My Half Price Ride - Maintenance

Everything I needed to know, I learned from my grandparents. Two of my grandma’s favorite sayings are “A Stitch in Time Saves Nine” and “An Ounce of Prevention is Worth a Pound of Cure”.

She’s right. Preventative maintenance is the best way to avoid costly repairs. When talking about vehicles, the most affordable car is reliable, has good fuel economy, and you own it for a long time. You will pay less in repairs and depreciation.

Another Grandparent Lesson: “Knowledge is power”

Before 2023, I did not know much about cars. I did not know how an engine worked. I read that changing your oil regularly was important, but I could not explain why. I followed the instructions in my car’s Owner Manual. I would take my car to a mechanic for every single rattle & squeak, to prevent my old van from breaking down.

I changed my lifestyle in 2022, drastically reduced my annual expenses, and replaced my 2007 Toyota Sienna minivan with a 2018 Toyota Prius Prime plug-in hybrid. I took steps to reduce the cost of operating it.

I decided to learn about car design, operation, and maintenance.

I took a crash course in vehicle construction and repair. I wanted to learn how to keep my car for a long time, at an affordable price. I like knowing how something works, saving money, and making wise choices, so I was motivated.

I learned about 4 kinds of car knowledge: how do cars work, how to maintain them, how much does maintenance cost, and how to do major repairs. I focused on the first 3.

How to Maintain Cars

Maintaining a car requires knowledge, starting with the basics. I highly recommend everyone learn to do basic car maintenance. I split this knowledge into ‘levels’. The first 3 levels require minimal time/expertise, have a low level of risk, and will prevent a lot of headaches.

Do It Yourself (DIY)

Here is the maintenance I did on my car, and why…

Maintenance, Baby!

How to make a car last 300,000 miles: maintenance, maintenance, maintenance.

My goal is to get my car to 300K miles without major repairs. My gut says this is likely the most cost-effective way to own a vehicle, but I need to look at depreciation rates and repair costs over time to check.

The Critical One - Oil Changes

Oil changes are the single most important maintenance item for your car. They are not too expensive, and easy to do yourself. Do them on time. There is no harm in changing your oil a bit early.

Use good-quality oil, and make sure it is the weight (viscosity) for your engine. You can find the recommended oil weight on a sticker under the hood, and on the oil fill cap. Change your engine oil filter each time.

At home, my oil changes cost $16 in materials. My first DIY oil change took 3 hours because I was very cautious. Now they are routine; I can do mine in 45 minutes in my garage.

If I always DIY my oil changes ($16 each), I would spend $320 to do 100,000 miles worth of oil changes. Oil changes are cheap compared to the cost of a moderate-to-major engine repair. It is cheap insurance.

Preventative Maintenance Intervals

When I interviewed mechanics, I repeatedly heard the same advice: Look at the car maintenance guide, and cut the intervals in half, especially for fluid maintenance (oil changes, coolant changes, transmission flushes). For example, I do oil changes every 5000 miles instead of every 10,000 miles.

The reason the official Owners’ Guide is wrong is simple: the Principal-Agent Problem. Car companies make more money if your car lasts for the car warranty, and then eventually breaks down so you buy another car. You save the most money when your existing car lasts a long, long time. You and your car manufacturer have conflicting interests. A car company does not recommend the lowest-cost way to own a car because it is bad for business.

Prius Prime Maintenance Guide

There was too much information, so I wrote everything down into a maintenance guide, based on both mileage and time.

This checklist is the result of hundreds of hours of research into how to maintain a vehicle for long-term reliability. It is based on several sources, especially The Car Care Nut guides, my car manuals’ recommended service schedule, the complete Toyota repair guide for my car, discussions with experienced mechanics, and Prius online forums.

Anything that says ‘check’ means ‘inspect and do repairs if I find anything wrong’.

Monthly, Free

Every 5K Miles or 6 Months, Whichever is Sooner

Every 15K Miles or Once a Year, Whichever is Sooner

Less Frequently

As Needed, Wear Items

How Much Does Maintenance Cost

I have spent $2219 on maintenance in the first 30 months of owning my car, from early 2023 through mid-2025. This was more than I anticipated. That is partly because I had one-off expenses (tools), and because I am doing a high rate of preventative maintenance.

One-Time Expenses

I am hoping these will last me 5 years, so meaning these cost $100/year.

Oil Changes

I spent $445 on 8 oil changes.

Intermittent Maintenance & Repair

I have spent $1104 on intermittent maintenance and repair. These are items that last over a year between repairs.

Ongoing Expenses

Finally, I have spent $173 on ongoing / consumable expenses.

Projected Annual Repair Expenses

Here is the breakdown of my annual maintenance costs per year, including infrequent items.

Less than Annual, Partial Costs

TOTAL: $1139 a year.

Hopefully this will keep my car running smoothly for a long time.

DIY vs Professional Maintenance

I was curious about which maintenance items would save a significant amount of money if done myself, compared with being done professionally. Here is an example - the DIY vs Professional costs for the maintenance of a 2018 Toyota Camry over 100K miles / 8 years.

Doing all repairs professionally would cost $9740. Doing all repairs DIY would cost $2945.

A few items (replacing filters, windshield wipers, batteries) are slower to do professionally and more expensive. Those are obvious things to do yourself.

Other items are significantly cheaper to DIY and require a modest amount of time: oil changes, replacing brakes, spark plugs, transmission fluid change, coolant changes.

Like so much else about owning a vehicle, the key is making informed choices. To do car maintenance correctly, you need to know a bit about how cars work….

Published 15 November 2024