Annual car maintenance cost and percentage of Replacement Asset Value of running a car under the decision to service it only once a year

The maintenance costs spent on a 2005 Toyota Corolla Ascent brought new in an experiment to test if one annual maintenance service was sufficient

The maintenance cost as a proportion of Replacement Asset Value (RAV) was determined each year and tabulated during the first nine years of operating life

In December 2005, an experiment was started to measure Car Maintenance Cost as a Percent of the Replacement Asset Value (RAV) of a new car (price at AUD $19,831) ovwe the coming years of operation. After purchasing a new Toyota Corolla Ascent with a 5-speed manual gearbox I decided to have it serviced only once per year, each December, and not twice a year as recommended by the manufacturer.

This decision was undertaken as an experiment to see if lower maintenance service costs were possible without detriment to the car or its use. The car was used in the city of Perth, Western Australia, which has a temperate, Mediterranean climate. It was garaged under cover every night and used for about 10,000 – 12,000 km per year, which is about half the typical distance a car is expected to cover annually. The vehicle was mainly used during business hours to visit clients in the city and occasional site visits to towns a couple of hours drive from Perth.

The table below logs the annual car maintenance cost I paid and shows them as a percent of replacement asset value (RAV). The table has both annualised cost, where the total maintenance costs over the car’s life is averaged across the years, and the annualised cost discounted back to 2005 value presuming a 2.5% annual inflation rate. Comments on the condition and use of the car are included, with further detailed explanations on costs noted under the table where required.

December 2010 Comments and Explanations

The leaking shaft seals in 2010 were unexpected so early in the car’s life. Even the car service staff were surprised, but they told me that it occasionally happened. I was not impressed that these problems, which one should not see during the first ten years of use, were happening so soon with the car. Even teaching my son and daughter to drive should have caused no difficult situations for the rear main oil seal or the drive shaft oil seal.

It would also be difficult to claim that doing an annual service, instead of the six monthly services recommended by the manufacturer, contributed to the failed oil seals. The rear main oil seal failure was during Year 4 and the drive shaft seal failed during Year 5. The failures are so early that it is unlikely missing the six monthly service was the cause of the failures.

For the time being I will keep to the annual service schedule and see what costs arise. The tyres are approaching the time to change them. From the tread depth left the replacement should be in 2011.


December 2011 Comments and Explanations

The two front tyres were replaced with new tyres as they had insufficient tread depth to last another 10,000 km. The minor maintenance items seem to be age related and one could expect more of these minor repairs each year from now on.

With the car being used by three drivers it will be interesting to see what sort of failures and maintenance problems start to increase. More scratches and marks from car parking events are appearing on the outside panels now that the car has three drivers and is being used more often.

The maintenance costs as a proportion of asset replacement value for the year was 2.9% annualised. With the car now six years old it is doubtful the RAV will ever return to the 1 and 2 percent of its youth.

I am still of the opinion that doing an extra service each year would have brought me no more benefit than an annual service. At this point in the car’s life, and noting the problems that have arisen in the last six years, had I done 6-monthly services I would have paid nearly twice as much for car maintenance and got no value from doing the extra service.

The intention is to keep the car for one more year, after which it will be replaced with a new car.


December 2012 Comments and Explanations

The work was actually done on 9 January 2013. It involved a full major service, plus a new drive belt, as the one in use was severely cracked, along with front tyre balancing and alignment due to one-sided tyre wear.

During the year a car parking hit by a SUV bull-bar dented the rear driver side panel. It was not worth getting repaired.

The work done during the service and the cost was what one would expect for a city-driven car of its age and working life. During the past seven years the Corolla has been reliable and trustworthy, though a little more expensive to keep than normal due to the shaft seal problems which should not have occurred.

I have brought a new city car and passed the Corolla to my two kids to share while they complete university.

My intention is to put the new car on the same maintenance strategy as the Corolla—one service a year—as there was no evidence that it was detrimental to service life. To be strictly scientific, there should be thousands of cars put through this test before I can be sure of my claim. With continually improved technology the new car’s manufacturer now recommends servicing every 15,000km instead of 10,000km. That is once a year for this new car.


December 2013 Comments and Explanations

Throughout the year the car was driven about the city, shared roughly equally by its two young drivers.

During the year one of the kids hit a post and damaged the rear, driver-side, passenger door. Fortunately the damage was near the car park dent from last year. Both knocks were fixed by the insurance company. The cost of the insurance excess was $900 and is not included in the annual maintenance table, as it is not a normal car maintenance cost. Inclusion of the panel repair insurance excess would skew the RAV values and be unrepresentative of regular car maintenance costs.

The car is now eight years old and showing effects of its age, like low gas pressure in the air conditioner, shaft boot rubber degrading, and accumulation of build-up on fuel injectors.


February 2015 Comments and Explanations

Around mid 2014 the car was brought by my young adult daughter and driven exclusively by her about the city for work and recreation. She also made two country trips totalling some 2,500km distance. Both trips were on bitumen roads.

As well as the late annual service in February 2015, the clutch was replaced in May 2014 at 111,425km. The clutch pins had worn into the flywheel and was well past its serviceable life. So it was replaced new and the flywheel was skimmed. The late annual service was a 120,000km major service, including front brake pads replaced at 3.5mm thickness and the discs skimmed. The car maintenance during the past 14 months was the most expensive ever, with the RAV for the period over 15%. It is a clear signal that many working parts on the car are wearing out. Those wearing parts not yet replaced will need to be renewed in the not to distant future. The obvious thing to do in the next few months is retire the car and buy a new one before more problems start happenning that require major expenditures.

This entry for Year 9 is the last entry to be made. The Corolla continues to be used by my daughter. Because of the rising annual car maintenance cost I advised her to start saving for a new car.


My best regards to you,

Mike Sondalini
Managing Director
Lifetime Reliability Solutions HQ