Our cars:
2011 Corolla automatic, 116k miles, 30mpg, liability only insurance, worth $6400
2012 Fit 5-speed, 100k miles, 32mpg, liability only insurance, worth $6200
Both are in excellent mechanical shape and perfectly reliable, but are each over a dozen years old and we've owned them for a decade or more. They have zero rust because we live in the deep south, but they're getting dinged and scratched up. The Corolla's stereo just died.
The Corolla could be replaced with a brand new hybrid for about $24,000 plus tax (I would not consider the non-hybrid because those have a cone-and-belt CVT transmission). The Fit is essentially irreplaceable because there is no longer any affordable subcompact sold in the US market with a manual transmission. So maybe it would be replaced with another Corolla or a much more expensive Prius.
Replacing both today would cost about $60,000 upfront, and then we'd have a much higher cost of ownership due to full-coverage insurance, higher property taxes, and higher depreciation - none of which would be offset by the better fuel economy because we drive each car only a few thousand miles per year.
Yet our car needs are fully solved with our current rides, and will be for the next few years, so why mess up a good thing and pay more money for transportation? Especially why pay more for transportation when we are not yet FIRE and have an outrageously high annual spend of nearly $60k anyway? Ours were some of the last affordable cars made with the combination of timing chains (not belts) and non-CVT transmissions, so they are great candidates to drive forever.
The Question:The question is, should we invest in preventative maintenance so we can get another 10 years or more out of each vehicle? Our currently-10-year old kid could use one of them as their first car, and milking all the life out of these cars could get us over the edge and through the early years of FIRE. In 10 years our 15 year mortgage will be paid off, so that would be the ideal time to replace one or both cars as the teenage kid inherits (and then probably wrecks) one of our 22 or 23 year old machines.
We already change the oil whenever the lights come on, but to make this plan work we'd need to invest more into maintenance and preventative repairs. Here are my thoughts on what it would take to get an assured 12 more years and 150k miles out of
each old car, beyond the usual oil, tires, brakes, filters, etc:
Work to make a car last a quarter century:Timing chains*: $1500
Transmission fluid flush: $250
Clean intake sensors: $30 DIY job
Oxygen sensors: $60 DIY job
Spark plugs and wires: $70 DIY job
High-end batteries in 1.5 years: $200
Serpentine belt and tensioner: $500
Motor mounts: $450
Shocks and struts: $700
Coolant flush: $150
Modernize audio and add backup cams / bluetooth: $300
Optional repairs**: $40 DIY
Lots of touch-up paint to prevent paint failure: $40
Spray-can undercoating to prevent rust: $60
Regular waxing to prevent paint failure: $150
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Est. total: $4500 per car
If I decided my strategy is to keep these cars until they are 25 years old, I would immediately invest in most of these preventative maintenance steps. Doing this stuff now rather than later makes sense, as we are at the halfway point in the cars' intended lives. Things like the belts, plugs, and transmission fluid would last the next 12 years, and investments to protect the paint need to be happening now if there's going to be anything left in the year 2036.
Reasons Not To:1) The total cost of owning a beater might not be that much higher than a new Corolla hybrid or Prius. According to
Edmunds, a brand new 2024 model Corolla hybrid costs $34,662 to own for 5 years, while a 2018 model non-hybrid (as far back as Edmunds estimates) costs $32,943. So it costs only $1,719 more over 5 years ($344 per year) to own this brand new car instead of a six year old version. Maybe this extrapolates to 12 year old cars and I'm saving less than I think by owning the old cars. Maybe this just reflects the used-car bubble that will go away soon. IDK.
2) Our existing cars could become functionally obsolete if for example gasoline prices go way up - e.g. to $8/gallon. In that scenario, the newer cars getting 50mpg could cost less to operate than our beaters getting 30mpg. There are already pickup trucks on the road getting 40mpg, so what's the point of getting 32mpg in the Fit, for example? The flipside to this argument is that any ICE car - even hybrids - could be functionally obsolete in a few years as BEV tech improves and the cost of ownership falls below what it costs to own any ICE vehicle.
3) Depending on inflation, new car prices could go up each year at a faster pace than I'm saving money by driving the old cars one more year. If the Corolla hybrid is a bargain today, it may not be a bargain in the future, and so I should take the bargain today rather than risking it. If next year's model costs $1,500 more than this year's, did I get ahead or fall behind by waiting?
4) If I invest a lot maintaining these older cars, and someone hits me, their insurance payout will not reimburse my thousands of dollars of preventative maintenance. It'll only pay average market value for a very old car. And it wouldn't take much to total the car so I wouldn't get my meticulously-maintained car back from the body shop. Thus my preventative maintenance investment is at risk.
5) As the cars get uglier and rattlier, and as our wealth increases, we may not be able to stand them anymore. If we'll end up selling in 3-4 years anyway, a lot of the preventative maintenance will have been a waste. One car lives in a carport and the other sits in the sun, so protecting the paint may not be possible long-term.
6) Catastrophic failures such as a head gasket blowing, transmission failure, or air conditioning failure are getting more likely as the cars age. I can reduce the odds of some of these things happening through fluid changes, etc. but not all of them. I could maintain the shit out of the cars and still have a catastrophic failure that sends them to the junkyard.
So what do you think? 1) Invest in keeping the cars going another 12 years or
2) continue to do the minimum and put the money in stocks instead, or
3) pay the price to trade up?
* I could go either way on the necessity of timing chain replacement. They don't break down over time like a rubber belt, and many cars go 200k+ miles on the original chain. Maybe this gets replaced in 5-8 years instead of immediately.
**The Fit has some interior and exterior plastic panels that are broken/missing, the Corolla has some minor paint damage and a minor valve cover gasket leak.