How Often to change the Oil

Why not? Are you so thick that you think they pay the same price per litre for a 50 gallon drum of oil as you do for those one litre bottles at a garage?

So Duckhams is crap oil then?

I guess you are.

FOOL.

Really? Riiiiight.

Or to buy oil in bulk.....

Quality of oil. Some of the engine types are no different.

There you are then. Which raises the question of why you said:-

"Take it to National Tyres everytime they run a £10 oil and filter promotion. You can never change oil too many times."

And for your information centrifugal filters have been used in lowly Zetor engines since I can remember and latterly in all Land Rover TD5 engines, which paradoxically have only 12000 mile service intervals. They are also used to clean transmission oils in some applications.

Huw

Huw

No, certainly not.

Your statements lead me to believe that:

a) you've some grounding in metallurgy, or: b) You have read some bumf, and a) does not apply.

I *wonder* which it is. Hm?

Indeed. Some engines still have 4500 to 6000 mile oil change intervals but they are almost obsolete in Western European production except for export to the Third World. The *minimum* standard of oil you should expect to buy today is API SL or API CH4. This is a much better minimum standard than ever before and was drafted specifically for longer drain periods with even a higher base oil standard included compared to previously. ACEA has equivilent standards and manufacturers may have other more specific needs and standards set.

Funnily enough I have a modern direct injection diesel of 4.2 litres which has 4500 mile service intervals. Latterly that has been elongated to 10,000 miles they tell me. Which is just as well because since ULS diesel fuel has been available I have always changed at 10,000 miles using superior oil, synthetic to MB228.5 spec in this case. Clean fuel has a large influence on service intervals and itself has facilitated a large proportion of the increased intervals.

Huw

Conor ( snipped-for-privacy@gmail.com) gurgled happily, sounding much like they were saying :

How often does a Merc Actros get started from cold, driven a mile, then parked up, before being started from cold several hours later, driven a mile, then parked up over night?

Conor ( snipped-for-privacy@gmail.com) gurgled happily, sounding much like they were saying :

And dealers always use the bang-up-to-date recommended oil? What about non-dealers? Or owners, for topping up?

Thing is, virtually all modern cars have brake pad wear sensors (ok, this is hardly a recent development), which is the main thing that could potentially wear out within the 20,000 miles. That and tyres. So as long as the driver is aware of how to do a basic check of a tyre's tread, and is aware of the brake pad warning light and what it means, then as long as the service is done properly (not only service items replaced, but the condition and operation of everything checked, such as brake pipes, brake pad sensors etc.) there shouldn't be any real liability issues. Brake pipes won't go from fine to rotten as f*ck in 20,000 miles - if they're showing signs of being a bit knackered, then it should get advised. Same goes for shocks, suspension bushes etc. Though I do doubt anyone actually properly tests that the brake pad wear sensor is properly working though.

Yes, true, but at the end of the day if they proved to be unreliable using those service intervals, residuals would be lower, lease prices would be higher and fleet managers would steer clear, so maybe there's something in it.

Yet they are still more reliable than ever before. A major factor in any repair and generally more important than the part cost, is the cost of labour. This is now higher in proportion to the cost of replacing a car. Luckily the cost of acceptable old cars is low due to availability so it is not a huge problem. But honestly, your examples above could be said about any period in automotive history. Open drives changed to closed gearboxes. Chain drive axles gave way to live axles with enclosed crown wheel and pinions, rear drive changed to front drive which made changing the clutch much more problematic. Luckily with each advance which made the car more sophisticated and demanded new repair skills, the reliability generally improved [with a few hickups].

Labour costs and the general lack of skilled labour at car dealerships have pushed makers to produce cars where replacement rather than repair is normal. There are ever fewer skilled mechanics and more simple fitters in dealers workshops. This is maybe not a wholey 'bad thing' as it may be the most efficient way to work.

Huw

There's an interesting claim made on

I haven't been able to google up any further information to substantiate this claim.

John

Huw (hedydd[nospam]@tiscali.co.uk) gurgled happily, sounding much like they were saying :

What's your local garage use? Or even the main dealer?

AstraVanMan ( snipped-for-privacy@whataloadofforeskinbollocks.co.uk) gurgled happily, sounding much like they were saying :

Mmmm. Pinacle of reliability, aren't they?

Point me to a co. car driver that ever bothers doing anything other than getting in the bloody thing and driving it. Even something as minor as checking the oil or washer fluid levels... Look at the *tyres*?

How many cars pull 38 to 44 tons for a living? Those things last about a million kms between engine rebuilds.

I have a Land Rover which has had exactly that regime since new in 1984. It obviously has not that many miles on it [work it out if you like] but has done over 10,000 actual hours of running. It has the occassional 14 mile round trip, usually towing an average of 3 tons. The engine is extremely hard on its oil, as anyone who has owned an indirect injection LR engine will testify, and it has been changed every 5000 miles from new. It is still running like new, although its 3 litres per 5000 mile oil consumption has increased over the years to around a litre every thousand miles.

Huw

Oils have a minimum standard. Oil for topping up even the longest service interval engine will be to that minimum standard or better which is all that is needed. Dealers and even decent non franchised garages have charts and books of materials needed for servicing different models, including the oil needed. Ultimately it is the owners responsibility to ensure the garage knows what he wants as and in a service. It is easier all round if the service book and official schedule are followed.

Huw

They use Fuchs oil in one and either manufacturers own [that's car marque] brand oil [in a franchised dealer for franchise cars] or Morris oils at another. I don't remember the name of individual oils used but do remember the Fuchs Titan Cargo 10w/40 that I supply for the Toyota and BMW diesel engines.

Huw

Even with the longest service intervals certain things like checking the tyre condition and pressure on at least a weekly basis remains the drivers responsibility. Same thing goes for fluid levels and brake condition, seat belt operation and appropriate use at all times notwithstanding idiot lights which may be fitted for all of these and more. Same goes for assessing icy conditions and obeying the rules of the road. Just because the major services are far apart it does not abdicate the

My wife refuses to read car instruction books. I could bloody strangle her sometimes. All this and more is explained within most instruction books.

Huw

There is a very good reason for this and it is also relevant to air filters. When they are new they are least efficient as filters because the pores are at their most open. Once they start to trap dirt they filter finer particles up until a point where they reach capacity where they restrict the flow unacceptably.

Also there is a chance that dirt is introduced with each oil change. There is also the remote but not unknown possibility of misattached filters and loose or stripped threads on drain plugs.

Huw

I should say that I have not read how to strangle ones wife in a car manual yet. Maybe they should find a way of forcing people to read it. It is not a trivial matter.

Huw