Oil filter change in old car - how often?

I recall having one of those transistorised, no contacts ign retrofits on an old car a I had. It had mechanical petrol fuel injection. The difference in starting, idling and acceleration was amazing. I roughly calculated it was

Pour in "pure" synthetic and leave for 36,000 miles. Very cheap and no wear.

Makers have known for 50 years that "pure" synthetics will not wear an engine. They never specified it. They could have had the 100,000 mile oil change engines in the early 1970s, but we never saw them.

Makers design and engine to have minimal Noise Vibration and Harshness (NVH) for 50,000 miles. That can be extended to 200,000 miles easily - an end user can now do that. The only noise will be from water pump and alternator bearings. Which leads to having these lubricated from the engine oil when having 100,000 mile oil change intervals to keep the engine running as new for 10 years minimum.

I recall changing the water pump of a Mini I had. The difference in noise reduction was amazing.

Save money and fill with Millers extended change interval "pure" synthetic oil. Then leave for 30,000 miles with no wear along the way.

The contamination breaks down the lubrication qualities of mineral oil. "Pure" synthetics do not break down, or take an amazingly long time to break down. Read the Popular Science article and the tests Ford did nearly 40 years ago.

It is clear you do not know anything about oil. About 25 years ago I did some work in an oil research lab around Oxfordshire. The Tribologists said "only ever use fully synthetic oils", as the lubrication is vastly superior in every way. Most people thought it was only for "sports" cars, they said "use it in all engines". One stated that in bumper to bumper city driving the water pumps do not run fast enough creating hot spots in the engine. This would bake mineral oil onto surfaces. Anyone who has stripped down a BMC A series engine will have noted the black baked on oil around the cam followers, which needs scraping off.

One guy there would take a sample of oil from his car, it happened to be a SAAB, and test it before any changing of oil. He had gone 60,000 miles on Mobil 1 changing the filter every 6,000 and topping up a little, and it still did not need changing. He said in many cases the filter did not need changing but did it as a precaution. This backs up the Ford tests in the Popular Science article, who in the early 1970s went 100,000 miles with changing the oil. They stated the parts in the engine after strip-down were fit enough to go into new engines

I have used it ever since and prices have dropped like a stone since. Now the water is muddy as to what "fully" synthetic is. One also said it is best to use from new the likes of Mobil 1, when they were "pure" synthetic oils, and use an oil filter with finer filtration. He said the engine will then just last and last with no to negligible wear.

The problem now is knowing what makes of oil are "pure" synthetics. The worst people to ask advice are mechanics, who direct you to mineral oils and keep to what the makers say.

Dave,

you are wasting your time. The bloke is a complete arse writing cr@p all through this thread.

I hope no-one believes him, nor takes him seriously.

regards

David

Oh look! Another k*****ad!

Funny that. When I had a series of Saabs, they always got treated to Saab branded oil. Like gnat's piss.

I think I remember (but maybe this could be memory fade...) that a) it was thinner than Mobil 1 (i.e. it was the right spec. for the motor); b) it was cheaper than Mobil 1; c) it was (to me) more readily available.

Looks like there is a wider range of Mobil 1 products these days.

On the bottle:

API SM CF (for DD)

ACEA C3 (for the rest of us.)

C3 is more for later Euro cars. API specs are better suited for cars across the pond.

David

Tried to buy a Cosworth lately? Or a decent 3 litre Capri?

Chevette HSR, Lotus Carlton.

The value of Pug 205 GTi's is already creeping up.

Perhaps you meant "mass market"?

Strange. 6000 miles intervals in the UK - same as pretty well every other car of the time. Is the 3000 mile thingie in official BL literature - or just the Haynes etc book of generalizations?

Not really. Low use usually equates to short journeys therefore more condensation to contaminate the oil. Certain additives may have a 'shelf life' too - but that's more of a guess.

Which modern vehicles do you mean? Any normal car with a 3000 mile service interval would be a bad joke in Europe. And there aren't that many models exclusive to the US.

So there's no need for a filter, then?

Cleaning the loos?

You'll find black baked on deposits on an engine run exclusively on synthetics from new too - as I discovered when changing the rocker cover gasket on my BMW.

Oh - if you used a modern fully synthetic oil in an A Series engine, you'll experience rapid cam and tappet wear. They don't have the correct additives for this type of engine. Those additives aren't suitable for cat. equipped engines, so inferior types are used.

Didn't take long to get back to normal, then. Go back to your therapist and get your money back.

Large oil companies make much more money having you use cheap petroleum oils and greases and changing them frequently. They make the vast majority of their profits selling petrol, diesel fuels and lubricating oils. The idea of fuel efficient, extended drain synthetic lubricants is counter to their business interests.

Synthetic lubricants and greases are inherently superior products. They would have taken over the market decades ago where it not for the profit motives of oil companies. When I started using Mobil 1 20 years ago and saw how well it was, I thought it would only be a few years before everyone was using the stuff. I went from changing oil every 6000 miles to changing oil once a year, about 12,000 miles, and never looked back. I could have gone to

I was impressed by how well even the early synthetic oils like Mobil 1 performed. Read the link on the 1976 copy of Popular Science magazine in one of my posts.

Synthetic oils are gaining ground and soon will be required for many applications. We are already seeing this with automatic transmission fluids, gear oils and sealed for life wheel bearings using synthetic grease. All the new A/C compressors also use a PAG (poly akyl glycol) based synthetic oil in them. Many use a synthetic power steering fluid. Many makers specify synthetic engine oils, many with semi as mimium, and come this way from the factory. Toyota come to mind. Also some Toyotas had

A fully synthetic oil is available for your '67 truck. Look around and use it. Many older engines greatly benefit from synthetic oils.

That is what the article was hinting at. The Ford guys were reassessing what was help in suspension. Read the article.

You are an idiot.

You will not with "pure" synthetics. As been stated on this thread. There are "pure" synthetics and pretend synthetics.

They do. Read up on API SM oils. They are downwardly compatible. Again "pure" synthetics will cope with tiddly engine like an A series. Millers make a oil specifically for Minis to cope with the gears in the sump.

Exactly. I know k*****ad when I see them. That was a k*****ad alert!

As opposed to very expensive synthetics which don't increase the service time pro-rata.

The long life oil for my BMW is 15 quid a litre. Oil changes approx 15,000 miles at best. A good quality dino oil - with 6000 mile changes - is better value, if nothing else is taken into consideration..

As has been stated by *you* - so not a good start. Look up BMW spec oil. You're good at that.

You've snipped a rather important bit. Here it is again.

'Those additives aren't suitable for cat. equipped engines, so inferior types are used'.

Why would you need a special oil for a few gears in your imaginary world? Many engines already have gears that need lubrication.

You really don't get it. Millers can go to 25,000 miles. The ££s saving clearly points to "pure" synthetics. But that is not the point, he over picture is what matters, not penny pinching.

Raad this US article. It mentions the Popular Science article and the NY taxi cab tests. Concusion of the NY test:

'To summarize the findings and conclusions, the test facility responsible for the demonstration submitted this statement: "The data presented in this report indicates that the Amsoil synthetic SAE 10W-40 passenger-car motor oil formulation.provided protection of the test engines from excessive wear and deposit formation, far beyond the normal 3,000-mile change interval." In fact, the level of protection was such that those engines in which the original synthetic oil was run for the entire duration of the (60,000-mile) test showed less wear than did the Control Group vehicles using premium,

Synthetic show less wear after 60,000 mile than constant mineral oil changes at 3,000 miles.

The article concludes:

'Does all of this mean that synthetic motor oils are superior to conventional petroleum oils? If you value your automobile engine and would like to keep it in peak, trouble-free operating condition year after year and far beyond its normal expected life, our conclusion is "Yes, without question."'