Best of Deals Car Reviews Repair Shops Cars A-Z Radio Show

Doing NO preventative maintenance: Which strategy costs less over time?

I’d like to see a study on the cost of maintaining a car vs not doing any maintenance at all.


Do extensive preventative maintenance on car.
Proactively replace parts before they break, etc.
Put in $xx,xxx into car and get 200k miles


Only change oil. Fix stuff as it breaks.
Junk car when tranny dies at 125k.
Put $x,xxx into car.

Over the course of 1 mil miles, I wonder which one is cheaper.
I say the latter. Those “extra” miles are expensive.

Both cases start with new car.
One does minimal repairs and replaces car every 125k miles.
The other does maximum repairs and gets 200k miles before buying new one.
Which strategy costs less over time?

Have you considered the “costs” involved in…
…being late or absent from work
…not being able to get to a hospital ER
…missing important appointments, such as job interviews
…breaking down while passing a bunch of 18 wheelers
…being stranded in a dangerous location…all of which can result from a no-maintenance approach?

There is much more to consider than just actual mechanical repair costs when someone decides to not maintain a vehicle. Or–in other words, someone who has an adult-level sense of responsibility should (hopefully) realize that everyday life is filled with situations that require a totally reliable vehicle, and one that is not maintained would be a potentially UNreliable vehicle.

I completely disagree. You can spend $40,000 to get 125,000 miles or you can spend maybe $42,000 to get 200,000 miles. Clearly the second choice is far cheaper, especially as I’ve ignored the cost of a tow job or two and maybe even an unexpected hotel room in the first scenario.

After a car is paid for and insurance is cut to liability only the cost to drive is drastically cut. Do the math. I have not made a car payment for a personal vehicle since 1974. And I don’t intend to ever make another payment nor do I intend to pay collision or comprehensive insurance. My cost per mile to drive a full size pickup is cheaper than the per mile cost to drive a new Prius. And if I don’t drive it it sits there for free.

You have postulated two extremes, as is in most situations in life, a middle ground makes more sense, modified by your own situation. For example, suppose your transmission fails at 80,000 miles, do you then junk the car?
In my case I live in an area where they carpet bomb the roads with salt in the winter. Ten years here seems to be the point where the structural integrity is affected. Car design seems to play a part, I have seen some cars go to fourteen years but that isn’t something you can predict when you buy the car.
We usually have a newer car for trips and an older minivan for hauling things or people around locally or when the weather gets really bad.
I think most people make the best choice for their own situation. It’s not one size fits all.

Your first case includes doing unnessary work (replace stuff before it breaks), which has been discussed here several times. No need to do that, except as part of maintenance where there labor’s already been done (like replace idlers and the water pump when doing a timing belt).

The real answer is C: Do the maintenance by the book, according to the owners manual. Add to that only some (inexpensive) fluid changes (transmission, brake). Do NO flushes, or extra maintenance pushed by dealers and shops.

You’ll have one car that goes 250k, rather then buying two 125k cars. MUCH cheaper.

Fleet owners and managers do these kinds of studies. There are publications that cater to fleet managers, google some and search around and you can find them.

I don’t do preemptive replacement of parts, with the exception of motors with timing belts. Otherwise I change oil, and other fluids, and fix or replace as needed. I don’t replace parts until they either break or produce symptoms due to wear, such as a noisy or clunky CV joint.

The two scenarios in the OP will need tires and brakes to be road worthy and safe. The 2nd (the latter) skips changes of other fluids and I’ll presume would not do a timing belt job on an interference engine either. What other parts would be “pre-emptively” replaced in the 2nd scenario? Lots of cars go 100K now on the original spark plugs. In scenario #1 I’d replace the plugs once and add in a few air filters. In scenario #2 you’d skip the plugs, but what about air and other filters. Doing maintenance as per mfg recommendations in scenario 1 would add about $1,000 to 1,500 the higher number for a timing belt engine.

If you want to just do oil changes and nothing else and trade every 125K miles that might work for you. I drove a company fleet car for many years and the replacement cycle was 3 years or 55K miles. Basically those cars needed oil changes, brakes, and tires. Some shops tried to sell me struts, and claimed torn CV boots, etc. We had to call the fleet dept. for any repair authorizations and most of these were bogus upsells that got rejected.

If I was driving a fleet car today (last one I had was an '00 Saab 9-3) I’d be comfortable running them up to about 100K miles. At the time the fleet dept turned them over at the 3yr 55K miles point because the values dropped off significantly if you got into 65K and more miles. It was residual value of the car that dropped off more significantly with the higher miles that determined when to trade, not increased costs of repairs. Taking a fleet driver off the road while sitting for repairs and rental costs were also part of the equation and these items increased significantly after 60K miles.

The issue for me is do you plan to keep your new car for 100K miles and then trade it in? Or, keep your new car for 10+ years and over that time rack up 200K+ miles. If you opt to trade in and drive 25K miles a year you’ll get a new car every 4 years and you can likely skimp on maintenance. Oil changes, tires, brakes, some filters and fix what breaks. If you opt for long term ownership of the same car; you do oil changes, tires, brakes, some filters, fluid changes (coolant, brake, transmission, differential(s), timing belts (if applicable to the motor), and fix what breaks. Not that much more money and you don’t have monthly car payments for 5 or more years before you get another car. At this time I have 3 cars and zero monthly car payments. My years of driving 35K miles annually are finished and so are my years of making car payments.

Great replies!

Yes, I was postulating 2 extremes, and this is just a theoretical discussion.
In reality, it’s just a matter of diminished returns,
For example, I think changing all fluids is prob. good cost/benefit.

Replacement after something’s broken should not reduce lifetime of car.
So, the only cost you save is getting towed…and inconvenience (as VDC noted)

I guess what I meant was doing stuff that wasn’t absolutely necessary, but suggested.
eg: Tune up at 60k, etc.

I guess it’s pretty easy to figure:

If you buy new car for 35k, and get 125k miles, that is 28c a mile.
So, will it cost less than 21k (75k * .28) to get to 200k?
I think the answer is pretty clearly yes.

Then there’s a third extreme, practiced by a friend who’s an old gearhead/machinist, but is the cheapesr person I know. He’ll buy a used Saturn (he likes that they have timing chains, not timing belts that must be replaced) for $1000, do essentially zero maintenance on it, or the bare minimum to keep it driveable, and get another 100k miles out of it for practically nothing. I haven’t done the math, but for total $ per mile driven ( cost of vehicle plus maintenance divided by miles) he’s got to be a world champion, or pretty close to it.

Not my preferred strategy, but it seems to work for him.

jesmed, I think that strategy, for the average person, would be terrible. First, you can only find junk for $1000. And that $1000 car might need dozens of $500 repairs to keep it going for another 100k.

The best part about that above is that he’s buying an “off brand” car that no one wants. Try that with a Honda. Heck, for $1000, you’ll only get a Honda with a blown motor.

Like I said, not my preferred strategy, but it works for him.

And apparently you CAN find $1000 cars that are not junk, because he does. Just have to know what to look for.

Most of my preventive maintenance consists of fluid/filter changes and keeping them topped off, repack wheel bearings, spark plug replacement every 100-125K miles, serpentine belt about every 10 years or when it shows signs of deterioration, timing belt/water pump at 100K mile interval, radiator/heater hoses/thermostat about every 10 years or when they show signs of deterioration, and parts that are clearly on their way out, or if the part has a lifetime warranty and I’m already doing other work which involves removing that part or is simple removal while I’m there I might do a replacement instead of tearing into it again at a later time. This has worked pretty good for me. In 24 years and 518,700 miles in my '88 Escort I can remember 5 times it’s been towed home. One time was because a wheel bearing went out, one time the fuel pump went out, once the bearing in the water pump seized and stripped teeth off the timing belt about 5K miles before my change interval, one time the timing belt must have just been defective, because it hadn’t been on long, yet stripped teeth from the belt with no other obvious problem (luckily I have a non interference engine) and one time the plastic tank on the radiator cracked and lost the coolant.

I really don’t want to get into theoretical discussions on this anymore since there are so many factors involved. Clearly, in Minnesota, cost is not the only or most important factor in transportation. When its 10 below out, or you have your family in the car, or you have deadlines or are short on time, dependability and comfort are as important. In my million miles, I think I can show it is cheapest to buy new and maintain well, replacing parts as they are needed. For dependability, replacing parts such as alternators, water pumps, belts, hoses, etc. before they breathe their last has worked for me. If you like breaking down on the road, wait for things to break. If you need to make sure you get from point A to point B, do preventive repairs and maintenance.

When adding up the numbers you should also take into account the money expended on car payment interest in regards to the neglect and trade scenario; and that’s assuming a car does not go belly-up due to neglect in 125k miles and leave someone with a worthless trade.

Personally, I don’t like tooling around and worrying if I’m going to get from here to there without having to hitchike part of the way so my methodogy is regular maintenance.

The original post makes a good argument in favor of always buying a brand new car, never a used one. I have heard of this kind of thinking previously. One of my work friends told me that his brother did not believe in changing engine oil and filters. He would run a new car to around 65,000 miles, adding oil when needed, and would trade the car in for a new one.

In my younger years, I used to buy a very cheap car (sub-$1,000/range), put minimal to no maintenance into it, and drive it until it needed a repair that impacted basic functionality or safety. This strategy generally allowed me to get 2 or 3 years out of the vehicle, until something major finally happened.

This system really only worked when:

  1. Automobile was a secondary means of transportation (I lived in a city).
  2. Had a high tolerance for “embarrassing” features (windows not working, smoke out the tailpipe, terrible idle, games to keep it from stalling out or to shift, etc.).
  3. Lived in a city without a emission checks.

The system worked fairly well and a Cutlass Supreme, LeBaron, Omni, and a Skylark got me through the 80’s and a good chunk of the 90’s.


I used that strategy for most of my driving life. I have never, ever had a car loan and I’ve never driven a beater either (by most people’s standards anyway). Everything worked and they looked good. I only recall one breakdown in all those years, it was an alternator that melted down on a Chevy truck. Sure, I had to fix things along the way but that is to be expected. Doing any necessary work myself certainly made the approach possible. Most of my cars were in the $5000 range but I had a few gems like the $800 Grand Am I drove for >5 years before the quad 4 suffered a head gasket failure and I decided not to fix it. That car had 325k miles on the original clutch. Never put a dime into it other than gas and oil changes. Didn’t burn a drop of oil and looked like a gem up until I got rid of it. As long as you don’t feel the need to keep up with the Jones’ and you can do any repair work yourself, that approach works quite well IMO.

If you buy new car for 35k, and get 125k miles, that is 28c a mile. So, will it cost less than 21k (75k * .28) to get to 200k? I think the answer is pretty clearly yes.

You’re forgetting about the price of the new car you have to buy to replace the car that died prematurely because you refused to maintain it. So you need to add $35,000 to the bottom line of not maintaining it.

Or if you prefer, you can assume 20k miles per year (which is quite a lot), and realize that you are getting 3.5 years less out of the car than you should be getting, which means that over your average driving lifetime of 60 years, you will buy 10 new cars as opposed to 6, which will cost you (assuming inflation doesn’t happen, which is silly) $140,000 extra dollars. Factor in inflation and you could buy a house for what you’re costing yourself by not maintaining your cars. And that’s assuming you get lucky and have to stop driving when you’re 80. If you keep driving past 80, it’s gonna cost you an extra 35 grand every 6 years. It’s also assuming that your numbers are correct - a properly-maintained car can go well beyond 200,000 these days, and if you skip the wrong maintenance, your car might die at 100,000.

Depends on the make.

My wife took the do nothing approach except oil at quickie lubes and air filter herself on a new 96 Civic($13.5k) sold in 2005($3k) with 180k. Its only major maintenance was her father taking it and changing out plugs/wires/timing belt/water at 100k.

It really depends on what fails first. Preventative maintenance is making sure avoidable failures are not a factor.