TOC Previous Next A+A-Print


Question 145: Must one tell potential buyers that a car’s engine needs to be replaced?

My car is a little over four years old and has sixty thousand miles on it. It never has been in an accident, and I have taken good care of it. So, in many ways it is in excellent shape. But despite regular oil changes and no abuse, when it was in for regular maintenance the mechanic—whom I’ve known for years and am sure I can trust—discovered that the engine is going bad and will need to be replaced. I had hoped to get a few more years out of the car. But now I’ve decided to get rid of it and buy a new one.

I could trade it in on the new car. If I do, I do not think I have to tell the dealership the engine is going bad until the sale is completed. Then I would warn them about the problem so that they could replace the engine before reselling the car. But in the past I always have been able to find buyers for my old cars who would pay more than the dealer would give me. I would like to do that with this car, and if I do, I know I must give honest answers to any questions people ask. But if they don’t ask, must I tell them about the engine? If I don’t, most people will not notice anything wrong, because the symptoms are not yet obvious.


This question calls for application of norms requiring truthfulness and candor; it also requires judgment by the Golden Rule. If the questioner directly sells the car, he or she probably may not sell it for more than its market value, and should carefully estimate how much that is. In making a sale, lying always is excluded, fairness always is required, and neighborliness should not be neglected. The questioner’s responsibilities will depend partly on local practices regarding such transactions and partly on his or her own financial condition and that of potential buyers. Christian mercy may require the questioner, especially if he or she is prosperous, to be more candid than most upright people would be and to sell the car for less than its estimated value.

The reply could be along the following lines:

There is a possibility you do not mention: to sell the car on an auction lot where buyers and sellers meet, if at all, only after vehicles are sold. I suppose customs and expectations differ at various auto auctions, but at least some, conducted with the understanding that sellers give no assurances, are frequented by sophisticated buyers, who examine beforehand the vehicles in which they are interested. I see no moral problem in offering a car such as yours for sale on an auction lot like that.

I also agree with you that, if you trade your car in, you need not tell the dealer about its engine until the transaction is completed. Considering why that is so will throw some light on the conditions under which it might be fair for you to sell the car directly to a private buyer.

To begin with, it is not likely that you could take advantage of the automobile dealer even if you wished to. Dealers generally are knowledgeable about the market value of cars, and before making an offer they can obtain the expert advice of their own mechanics in assessing the condition of a car offered as a trade-in. Then too, paying wholesale prices for parts and labor, the dealer could replace the engine at minimal cost and market your car, otherwise in excellent shape, at a premium price. Moreover, since the dealer’s offer for any trade-in leaves a margin for occasional errors of judgment, any offer you accept will be low enough to help ensure that the dealer’s losses on some transactions, including that one, will be offset by its profits on others. Considering all these things, I agree with you that, if you traded in your old car, the dealer could not reasonably expect you to volunteer what you know about its engine. Provided you told no lies and did nothing to conceal the engine problem, trading in the car would not be unfair to the dealer.

By contrast, if you sell it directly, you probably will be passing your problem on to someone no better able to deal with it than you are. The buyer might well be unable to assess the car’s value accurately; in replacing the engine, he or she probably would pay retail prices for parts and labor; and someone who suffered a loss by buying your car could not write it off as an expected expense. Therefore, it generally would be unfair for you to sell your old car directly for more than its market value (see LCL, 832–33). To see the point, you need only apply the Golden Rule by putting yourself in a buyer’s place.

But how do you estimate the market value? Begin by determining as well as you can the current price in private sales of typical, similarly equipped vehicles of that make, model, and year. Subtract from that the probable cost of replacing the engine, including a reasonable allowance for temporary loss of service. Finally, adjust that price upward, taking into account the car’s excellent general condition and the fact that the new engine will run longer than a typical engine in a car like yours would. These calculations should result in a reasonable estimate, from which other reasonable estimates would differ within a rather narrow range.

How should you go about making the sale? This question calls for more than one answer, depending both on local practices regarding such transactions and on your own financial condition.

Suppose people selling and buying used cars where you live generally bargain aggressively: sellers ask more than they think their cars are worth, claim they have received other offers, exaggerate their cars’ good qualities, evade disclosure of defects (and perhaps even lie about these matters); buyers offer less than they think a car is worth, claim better deals are available, and affect disdain for the car. Suppose, too, that you are not well off and need to get all that you fairly can for your car. If this is your situation, you may proceed as people usually do except in three respects. First, you may not lie—though initially asking more than you think your car is worth and speaking of it with the usual puffery will not be lying.347 Second, you may not in the end accept more for the car than you judge fair—though you might rightly judge it fair to accept more than your estimate of the car’s market value from someone clearly more prosperous than you are. Third, you may not unfairly sell the car to certain persons even for what you estimated to be its market value—for example, to an unsophisticated person who could not afford to replace the engine and would be likely to suffer grave harm if he or she bought your car, even at a price reflecting its true value.

If practices where you live are as I have described but you are well off, so that you can risk getting somewhat less for your car than it is worth, you should proceed differently. The usual practices are a social structure distorted by sin. They occasion sins in violation of the three respects, just mentioned, in which an upright person should depart from them. They impede neighborliness and generally result in transactions in which true cooperation is absent or minimal. All too often, such practices also lead to serious injustices against the vulnerable. You should exercise Christian mercy by opposing these evils. You might do that in various ways. One way would be to offer your car for sale at what you estimate to be its market value, fully explain how you reached that price to anyone interested in buying, refuse to bargain significantly and explain why, take the risk that some potential buyers will be put off and go away, and accept less than your estimated value from—or even offer a discount to—someone who genuinely needs the car but cannot afford it at that price.

To the extent that local practices are less distorted by sin, such a way of acting on the part of prosperous sellers would be less a matter of mercy and more a requirement of fairness and neighborliness. But if you are not well off and need to get all you fairly can for your car, you need not take the risk of putting off potential buyers by disclosing the engine’s condition. Moreover, you could rightly ask initially slightly more for the car than its estimated value and accept that full price from a prosperous buyer, though not from others. Still, you must not lie to anyone, and puffery would be lying. Then too, if a potential buyer’s comments and questions make it clear that he or she wants or needs the information you do not initially volunteer, you should be straightforward, not evasive. Moreover, if you suspect that someone about to buy the car for what you estimate to be its market value would experience serious hardship in replacing the engine, you should frankly explain the problem in order to avoid taking unfair advantage of him or her.

347. Puffery refers to exaggerated commendation of someone or something for promotional purposes. Using it is not lying in a situation where such exaggerations are common enough that one can reasonably expect the hearer not to misunderstand them as factual claims that would be false. But like other exaggeration, puffery is lying in a situation where it expresses false claims, which are likely to deceive hearers.