is wrong.

Some synthetics tend to evaporate a little. A bit of oil every few weeks is nothing to worry about. Perhaps try going for semi-synthetic.

When you say a bit of oil, is it like 200mL or 1L? If it goes to low level on the dipstick, then something is wrong.

Synthetics don't evaporate nearly as much as mineral/semi-syn, as they do not suspend nearly as much water. Synthetics tend to give the impression of more consumption because they are less prone to increased volume from contaminants. In essence, fully synthetic oil stays purer throughout it's useful lifespan.

I suspect the OP's issue is leaking stem seals or rocker covers firstly. If this isn't the case then the oil brand might be a consideration. I would say 15w-50 is a little on the heavy side for an engine with only 150k. A 10-40 should suffice.

15w-50 is a good weight so that shouldn't be an issue, have you actually looked under the car to see if the lower half of the motor is covered in oil or whether you are dropping some?

Yes i have looked under the car and it does not look like it is leaking. There are no oil spots where i park the car.

I would say about a litre or two every couple of months.

I would say about a litre or two every couple of months.

That tells us nothing. Are you doing 500km over 2 months or 10,000?

I drive alot and 'every couple of months' i change my oil and it is always pretty much full. I use fully syn everytime. I suggest a fully syn oil and check or get your mechanic to check for leaks.

The oil consumption figures you quote could be due to a number of factors although I'd lay my money on the way the oil and filter is changed when the car is serviced. Many garages will drain the oil, remove the filter, instal new filter and then add oil till it reads full on the dipstick - then it's start the engine, make sure oil isn't spraying everywhere, bonnet down and park it - job over. If they do not check the oil, the true oil level will then below the full mark due to the filter filling with oil. You then check the oil level a month or so after it has been serviced and notice the level is low and add a litre or so.

Mine barely loses any even though I have known leaks. I would say 100ml every 1000 k's