fully synthetic oil

[alanf406]

Hi my first post hooray!

I've been using fully synthetic oil since I bought my 406 about 7 years ago, I usually change it at about 10000 mls but last weekend I was chatting to a mate who has a fairly new seat, he's a rep & does lots of miles but he says there is a sensor on his car that advises when an oil change is due & it is usually about 44000 mls, another mate who used to be a mechanic reckons he's right that they can do up to 50000 but just change the filter at about 10000 mls, what do you fellas think.

alan

[Doggy]

Hi Alan & welcome aboard.

I think most opinion on the site tends toward more frequent oil changes. My personal experience is that with mostly main road / m-way driving my 3 HDi's have all 'told' me to change the oil at around 10k, as they start to get a bit 'tappety' and lose their edge.

What flavour 406 do you have?

[Welly]

A lot of cars have a service 'computer' which record the number of starts, temperatures, distance etc to give 'flexible' servicing according to use.

Without entering a huge oil-change debate, here's my take on things:

Low miles = change once a year.

High Miles = change every 10/12K miles.

Oil has moved on a lot in recent times though and coupled with efficient combustion and oil coolers I can understand how oil can give long service in certain vehicles. Some would say that we generally change our oil too frequently in most cases.

[Bailes1992]

I have a different opinion to Welly.

I think if you are doing low mileage the car isn't going to get upto full temperature quickly and therefore is going to be running inefficiently causing the oil to get dirty quicker. Also if the engine never gets upto operating temperature the oil never gets time to burn off any water that gets into the oil through general combustion.

I change my oil at 6,000miles or 6 months regardless. I have a fairly modern car though and use fully synthetic oils. I do mainly motorway mileage, well I did until 3 weeks ago where I've started working 3 miles from my house.
When I first had my car it was serviced by the dealer I bought it from using Ford Spec oil and a Mann Oil filter. I was going to follow the standard Ford oil change intervals. I took a sample of oil when I had the oil changed at 12,500miles and sent it off to be analyzed. When you get it back you get a list of stuff that's in the oil (that's all gibberish to me), a summary and advice. The basic consensus was the oil was stinking, way past it's best and I should half my intervals.

My Father's F30 320d uses smart intervals where the car works out how often it should have an oil change (I once managed to wipe 4,000miles off the next interval in just 1 hour! ).
It can go anywhere between 12k and 24k without an oil change and upto 2 years!
I know oils have come on a long way but I can't imagine the oil being any good after 24k!

I've come to the conclusion that manufacturers are stretching intervals to make the cars seem appealing to people who want minimum fuss. They're putting reliability to one side and trying to appeal to people who don't want to pay to service their car often. It also makes the car appealing to businesses and people who lease cars. I personally wouldn't want to buy a car that's only been serviced every 2 years. Manufacturers aren't interested if the engine will be knackered at 100k, as long as it gets through the warranty period they are happy.

[Welly]

Manufacturers aren't interested if the engine will be knackered at 100k, as long as it gets through the warranty period they are happy.

I have a different opinion to Bailes.

If, say, in 7 years time everyone was recalling the time when ~~~~"remember those Audi's where the engines blew up after 100K miles?....yeah I aint buying an Audi"~~~~

I think the manufacturers cannot afford any problems so work closely with the oil companies to get the right compromise. Look how Toyota suffered criticism with there accelerator capers, bad press sticks around. Someone in America was recently claiming that fully-syn oil NEVER needs changing and we all change oil far too frequently probably a bit extreme but hey.

And these home oil tests, I'm not sure they're going to report your oil is fine due to a potential drop in sales?

I follow the manufacturers intervals and view these as conservative at the least.

[Bailes1992]

The Ford/PSA 1.6HDi suffers with catastrophic turbo failures and people still buy them!

K-Series gets head gasket failures but people were still buying them!

All manufacturers care about is getting the cars out of the warranty period. People are going to buy brand new cars regardless. In my opinion at least!