True Miles Unknown (TMU) is the more polite cousin of its far more blunt and plain-spoken relative, Not Actual Miles (NAM). These two terms are used to describe a car that had one of a few different tragic events happen to it.

Often seen in classified advertisements in abbreviated form, TMU and NAM mean exactly what they spell out: that mileage history is a big fat question mark. It could have only 83,000 miles, or it could have 283,000 miles. Your guess is as good as the homework you do. That homework starts with the vehicle history (CarFax, AutoCheck, or publicly available records) but even then, you can be stuck.

What is a vehicle with true miles unknown or not actual miles?

  • In some cases, the original odometer broke and got replaced at some point with one reading different mileage.
  • In others, the odometer is still broken or it only reads out five digits – some vehicle histories will say the true mileage of the vehicle “exceeds mechanical limits.”
  • Sometimes, it can be proved that the odometer was rolled back by a felonious scumbag to show fewer miles.
  • Finally, it’s possible a mileage error got recorded on the back of the title – during vehicle sale or transfer – resulting in a new title that now reads “true miles unknown” or “not actual miles.”

Should I buy a TMU / NAM vehicle?

  • If you do buy a True Miles Unknown car consider the source. At an auction, you’re best off getting it from a bank, government agency, or a non-dealer who doesn’t have any incentive to intentionally disable the odometer reading. I have seen a few big and small dealers tamper with an odometer… and it’s never in your favor.
  • Private sellers are a completely different animal. They are often told their cars are worth next to nothing if it bears a TMU / NAM mark on the title. Many individuals will underprice a true miles unknown vehicle they’re selling online because dealers will routinely make lowball offers on these vehicles when it comes time to trade them in.

Gallery: True Miles Unknown

Where can I buy a TMU / NAM vehicle?

  • Credit unions and banks sometimes carry TMU / NAM vehicles. I purchased a classic Ford Ranger from a credit union that was advertised as having 541,000 miles and “True Miles Unknown” plastered on the windshield. I inspected it and discovered it had only 54,100 miles.
  • Dealers are another source of TMU / NAM cars and trucks. A one-owner Toyota Highlander in nice condition came from a local dealership with marred mileage history, all because the dealer checked the wrong box on the back of an out-of-state title.
  • Government auctions, auto finance companies, and other local entities will often have vehicles with TMU / NAM history. I was able to pick up a 1994 Ford Explorer for $100 from a municipality in metro Atlanta with no keys or title and TMU history. I rectified many of those issues and sold it for $2,000.

What should I be careful of with a TMU / NAM vehicle?

  • Purchasing a TMU / NAM car from a private party can result in an outstanding deal, since as I mentioned, those folks have been told their vehicles are undervalued. However before you buy it, make sure to get a Carfax first and see if you can approximate the miles by estimating the annual mileage accrued before the odometer issue took place. An owner who drove the vehicle about 15,000 miles a year and then had virtually no uptick in the mileage several years afterward probably had a similar number of miles driven during that time. I have landed some amazing deals over the years this way.
  • As with any used car transaction, a reputable pre-purchase inspection can help identify potential problems or deferred maintenance that the mileage reading (or lack thereof) may not reflect.
  • If you choose not to do your due diligence or if you end up with a vehicle that you feel wasn’t accurately represented, prepare for a frustrating legal battle. Most states only cover damages that you can prove, and it’s difficult to prove that a selling dealer intentionally misled you. If you are able to do that, you can pursue “treble” damages that include up to three times what you paid for the vehicle, plus all the other costs associated with the lawsuit. Collecting that money is another difficulty, however.

As a dealer, I love true miles unknown or not actual miles vehicles because I find them incredibly easy to figure out with a Carfax history and an inspection before purchase. Then I explain that history to the customer over the phone and email them a copy of the Carfax history before they come to drive the vehicle. That way they know and understand exactly what I mentioned in the ad about the mileage history. That groundwork makes a big difference when buying a car labeled as True Miles Unknown or Not Actual Miles.

Eliminating uncertainty yields a better bang for your buck. So always take the deeper dive and figure out the odometer history. Also verify its overall condition with a mechanic who has a more experienced set of eyes than your own.

That’s how you replace the question mark that is the mileage reading with the exclamation point of a great deal.

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