Service intervals (NC).

[rattyntoad]

I believe that Mazda Australia changed the service intervals for the MX-5 from 6 months/10,000km to 12 months/10,000km this year.

This is no doubt a good thing, as a lot of people don't do a lot of km's, so they only need an annual service instead of 2 a year.

But why is it that the service intervals in the UK are 12 months/20,000km???
I would have thought the weather in the UK is just as extreme as AUS ( cold winters v's hot summers), so I don't see that as a reason.

I am particularly interested as I have discounted a 2007 NC with 25,000km, which has only been serviced 3 times - so obviously it has gone over 12 months but not over 20,000km between services. Maybe I should reconsider this car?

[JBT]

The Mazda service interval at every 6 months for late model cars is overkill IMO.

I'd really only be concerned that the hydraulic fluid has been regularly flushed - should be done every 2 years under normal conditions. The NC coolant is good for 10 years and any half decent synthetic engine oil would have been adequate if the oil has been changed 3 times in 27,000 km. Some cars (e.g. BMW only stipulate every 25,000 km - no time) can go much longer provided a good quality synthetic oil is used.

I very recently bought a 2009 Mazda6 with 83,000 km which has, according to its service record, been serviced pretty much on time by Mazda dealers. The last service was in October at 77,000 km but they missed the obvious - like two stuffed engine mounts (also missed on the roadworthy inspection), so go figure.

[Mr Morlock]

25K and serviced 3 times - it should not make a scrap of difference. If someone is doing 6K PA and changing oil every 12 months does anyone really think it going to be a problem? 25K is nothing- the engine may well tick over 200-250K at some stage.

[taminga16]

My motorcycles can sit for a time and the only difficulty that I have is tired fuel, if your use is infrequent it would be prudent to investigate a fuel conditioner.
Greg.

[rattyntoad]

Bear in mind first service was at 1,000km, since then 2 services in 6 years, with 2.75 years/14,500km between service 2 and 3.

I am a little concerned about what this may have done to the engine that manifests itself further down the track (I intend keeping the car for 5+ years).

Anyway, will chase up the seller & see if he has detailed invoiced for the services so I can see if synthetic oil has been used & if any other fluids have been changed.

[davekmoore]

New Mazda 3 with Skyactiv motor etc has gone to 12 months/10,000 kms (whichever comes the sooner). Other Skyactiv (Mazda 6, CX5) models are expected to retrospectively have the same interval from mid 2014. Future new Skyactiv models will have the longer interval.

[Mr Morlock]

My bet is that Mazda does not specify synthetic at least for NC.. Check it.If a mechanic is not instructed to use syn oil then they use their product. Service records do not always define what is done sometimes just a stamp and sig. Plenty of cars are serviced infrequently or when owners remember or can afford and many used cars have no service records at all. Talk to Mazda service dept. The car may have done only about 4k per year- the service should record km related to dt.

[Charlie Brown]

At the very least I'd do an oil and filter change every 12 months and brake fluid every 24 months in these low kilometre NC's, mine's not.

At a Club tech night at Nulon Oils the owner said full synthetic oil starts to lose its protection properties from around 5,000 kilometres being down to 90% protection compared to new oil at around 10,000 kilometres. Mineral and semi synthetic drops to around 50%.

He did mention that the car manufacturers were the biggest winners with reduced oil changes as replacement parts is where they made their biggest profit.

It's cheap protection for your engine to pay $80 for synthetic oil and a $15 filter once a year

[Mr Morlock]

Ever the sceptic- an oil co wanting to flog their product would like to shift users to more expensive oils. Car cos are giving warranties of 100,000Klms and engineers ere on the conservative side- what does the manual say- if engines fail they may well pay. People run std brand oils and clock up 200K+ without hassles. Most drivers are not flogging their cars - exclude track cars - and the key is said to be regular changes. If people want to run syns oils they can but that is not what most service shops are doing without instruction from a customer. People still want value for money whether its oil or petrol and vehicle running on 98 always gets bagged by testers. Running synthetic is something most people would do without really having any data to show it makes any difference but I fully agree that if folks feel more comfortable with that then do it- as CB says its not going to break the bank.

[davekmoore]

Our service manager reckons one service per year with fully synthetic oil is enough on a low annual kms car.

[PeterB]

I have been told that NCs are more sensitive to delayed oil changes as they use a different big end bearing design with no locating tab and can easily spin a big end if oil is not kept is good condition.

I have seen an engine being done at around 100K, so regular oil changes are cheap insurance, particularly if not dríven regularly.

[minipete]

Oil doesn't deteriorate when it sits around unused. It's the number of heat cycles that can cause potential problems.

If a car does lots of short trips (i.e. lots of heat cycles) it can lead to contaminated oil and inferior lubrication. This is what drives the timed service interval.

The tolerances in an engine are correct when it is up to working temperature. When it is cold more fuel can get past the rings which contaminates the oil.

Most MX5's do low kms because of infrequent trips rather than lots of short trips. I would be happy to take the risk and buy a low km MX5.

I would be more wary of a small hatchback with really low kms.

Pete

[project.r.racing]

if you feel unsafe with the new service intervals. you can always do them earlier. i'm sure a mechanic wont mind taking your money.

remember it is now 12 months or 10,000km. most mazdas sold will still do their 10,000km in 5-6 months. it's only the lighter used cars that this new servicing schedule will effect.

one of my cars only does 12,000km per year, and i have always just done the oil change at 10,000km using a full synthetic. so every 9-10 months the oil gets done.

[Mr Morlock]

MX5 are often just leisure cars or "toys". The average KM per vehicle are a crude measure- many MX5s would struggle to do 6000km pa whereas people driving for a living or commuting by daily can be doing much higher KMs. I agree with PRR though- if you want to change the oil more frequently its your call. Dave also should allay concerns with his comments.

[doc]

A lot has been said here already. Me, I am a Mechanic. I have a car that is 37 years old, Just turned 86 thousand miles.
Engine has never been out, Engine has been running Semi-synthetic most of it's life. running full Syn the last few years as I have moved to Australia and the Semi-syn
is Impossible to get here. oil does not, "go off" when sitting. I have changed the oil going by mileage intervals for all these 37 years.
Some times that means every 3 years or so. But I also change the trans and the diff. lubes. Moisture can get into any "Sealed" container. Thus the need to change all the lubes.
I recently bought a NC with but 20 K on it. The previous owner had it serviced at the first service, (approx 1K) and again at about 11K. I remember saying to him when I bought this MY08 car, That it need a service , His take on it was I was nuts! Change the oil every 10K , Way to often. Sorry, I change mine far more frequntly. (By The K's) Not by the years.
Oil does not go off from sitting. But as I said, Moisture is the big enemy.
As per the very low K's MY07. I would have bought it.